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	Author	Živanić, M.; Espona‐Noguera, A.; Verswyvel, H.; Smits, E.; Bogaerts, A.; Lin, A.; Canal, C.
	Title	Injectable Plasma‐Treated Alginate Hydrogel for Oxidative Stress Delivery to Induce Immunogenic Cell Death in Osteosarcoma			Type	A1 Journal Article
	Year	2023	Publication	Advanced Functional Materials	Abbreviated Journal	Adv Funct Materials
	Volume		Issue		Pages
	Keywords	A1 Journal Article; Plasma, laser ablation and surface modeling Antwerp (PLASMANT) ;
	Abstract	Cold atmospheric plasma (CAP) is a source of cell‐damaging oxidant molecules that may be used as low‐cost cancer treatment with minimal side effects. Liquids treated with cold plasma and enriched with oxidants are a modality for non‐invasive treatment of internal tumors with cold plasma via injection. However, liquids are easily diluted with body fluids which impedes high and localized delivery of oxidants to the target. As an alternative, plasma‐treated hydrogels (PTH) emerge as vehicles for the precise delivery of oxidants. This study reports an optimal protocol for the preparation of injectable alginate PTH that ensures the preservation of plasma‐generated oxidants. The generation, storage, and release of oxidants from the PTH are assessed. The efficacy of the alginate PTH in cancer treatment is demonstrated in the context of cancer cell cytotoxicity and immunogenicity–release of danger signals and phagocytosis by immature dendritic cells, up to now unexplored for PTH. These are shown in osteosarcoma, a hard‐to‐treat cancer. The study aims to consolidate PTH as a novel cold plasma treatment modality for non‐invasive or postoperative tumor treatment. The results offer a rationale for further exploration of alginate‐based PTHs as a versatile platform in biomedical engineering.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	001129424500001	Publication Date	2023-12-21
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1616-301X	ISBN		Additional Links	UA library record; WoS full record
	Impact Factor	19	Times cited		Open Access
	Notes	Fonds Wetenschappelijk Onderzoek, 1S67621N ; European Cooperation in Science and Technology, COST Action CA20114 ; Agència de Gestió d'Ajuts Universitaris i de Recerca, SGR2022‐1368 ; Agencia Estatal de Investigación, PID2019‐ 103892RB‐I00/AEI/10.13039/501100011033 ; Instituto de Salud Carlos III, IHRC22/00003 ;			Approved	Most recent IF: 19; 2023 IF: 12.124
	Call Number	PLASMANT @ plasmant @c:irua:202030			Serial	8979
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	Author	Živanić, M.; Espona‐Noguera, A.; Lin, A.; Canal, C.
	Title	Current State of Cold Atmospheric Plasma and Cancer‐Immunity Cycle: Therapeutic Relevance and Overcoming Clinical Limitations Using Hydrogels			Type	A1 Journal article
	Year	2023	Publication	Advanced Science	Abbreviated Journal	Adv Sci
	Volume		Issue		Pages	2205803
	Keywords	A1 Journal article; Engineering sciences. Technology; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
	Abstract	Cold atmospheric plasma (CAP) is a partially ionized gas that gains attention as a well-tolerated cancer treatment that can enhance anti-tumor immune responses, which are important for durable therapeutic effects. This review offers a comprehensive and critical summary on the current understanding of mechanisms in which CAP can assist anti-tumor immunity: induction of immunogenic cell death, oxidative post-translational modifications of the tumor and its microenvironment, epigenetic regulation of aberrant gene expression, and enhancement of immune cell functions. This should provide a rationale for the effective and meaningful clinical implementation of CAP. As discussed here, despite its potential, CAP faces different clinical limitations associated with the current CAP treatment modalities: direct exposure of cancerous cells to plasma, and indirect treatment through injection of plasma-treated liquids in the tumor. To this end, a novel modality is proposed: plasma-treated hydrogels (PTHs) that can not only help overcome some of the clinical limitations but also offer a convenient platform for combining CAP with existing drugs to improve therapeutic responses and contribute to the clinical translation of CAP. Finally, by integrating expertise in biomaterials and plasma medicine, practical considerations and prospective for the development of PTHs are offered.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000918224200001	Publication Date	2023-01-20
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	2198-3844	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	15.1	Times cited		Open Access	OpenAccess
	Notes	European Research Council, 714793 ; Fonds Wetenschappelijk Onderzoek, 12S9221N G044420N ; Ministerio de Economía y Competitividad, PID2019‐103892RB‐I00/AEI/10.13039/501100011033 ;			Approved	Most recent IF: 15.1; 2023 IF: 9.034
	Call Number	PLASMANT @ plasmant @c:irua:193166			Serial	7238
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	Author	Zhou, R.; Zhou, R.; Xian, Y.; Fang, Z.; Lu, X.; Bazaka, K.; Bogaerts, A.; Ostrikov, K.(K.)
	Title	Plasma-enabled catalyst-free conversion of ethanol to hydrogen gas and carbon dots near room temperature			Type	A1 Journal article
	Year	2020	Publication	Chemical Engineering Journal	Abbreviated Journal	Chem Eng J
	Volume	382	Issue	382	Pages	122745
	Keywords	A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
	Abstract	Selective conversion of bio-renewable ethanol under mild conditions especially at room temperature remains a major challenge for sustainable production of hydrogen and valuable carbon-based materials. In this study, adaptive non-thermal plasma is applied to deliver pulsed energy to rapidly and selectively reform ethanol in the absence of a catalyst. Importantly, the carbon atoms in ethanol that would otherwise be released into the environment in the form of CO or CO2 are effectively captured in the form of carbon dots (CDs). Three modes of non-thermal spark plasma discharges, i.e. single spark mode (SSM), multiple spark mode (MSM) and gliding spark mode (GSM), provide additional flexibility in ethanol reforming by controlling the processes of energy transfer and distribution, thereby affecting the flow rate, gas content, and energy consumption in H-2 production. A favourable combination of low temperature (< 40 degrees C), attractive conversion rate (gas flow rate of similar to 120 mL/min), high hydrogen yield (H-2 content > 90%), low energy consumption (similar to 0.96 kWh/m(3) H-2) and the effective generation of photoluminescent CDs (which are applicable for bioimaging or biolabelling) in the MSM indicate that the proposed strategy may offer a new carbon-negative avenue for comprehensive utilization of alcohols and mitigating the increasingly severe energy and environmental issues.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000503381200200	Publication Date	2019-09-07
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1385-8947; 1873-3212	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	15.1	Times cited	20	Open Access
	Notes	; ;			Approved	Most recent IF: 15.1; 2020 IF: 6.216
	Call Number	UA @ admin @ c:irua:165648			Serial	6318
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	Author	Zheng, J.; Zhang, H.; Lv, J.; Zhang, M.; Wan, J.; Gerrits, N.; Wu, A.; Lan, B.; Wang, W.; Wang, S.; Tu, X.; Bogaerts, A.; Li, X.
	Title	Enhanced NH₃Synthesis from Air in a Plasma Tandem-Electrocatalysis System Using Plasma-Engraved N-Doped Defective MoS₂			Type	A1 Journal Article
	Year	2023	Publication	JACS Au	Abbreviated Journal	JACS Au
	Volume	3	Issue	5	Pages	1328-1336
	Keywords	A1 Journal Article; Plasma, laser ablation and surface modeling Antwerp (PLASMANT) ;
	Abstract	We have developed a sustainable method to produce NH3 directly from air using a plasma tandem-electrocatalysis system that operates via the N2−NOx−NH3 pathway. To efficiently reduce NO2− to NH3, we propose a novel electrocatalyst consisting of defective N-doped molybdenum sulfide nanosheets on vertical graphene arrays (N-MoS2/VGs). We used a plasma engraving process to form the metallic 1T phase, N doping, and S vacancies in the electrocatalyst simultaneously. Our system exhibited a remarkable NH3 production rate of 7.3 mg h−1 cm−2 at −0.53 V vs RHE, which is almost 100 times higher than the state-of-the-art electrochemical nitrogen reduction reaction and more than double that of other hybrid systems. Moreover, a low energy consumption of only 2.4 MJ molNH3−1 was achieved in this study. Density functional theory calculations revealed that S vacancies and doped N atoms play a dominant role in the selective reduction of NO2− to NH3. This study opens up new avenues for efficient NH3 production using cascade systems.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000981779300001	Publication Date	2023-05-22
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	2691-3704	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor		Times cited		Open Access	Not_Open_Access
	Notes	ACKNOWLEDGMENTS This work was supported by the National Natural Science Foundation of China (51976191, 5227060056, 52276214) and the National Key Technologies R&D Program of China (2018YFE0117300). N.G. was financially supported through an NWO Rubicon Grant (019.202EN.012). X.T. acknowl- edges the support of the Engineering and Physical Sciences Research Council (EP/X002713/1).			Approved	Most recent IF: NA
	Call Number	PLASMANT @ plasmant @c:irua:196761			Serial	8792
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	Author	Zhao, S.-X.; Zhang, Y.-R.; Gao, F.; Wang, Y.-N.; Bogaerts, A.
	Title	Bulk plasma fragmentation in a C₄F₈ inductively coupled plasma : a hybrid modelling study			Type	A1 Journal article
	Year	2015	Publication	Journal of applied physics	Abbreviated Journal	J Appl Phys
	Volume	117	Issue	117	Pages	243303
	Keywords	A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
	Abstract	A hybrid model is used to investigate the fragmentation of C4F8 inductive discharges. Indeed, the resulting reactive species are crucial for the optimization of the Si-based etching process, since they determine the mechanisms of fluorination, polymerization, and sputtering. In this paper, we present the dissociation degree, the density ratio of F vs. CxFy (i.e., fluorocarbon (fc) neutrals), the neutral vs. positive ion density ratio, details on the neutral and ion components, and fractions of various fc neutrals (or ions) in the total fc neutral (or ion) density in a C4F8 inductively coupled plasma source, as well as the effect of pressure and power on these results. To analyze the fragmentation behavior, the electron density and temperature and electron energy probability function (EEPF) are investigated. Moreover, the main electron-impact generation sources for all considered neutrals and ions are determined from the complicated C4F8 reaction set used in the model. The C4F8 plasma fragmentation is explained, taking into account many factors, such as the EEPF characteristics, the dominance of primary and secondary processes, and the thresholds of dissociation and ionization. The simulation results are compared with experiments from literature, and reasonable agreement is obtained. Some discrepancies are observed, which can probably be attributed to the simplified polymer surface kinetics assumed in the model.
	Address
	Corporate Author				Thesis
	Publisher	American Institute of Physics	Place of Publication	New York, N.Y.	Editor
	Language		Wos	000357613900009	Publication Date	2015-06-30
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0021-8979;1089-7550;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	2.068	Times cited	11	Open Access
	Notes				Approved	Most recent IF: 2.068; 2015 IF: 2.183
	Call Number	c:irua:126477			Serial	261
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	Author	Zhao, S.-X.; Gao, F.; Wang, Y.-P.; Wang, Y.-N.; Bogaerts, A.
	Title	Effects of feedstock availability on the negative ion behavior in a C₄F₈ inductively coupled plasma			Type	A1 Journal article
	Year	2015	Publication	Journal of applied physics	Abbreviated Journal	J Appl Phys
	Volume	118	Issue	118	Pages	033301
	Keywords	A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
	Abstract	In this paper, the negative ion behavior in a C4F8 inductively coupled plasma (ICP) is investigated using a hybrid model. The model predicts a non-monotonic variation of the total negative ion density with power at low pressure (1030 mTorr), and this trend agrees well with experiments that were carried out in many fluorocarbon (fc) ICP sources, like C2F6, CHF3, and C4F8. This behavior is explained by the availability of feedstock C4F8 gas as a source of the negative ions, as well as by the presence of low energy electrons due to vibrational excitation at low power. The maximum of the negative ion density shifts to low power values upon decreasing pressure, because of the more pronounced depletion of C4F8 molecules, and at high pressure (∼50 mTorr), the anion density continuously increases with power, which is similar to fc CCP sources. Furthermore, the negative ion composition is identified in this paper. Our work demonstrates that for a clear understanding of the negative ion behavior in radio frequency C4F8 plasma sources, one needs to take into account many factors, like the attachment characteristics, the anion composition, the spatial profiles, and the reactor configuration. Finally, a detailed comparison of our simulation results with experiments is conducted.
	Address
	Corporate Author				Thesis
	Publisher	American Institute of Physics	Place of Publication	New York, N.Y.	Editor
	Language		Wos	000358429200004	Publication Date	2015-07-20
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0021-8979;1089-7550;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	2.068	Times cited	1	Open Access
	Notes				Approved	Most recent IF: 2.068; 2015 IF: 2.183
	Call Number	c:irua:126735			Serial	861
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	Author	Zhao, S.-X.; Gao, F.; Wang, Y.-N.; Bogaerts, A.
	Title	The effect of F₂ attachment by low-energy electrons on the electron behaviour in an Ar/CF₄ inductively coupled plasma			Type	A1 Journal article
	Year	2012	Publication	Plasma sources science and technology	Abbreviated Journal	Plasma Sources Sci T
	Volume	21	Issue	2	Pages	025008-025008,13
	Keywords	A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
	Abstract	The electron behaviour in an Ar/CF4 inductively coupled plasma is investigated by a Langmuir probe and a hybrid model. The simulated and measured results include electron density, temperature and electron energy distribution function for different values of Ar/CF4 ratio, coil power and gas pressure. The hybrid plasma equipment model simulations show qualitative agreement with experiment. The effect of F2 electron attachment on the electron behaviour is explored by comparing two sets of data based on different F atom boundary conditions. It is demonstrated that electron attachment at F2 molecules is responsible for the depletion of low-energy electrons, causing a density decrease as well as a temperature increase when CF4 is added to an Ar plasma.
	Address
	Corporate Author				Thesis
	Publisher	Institute of Physics	Place of Publication	Bristol	Editor
	Language		Wos	000302779400022	Publication Date	2012-03-12
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0963-0252;1361-6595;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.302	Times cited	23	Open Access
	Notes				Approved	Most recent IF: 3.302; 2012 IF: 2.515
	Call Number	UA @ lucian @ c:irua:96549			Serial	841
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	Author	Zhao, S.-X.; Gao, F.; Wang, Y.-N.; Bogaerts, A.
	Title	Gas ratio effects on the Si etch rate and profile uniformity in an inductively coupled Ar/CF₄ plasma			Type	A1 Journal article
	Year	2013	Publication	Plasma sources science and technology	Abbreviated Journal	Plasma Sources Sci T
	Volume	22	Issue	1	Pages	015017-15018
	Keywords	A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
	Abstract	In this work, a hybrid model is used to investigate the effect of different gas ratios on the Si etching and polymer film deposition characteristics in an Ar/CF4 inductively coupled plasma. The influence of the surface processes on the bulk plasma properties is studied, and also the spatial characteristics of important gas phase and etched species. The densities of F and CF2 decrease when the surface module is included in the simulations, due to the species consumption caused by etching and polymer deposition. The influence of the surface processes on the bulk plasma depends on the Ar/CF4 gas ratio. The deposited polymer becomes thicker at high CF4 content because of more abundant CFx radicals. As a result of the competition between the polymer thickness and the F flux, the etch rate first increases and then decreases upon increasing the CF4 content. The electron properties, more specifically the electron density profile, affect the Si etch characteristics substantially by determining the radical density and flux profiles. In fact, the radial profile of the etch rate is more uniform at low CF4 content since the electron density has a smooth distribution. At high CF4 content, the etch rate is less uniform with a minimum halfway along the wafer radius, because the electron density distribution is more localized. Therefore, our calculations predict that it is better to work at relatively high Ar/CF4 gas ratios, in order to obtain high etch rate and good profile uniformity for etch applications. This, in fact, corresponds to the typical experimental etch conditions in Ar/CF4 gas mixtures as found in the literature, where Ar is typically present at a much higher concentration than CF4.
	Address
	Corporate Author				Thesis
	Publisher	Institute of Physics	Place of Publication	Bristol	Editor
	Language		Wos	000314966300022	Publication Date	2012-12-20
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0963-0252;1361-6595;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.302	Times cited	11	Open Access
	Notes				Approved	Most recent IF: 3.302; 2013 IF: 3.056
	Call Number	UA @ lucian @ c:irua:102583			Serial	1320
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	Author	Zhang, Y.; Wang, H.-yu; Zhang, Y.-ru; Bogaerts, A.
	Title	Formation of microdischarges inside a mesoporous catalyst in dielectric barrier discharge plasmas			Type	A1 Journal article
	Year	2017	Publication	Plasma sources science and technology	Abbreviated Journal	Plasma Sources Sci T
	Volume	26	Issue	26	Pages	054002
	Keywords	A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
	Abstract	The formation process of a microdischarge (MD) in both μm- and nm-sized catalyst pores is simulated by a two-dimensional particle-in-cell/Monte Carlo collision model. A parallel-plate dielectric barrier discharge configuration in filamentary mode is considered in ambient air. The discharge is powered by a high voltage pulse. Our calculations reveal that a streamer can penetrate into the surface features of a porous catalyst and MDs can be formed inside both μm- and nm-sized pores, yielding ionization inside the pore. For the μm-sized pores, the ionization mainly occurs inside the pore, while for the nm-sized pores the ionization is strongest near and inside the pore. Thus, enhanced discharges near and inside the mesoporous catalyst are observed. Indeed, the maximum values of the electric field, ionization rate and electron density occur near and inside the pore. The maximum electric field and electron density inside the pore first increase when the pore size rises from 4 nm to 10 nm, and then they decrease for the 100 nm pore, due to a more pronounced surface discharge for the smaller pores. However, the ionization rate is highest for the 100 nm pore due to the largest effective ionization region.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000399277700001	Publication Date	2017-04-05
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1361-6595	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.302	Times cited	15	Open Access	OpenAccess
	Notes	This work was supported by the NSFC (11405067, 11275007, 11375163). Y Zhang gratefully acknowledges the Belgian Federal Science Policy Office for financial support. The authors are very grateful to Wei Jiang for the useful discussions on the photo-ionization model and the particle-incell/ Monte-Carlo model.			Approved	Most recent IF: 3.302
	Call Number	PLASMANT @ plasmant @ c:irua:142806			Serial	4566
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	Author	Zhang, Y.; Wang, H.-yu; Jiang, W.; Bogaerts, A.
	Title	Two-dimensional particle-in cell/Monte Carlo simulations of a packed-bed dielectric barrier discharge in air at atmospheric pressure			Type	A1 Journal article
	Year	2015	Publication	New journal of physics	Abbreviated Journal	New J Phys
	Volume	17	Issue	17	Pages	083056
	Keywords	A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
	Abstract	The plasma behavior in a parallel-plate dielectric barrier discharge (DBD) is simulated by a two-dimensional particle-in-cell/Monte Carlo collision model, comparing for the first time an unpacked (empty) DBD with a packed bed DBD, i.e., a DBD filled with dielectric spheres in the gas gap. The calculations are performed in air, at atmospheric pressure. The discharge is powered by a pulse with a voltage amplitude of −20 kV. When comparing the packed and unpacked DBD reactors with the same dielectric barriers, it is clear that the presence of the dielectric packing leads to a transition in discharge behavior from a combination of negative streamers and unlimited surface streamers on the bottom dielectric surface to a combination of predominant positive streamers and limited surface discharges on the dielectric surfaces of the beads and plates. Furthermore, in the packed bed DBD, the electric field is locally enhanced inside the dielectric material, near the contact points between the beads and the plates, and therefore also in the plasma between the packing beads and between a bead and the dielectric wall, leading to values of $4\times {10}
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Bristol	Editor
	Language		Wos	000360957800003	Publication Date	2015-08-28
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1367-2630;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.786	Times cited	22	Open Access
	Notes				Approved	Most recent IF: 3.786; 2015 IF: 3.558
	Call Number	c:irua:127650			Serial	3777
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	Author	Zhang, Y.; Jiang, W.; Zhang, Q.Z.; Bogaerts, A.
	Title	Computational study of plasma sustainability in radio frequency micro-discharges			Type	A1 Journal article
	Year	2014	Publication	Journal of applied physics	Abbreviated Journal	J Appl Phys
	Volume	115	Issue	19	Pages	193301-193311
	Keywords	A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
	Abstract	We apply an implicit particle-in-cell Monte-Carlo (PIC-MC) method to study a radio-frequency argon microdischarge at steady state in the glow discharge limit, in which the microdischarge is sustained by secondary electron emission from the electrodes. The plasma density, electron energy distribution function (EEDF), and electron temperature are calculated in a wide range of operating conditions, including driving voltage, microdischarge gap, and pressure. Also, the effect of gap size scaling (in the range of 50-1000 μm) on the plasma sustaining voltage and peak electron density at atmospheric pressure is examined, which has not been explored before. In our simulations, three different EEDFs, i.e., a so-called three temperature hybrid mode, a two temperature α mode, and a two temperature γ mode distribution, are identified at different gaps and voltages. The maximum sustaining voltage to avoid a transition from the glow mode to an arc is predicted, as well as the minimum sustaining voltage for a steady glow discharge. Our calculations elucidate that secondary electrons play an essential role in sustaining the discharge, and as a result the relationship between breakdown voltage and gap spacing is far away from the Paschen law at atmospheric pressure.
	Address
	Corporate Author				Thesis
	Publisher	American Institute of Physics	Place of Publication	New York, N.Y.	Editor
	Language		Wos	000336920200010	Publication Date	2014-05-16
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0021-8979;1089-7550;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	2.068	Times cited	11	Open Access
	Notes				Approved	Most recent IF: 2.068; 2014 IF: 2.183
	Call Number	UA @ lucian @ c:irua:116948			Serial	458
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	Author	Zhang, Y.; Jiang, W.; Bogaerts, A.
	Title	Kinetic simulation of direct-current driven microdischarges in argon at atmospheric pressure			Type	A1 Journal article
	Year	2014	Publication	Journal of physics: D: applied physics	Abbreviated Journal	J Phys D Appl Phys
	Volume	47	Issue	43	Pages	435201
	Keywords	A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
	Abstract	A one-dimensional, implicit particle-in-cell Monte Carlo collision model is used to simulate the plasma kinetic properties at a steady state in a parallel-plate direct current argon glow microdischarge under various operating conditions, such as driving voltage (301000 V) and gap size (101000 µm) at atmospheric pressure. First, a comparison between rf and dc modes is shown for the same pressure, driving voltage and gap spacing. Furthermore, the effect of gap size scaling (in the range of 101000 µm) on the breakdown voltage, peak electron density and peak electron current density at the breakdown voltage is examined. The breakdown voltage is lower than 150 V in all gaps considered. The microdischarge is found to have a neutral bulk plasma region and a cathode sheath region with size varying with the applied voltage and the discharge gap. In our calculations, the electron and ion densities are of the order of 10181023 m−3, which is in the glow discharge limit, as the ionization degree is lower than 1% . The electron energy distribution function shows a two-energy group distribution at a gap of 10 µm and a three-energy group distribution at larger gaps such as 200 µm and 1000 µm, emphasizing the importance of the gap spacing in dc microdischarges.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	London	Editor
	Language		Wos	000343150500011	Publication Date	2014-10-03
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0022-3727;1361-6463;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	2.588	Times cited	10	Open Access
	Notes				Approved	Most recent IF: 2.588; 2014 IF: 2.721
	Call Number	UA @ lucian @ c:irua:119152			Serial	1759
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	Author	Zhang, Y.-R.; Xu, X.; Zhao, S.-X.; Bogaerts, A.; Wang, Y.-N.
	Title	Comparison of electrostatic and electromagnetic simulations for very high frequency plasmas			Type	A1 Journal article
	Year	2010	Publication	Physics of plasmas	Abbreviated Journal	Phys Plasmas
	Volume	17	Issue	11	Pages	113512-113512,11
	Keywords	A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
	Abstract	A two-dimensional self-consistent fluid model combined with the full set of Maxwell equations is developed to investigate an argon capacitively coupled plasma, focusing on the electromagnetic effects on the discharge characteristics at various discharge conditions. The results indicate that there exist distinct differences in plasma characteristics calculated with the so-called electrostatic model (i.e., without taking into account the electromagnetic effects) and the electromagnetic model (which includes the electromagnetic effects), especially at very high frequencies. Indeed, when the excitation source is in the high frequency regime and the electromagnetic effects are taken into account, the plasma density increases significantly and meanwhile the ionization rate evolves to a very different distribution when the electromagnetic effects are dominant. Furthermore, the dependence of the plasma characteristics on the voltage and pressure is also investigated, at constant frequency. It is observed that when the voltage is low, the difference between these two models becomes more obvious than at higher voltages. As the pressure increases, the plasma density profiles obtained from the electromagnetic model smoothly shift from edge-peaked over uniform to a broad maximum in the center. In addition, the edge effect becomes less pronounced with increasing frequency and pressure, and the skin effect rather than the standing-wave effect becomes dominant when the voltage is high.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Woodbury, N.Y.	Editor
	Language		Wos	000285486500105	Publication Date	2010-11-22
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1070-664X;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	2.115	Times cited	30	Open Access
	Notes				Approved	Most recent IF: 2.115; 2010 IF: 2.320
	Call Number	UA @ lucian @ c:irua:84763			Serial	429
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	Author	Zhang, Y.-R.; Xu, X.; Bogaerts, A.; Wang, Y.-N.
	Title	Fluid simulation of the phase-shift effect in hydrogen capacitively coupled plasmas: 1 : transient behaviour of electrodynamics and power deposition			Type	A1 Journal article
	Year	2012	Publication	Journal of physics: D: applied physics	Abbreviated Journal	J Phys D Appl Phys
	Volume	45	Issue	1	Pages	015202-015202,11
	Keywords	A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
	Abstract	A two-dimensional self-consistent fluid model coupled with the full set of Maxwell equations is established to investigate the phase-shift effect on the transient behaviour of electrodynamics and power deposition in a hydrogen capacitively coupled plasma. The effect has been examined at 13.56 MHz and 100 MHz, respectively, because of the different phase-shift modulation when the electromagnetic effects are dominant. The results indicate that the spatiotemporal distributions of the plasma characteristics obtained for various phase-shift cases are obviously different both in shape and especially in absolute values. Indeed, when the phase difference varies from 0 to π, there is an increase in the electron flux, thus the power deposition becomes more pronounced. At the frequency of 13.56 MHz, the axial electron flux in the bulk plasma becomes uniform along the z-axis, and the radial electron flux exhibits two peaks within one period at the reverse-phase case, whereas the oscillation is less pronounced at the in-phase case. Furthermore, in the very high frequency discharge, the radial electron flux is alternately positive and negative with four peaks during one period, and the ionization mainly occurs in the sheath region, due to the prominent power deposition there at a phase difference equal to π.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	London	Editor
	Language		Wos	000298290000011	Publication Date	2011-12-12
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0022-3727;1361-6463;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	2.588	Times cited	57	Open Access
	Notes				Approved	Most recent IF: 2.588; 2012 IF: 2.528
	Call Number	UA @ lucian @ c:irua:92851			Serial	1230
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	Author	Zhang, Y.-R.; Xu, X.; Bogaerts, A.; Wang, Y.-N.
	Title	Fluid simulation of the phase-shift effect in hydrogen capacitively coupled plasmas: 2 : radial uniformity of the plasma characteristics			Type	A1 Journal article
	Year	2012	Publication	Journal of physics: D: applied physics	Abbreviated Journal	J Phys D Appl Phys
	Volume	45	Issue	1	Pages	015203-015203,13
	Keywords	A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
	Abstract	A two-dimensional fluid model, including the full set of Maxwell equations, has been developed and applied to investigate the effect of a phase shift between two power sources on the radial uniformity of several plasma characteristics in a hydrogen capacitively coupled plasma. This study was carried out at various frequencies in the range 13.56200 MHz. When the frequency is low, at 13.56 MHz, the plasma density is characterized by an off-axis peak when both power sources are in-phase (phgr = 0), and the best radial uniformity is obtained at phgr = π. This trend can be explained because the radial nonuniformity caused by the electrostatic edge effect can be effectively suppressed by the phase-shift effect at a phase difference equal to π. When the frequency rises to 60 MHz, the plasma density profiles shift smoothly from edge-peaked over uniform to centre-peaked as the phase difference increases, due to the pronounced standing-wave effect, and the best radial uniformity is reached at phgr = 0.3π. At a frequency of 100 MHz, a similar behaviour is observed, except that the maximum of the plasma density moves again towards the radial edge at the reverse-phase case (phgr = π), because of the dominant skin effect. When the frequency is 200 MHz, the bulk plasma density increases significantly with increasing phase-shift values, and a better uniformity is obtained at phgr = 0.4π. This is because the density in the centre increases faster than at the radial edge as the phase difference rises, due to the increasing power deposition Pz in the centre and the decreasing power density Pr at the radial edge. As the phase difference increases to π, the maximum near the radial edge becomes obvious again. This is because the skin effect has a predominant influence on the plasma density under this condition, resulting in a high density at the radial edge. Moreover, the axial ion flux increases monotonically with phase difference, and exhibits similar profiles to the plasma density. The calculation results illustrate that the radial uniformity of the various plasma characteristics is strongly dependent on the applied frequency and the phase shift between both power sources, which is important to realize, for controlling the uniformity of the plasma etch and deposition processes.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	London	Editor
	Language		Wos	000298290000012	Publication Date	2011-12-12
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0022-3727;1361-6463;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	2.588	Times cited	15	Open Access
	Notes				Approved	Most recent IF: 2.588; 2012 IF: 2.528
	Call Number	UA @ lucian @ c:irua:92852			Serial	1231
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	Author	Zhang, Y.-R.; Van Laer, K.; Neyts, E.C.; Bogaerts, A.
	Title	Can plasma be formed in catalyst pores? A modeling investigation			Type	A1 Journal article
	Year	2016	Publication	Applied catalysis : B : environmental	Abbreviated Journal	Appl Catal B-Environ
	Volume	185	Issue	185	Pages	56-67
	Keywords	A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
	Abstract	tWe investigate microdischarge formation inside catalyst pores by a two-dimensional fluid model forvarious pore sizes in the m-range and for various applied voltages. Indeed, this is a poorly understoodphenomenon in plasma catalysis. The calculations are performed for a dielectric barrier discharge inhelium, at atmospheric pressure. The electron and ion densities, electron temperature, electric field andpotential, as well as the electron impact ionization and excitation rate and the densities of excited plasmaspecies, are examined for a better understanding of the characteristics of the plasma inside a pore. Theresults indicate that the pore size and the applied voltage are critical parameters for the formation of amicrodischarge inside a pore. At an applied voltage of 20 kV, our calculations reveal that the ionizationmainly takes place inside the pore, and the electron density shows a significant increase near and inthe pore for pore sizes larger than 200m, whereas the effect of the pore on the total ion density isevident even for 10m pores. When the pore size is fixed at 30m, the presence of the pore has nosignificant influence on the plasma properties at an applied voltage of 2 kV. Upon increasing the voltage,the ionization process is enhanced due to the strong electric field and high electron temperature, andthe ion density shows a remarkable increase near and in the pore for voltages above 10 kV. These resultsindicate that the plasma species can be formed inside pores of structured catalysts (in the m range),and they may interact with the catalyst surface, and affect the plasma catalytic process.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000369452000006	Publication Date	2015-12-11
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0926-3373	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	9.446	Times cited	75	Open Access
	Notes	This work was supported by the Fund for Scientific ResearchFlanders (FWO) (Grant no. G.0217.14N), the National Natural Sci-ence Foundation of China (Grant no. 11405019), and the ChinaPostdoctoral Science Foundation (Grant no. 2015T80244). Theauthors are very grateful to V. Meynen for the useful discussions oncatalysts. This work was carried out in part using the Turing HPCinfrastructure at the CalcUA core facility of the Universiteit Antwer-pen, a division of the Flemish Supercomputer Center VSC, fundedby the Hercules Foundation, the Flemish Government (departmentEWI) and the University of Antwerp.			Approved	Most recent IF: 9.446
	Call Number	c:irua:129808			Serial	3984
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	Author	Zhang, Y.-R.; Tinck, S.; De Schepper, P.; Wang, Y.-N.; Bogaerts, A.
	Title	Modeling and experimental investigation of the plasma uniformity in CF₄/O₂ capacitively coupled plasmas, operating in single frequency and dual frequency regime			Type	A1 Journal article
	Year	2015	Publication	Journal of vacuum science and technology: A: vacuum surfaces and films	Abbreviated Journal	J Vac Sci Technol A
	Volume	33	Issue	33	Pages	021310
	Keywords	A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
	Abstract	A two-dimensional hybrid Monte Carlofluid model, incorporating a full-wave solution of Maxwell's equations, is employed to describe the behavior of high frequency (HF) and very high frequency capacitively coupled plasmas (CCPs), operating both at single frequency (SF) and dual frequency (DF) in a CF4/O2 gas mixture. First, the authors investigate the plasma composition, and the simulations reveal that besides CF4 and O2, also COF2, CF3, and CO2 are important neutral species, and CF+3 and F− are the most important positive and negative ions. Second, by comparing the results of the model with and without taking into account the electromagnetic effects for a SF CCP, it is clear that the electromagnetic effects are important, both at 27 and 60 MHz, because they affect the absolute values of the calculation results and also (to some extent) the spatial profiles, which accordingly affects the uniformity in plasma processing. In order to improve the plasma radial uniformity, which is important for the etch process, a low frequency (LF) source is added to the discharge. Therefore, in the major part of the paper, the plasma uniformity is investigated for both SF and DF CCPs, operating at a HF of 27 and 60 MHz and a LF of 2 MHz. For this purpose, the authors measure the etch rates as a function of position on the wafer in a wide range of LF powers, and the authors compare them with the calculated fluxes toward the wafer of the plasma species playing a role in the etch process, to explain the trends in the measured etch rate profiles. It is found that at a HF of 60 MHz, the uniformity of the etch rate is effectively improved by adding a LF power of 2 MHz and 300 W, while its absolute value increases by about 50%, thus a high etch rate with a uniform distribution is observed under this condition.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	New York, N.Y.	Editor
	Language		Wos	000355739500026	Publication Date	2015-01-29
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0734-2101;1520-8559;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	1.374	Times cited	3	Open Access
	Notes				Approved	Most recent IF: 1.374; 2015 IF: 2.322
	Call Number	c:irua:122650			Serial	2107
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	Author	Zhang, Y.-R.; Neyts, E.C.; Bogaerts, A.
	Title	Influence of the Material Dielectric Constant on Plasma Generation inside Catalyst Pores			Type	A1 Journal article
	Year	2016	Publication	The journal of physical chemistry: C : nanomaterials and interfaces	Abbreviated Journal	J Phys Chem C
	Volume	120	Issue	120	Pages	25923-25934
	Keywords	A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
	Abstract	Plasma catalysis is gaining increasing interest for various environmental applications, but the crucial question is whether plasma can be created inside catalyst pores and under which conditions. In practice, various catalytic support materials are used, with various dielectric constants. We investigate here the influence of the dielectric constant on the plasma properties inside catalyst pores and in the sheath in front of the pores, for various pore sizes. The calculations are performed by a two-dimensional fluid model for an atmospheric pressure dielectric barrier discharge in helium. The electron impact ionization rate, electron temperature, electron and ion density, as well as the potential distribution and surface charge density, are analyzed for a better understanding of the discharge behavior inside catalyst pores. The results indicate that, in a 100 μm pore, the electron impact ionization in the pore, which is characteristic for the plasma generation inside the pore, is greatly enhanced for dielectric constants below 300. Smaller pore sizes only yield enhanced ionization for smaller dielectric constants, i.e., up to εr = 200, 150, and 50 for pore sizes of 50, 30, and 10 μm. Thus, the most common catalyst supports, i.e., Al2O3 and SiO2, which have dielectric constants around εr = 8−11 and 4.2, respectively, should allow more easily that microdischarges can be formed inside catalyst pores, even for smaller pore sizes. On the other hand, ferroelectric materials with dielectric constants above 300 never seem to yield plasma enhancement inside catalyst pores, not even for 100 μm pore sizes. Furthermore, it is clear that the dielectric constant of the material has a large effect on the extent of plasma enhancement inside the catalyst pores, especially in the range between εr = 4 and εr = 200. The obtained results are explained in detail based on the surface charge density at the pore walls, and the potential distribution and electron temperature inside and above the pores. The results obtained with this model are important for plasma catalysis, as the production plasma species in catalyst pores might affect the catalyst properties, and thus improve the applications of plasma catalysis.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000388429100029	Publication Date	2016-11-17
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1932-7447	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	4.536	Times cited	34	Open Access
	Notes	This work was supported by the Fund for Scientific Research Flanders (FWO) (Grant G.0217.14N), the National Natural Science Foundation of China (Grant 11405019), and the China Postdoctoral Science Foundation (Grant 2015T80244). This work was carried out in part using the Turing HPC infrastructure at the CalcUA core facility of the Universiteit Antwerpen, a division of the Flemish Supercomputer Center VSC, funded by the Hercules Foundation, the Flemish Government (department EWI), and the University of Antwerp.			Approved	Most recent IF: 4.536
	Call Number	PLASMANT @ plasmant @ c:irua:138602			Serial	4319
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	Author	Zhang, Y.-R.; Neyts, E.C.; Bogaerts, A.
	Title	Enhancement of plasma generation in catalyst pores with different shapes			Type	A1 Journal article
	Year	2018	Publication	Plasma sources science and technology	Abbreviated Journal	Plasma Sources Sci T
	Volume	27	Issue	5	Pages	055008
	Keywords	A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
	Abstract	Plasma generation inside catalyst pores is of utmost importance for plasma catalysis, as the existence of plasma species inside the pores affects the active surface area of the catalyst available to the plasma species for catalytic reactions. In this paper, the electric field enhancement, and thus the plasma production inside catalyst pores with different pore shapes is studied with a two-dimensional fluid model. The results indicate that the electric field will be significantly enhanced near tip-like structures. In a conical pore with small opening, the strongest electric field appears at the opening and bottom corners of the pore, giving rise to a prominent ionization rate throughout the pore. For a cylindrical pore, the electric field is only enhanced at the bottom corners of the pore, with lower absolute value, and thus the ionization rate inside the pore is only slightly enhanced. Finally, in a conical pore with large opening, the electric field is characterized by a maximum at the bottom of the pore, yielding a similar behavior for the ionization rate. These results demonstrate that the shape of the pore has a significantly influence on the electric field enhancement, and thus modifies the plasma properties.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000432351700002	Publication Date	2018-05-15
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1361-6595	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.302	Times cited	11	Open Access	OpenAccess
	Notes	This work was supported by the Fund for Scientific Research Flanders (FWO) (Grant No. G.0217.14N) and the Fundamental Research Funds for the Central Universities (Grant No. DUT17LK52).			Approved	Most recent IF: 3.302
	Call Number	PLASMANT @ plasmant @c:irua:151546			Serial	4998
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	Author	Zhang, Y.-R.; Gao, F.; Li, X.-C.; Bogaerts, A.; Wang, Y.-N.
	Title	Fluid simulation of the bias effect in inductive/capacitive discharges			Type	A1 Journal article
	Year	2015	Publication	Journal of vacuum science and technology: A: vacuum surfaces and films	Abbreviated Journal	J Vac Sci Technol A
	Volume	33	Issue	33	Pages	061303
	Keywords	A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
	Abstract	Computer simulations are performed for an argon inductively coupled plasma (ICP) with a capacitive radio-frequency bias power, to investigate the bias effect on the discharge mode transition and on the plasma characteristics at various ICP currents, bias voltages, and bias frequencies. When the bias frequency is fixed at 13.56 MHz and the ICP current is low, e.g., 6A, the spatiotemporal averaged plasma density increases monotonically with bias voltage, and the bias effect is already prominent at a bias voltage of 90 V. The maximum of the ionization rate moves toward the bottom electrode, which indicates clearly the discharge mode transition in inductive/capacitive discharges. At higher ICP currents, i.e., 11 and 13 A, the plasma density decreases first and then increases with bias voltage, due to the competing mechanisms between the ion acceleration power dissipation and the capacitive power deposition. At 11 A, the bias effect is still important, but it is noticeable only at higher bias voltages. At 13 A, the ionization rate is characterized by a maximum at the reactor center near the dielectric window at all selected bias voltages, which indicates that the ICP power, instead of the bias power, plays a dominant role under this condition, and no mode transition is observed. Indeed, the ratio of the bias power to the total power is lower than 0.4 over a wide range of bias voltages, i.e., 0300V. Besides the effect of ICP current, also the effect of various bias frequencies is investigated. It is found that the modulation of the bias power to the spatiotemporal distributions of the ionization rate at 2MHz is strikingly different from the behavior observed at higher bias frequencies. Furthermore, the minimum of the plasma density appears at different bias voltages, i.e., 120V at 2MHz and 90V at 27.12 MHz.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000365503800020	Publication Date	2015-08-07
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0734-2101;1520-8559;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	1.374	Times cited	9	Open Access
	Notes				Approved	Most recent IF: 1.374; 2015 IF: 2.322
	Call Number	c:irua:126824			Serial	1229
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	Author	Zhang, Y.-R.; Bogaerts, A.; Wang, Y.-N.
	Title	Fluid simulation of the phase-shift effect in Ar/CF₄ capacitively coupled plasmas			Type	A1 Journal article
	Year	2012	Publication	Journal of physics: D: applied physics	Abbreviated Journal	J Phys D Appl Phys
	Volume	45	Issue	48	Pages	485204
	Keywords	A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
	Abstract	A two-dimensional self-consistent fluid model combined with the full set of Maxwell equations is employed to investigate an Ar/CF4 capacitively coupled plasma, focusing on the phase-shift effect on the plasma characteristics at various frequencies and gas mixture ratios. When the discharge is sustained by a single frequency at 13.56 MHz in an Ar/CF4 mixture with a ratio of 0.9/0.1, no obvious difference is detected between the electron densities obtained in the so-called electrostatic model (with only the static electric fields taken into account) and the electromagnetic model (which includes the electromagnetic effects). However, as the frequency increases to 60 and 100 MHz, the difference becomes distinct, due to the significant influence of the electromagnetic effects. The phase-shift effect on the plasma radial uniformity has also been investigated in a dual frequency discharge, i.e. when the top driven source is switched on with a phase difference phiv ranging from 0 to π, in the frequency range 13.56100 MHz. At low concentration of CF4 (10%), Ar+ ions are the major positive ions in the entire range of frequencies. When the frequency is low, i.e. 13.56 MHz, the Ar+ density exhibits an off-axis peak at phiv = 0 due to the edge effect, and a better uniformity caused by the phase-shift modulation is obtained at phiv = π. At 60 MHz, the Ar+ density varies from edge-peaked at phiv = 0 to uniform (i.e. at phiv = 0.53π), and finally at phiv = π, a broad maximum is observed at the centre due to the standing-wave effect. As the frequency increases to 100 MHz, the best radial uniformity is reached at 0.25π, and the maximum moves again towards the radial wall in the reverse-phase case (phiv = π) due to the dominant skin effect. When the frequency is fixed at 100 MHz, the phase-shift control shows a different behaviour at a high concentration of CF4. For instance, the ${\rm CF}_3
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	London	Editor
	Language		Wos	000311148300011	Publication Date	2012-11-06
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0022-3727;1361-6463;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	2.588	Times cited	8	Open Access
	Notes				Approved	Most recent IF: 2.588; 2012 IF: 2.528
	Call Number	UA @ lucian @ c:irua:101754			Serial	1232
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	Author	Zhang, S.; Van Gaens, W.; van Gessel, B.; Hofmann, S.; van Veldhuizen, E.; Bogaerts, A.; Bruggeman, P.
	Title	Spatially resolved ozone densities and gas temperatures in a time modulated RF driven atmospheric pressure plasma jet : an analysis of the production and destruction mechanisms			Type	A1 Journal article
	Year	2013	Publication	Journal of physics: D: applied physics	Abbreviated Journal	J Phys D Appl Phys
	Volume	46	Issue	20	Pages	205202-205212
	Keywords	A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
	Abstract	In this work, a time modulated RF driven DBD-like atmospheric pressure plasma jet in Ar + 2%O2, operating at a time averaged power of 6.5 W is investigated. Spatially resolved ozone densities and gas temperatures are obtained by UV absorption and Rayleigh scattering, respectively. Significant gas heating in the core of the plasma up to 700 K is found and at the position of this increased gas temperature a depletion of the ozone density is found. The production and destruction reactions of O3 in the jet effluent as a function of the distance from the nozzle are obtained from a zero-dimensional chemical kinetics model in plug flow mode which considers relevant air chemistry due to air entrainment in the jet fluent. A comparison of the measurements and the models show that the depletion of O3 in the core of the plasma is mainly caused by an enhanced destruction of O3 due to a large atomic oxygen density.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	London	Editor
	Language		Wos	000318546100008	Publication Date	2013-05-02
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0022-3727;1361-6463;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	2.588	Times cited	74	Open Access
	Notes				Approved	Most recent IF: 2.588; 2013 IF: 2.521
	Call Number	UA @ lucian @ c:irua:107840			Serial	3067
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	Author	Zhang, Q.‐Z.; Zhang, L.; Yang, D.‐Z.; Schulze, J.; Wang, Y.‐N.; Bogaerts, A.
	Title	Positive and negative streamer propagation in volume dielectric barrier discharges with planar and porous electrodes			Type	A1 Journal article
	Year	2021	Publication	Plasma Processes And Polymers	Abbreviated Journal	Plasma Process Polym
	Volume	18	Issue	4	Pages	2000234
	Keywords	A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
	Abstract	The spatiotemporal dynamics of volume and surface positive and negative streamers in a pintoplate volume dielectric barrier discharge is investigated in this study. The discharge characteristics are found to be completely different for positive and negative streamers. First, the spatial propagation of a positive streamer is found to rely on electron avalanches caused by photo-electrons in front of the streamer head, whereas this is not the case for negative streamers. Second, our simulations reveal an interesting phenomenon of floating positive surface discharges, which develop when a positive streamer reaches a dielectric wall and which explain the experimentally observed branching characteristics. Third, we report for the first time, the interactions between a positive streamer and dielectric pores, in which both the pore diameter and depth affect the evolution of a positive streamer.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000617876700001	Publication Date	2021-02-17
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1612-8850	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	2.846	Times cited		Open Access	OpenAccess
	Notes	Dalian University of Technology, DUT19RC(3)045 ; National Natural Science Foundation of China, 12020101005 ; Deutsche Forschungsgemeinschaft, SFB 1316 project A5 ; Universiteit Antwerpen, TOP‐BOF ; The authors acknowledge financial support from the TOP-BOF project of the University of Antwerp. This study was carried out in part using the Turing HPC infrastructure at the CalcUA core facility of the Universiteit Antwerpen, a division of the Flemish Supercomputer Center VSC, funded by the Hercules Foundation, the Flemish Government (Department EWI), and the University of Antwerp. Funding by the German Research Foundation (DFG) in the frame of the Collaborative Research Center SFB 1316, project A5, National Natural Science Foundation of China (No. 12020101005), and the Scientific Research Foundation from Dalian University of Technology (DUT19RC(3)045) is also acknowledged.			Approved	Most recent IF: 2.846
	Call Number	PLASMANT @ plasmant @c:irua:176565			Serial	6744
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	Author	Zhang, Q.-Z.; Zhao, S.-X.; Jiang, W.; Wang, Y.-N.
	Title	Separate control between geometrical and electrical asymmetry effects in capacitively coupled plasmas			Type	A1 Journal article
	Year	2012	Publication	Journal of physics: D: applied physics	Abbreviated Journal	J Phys D Appl Phys
	Volume	45	Issue	30	Pages	305203
	Keywords	A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
	Abstract	Both geometrical and electrical asymmetry effects in capacitive argon discharges are investigated using a two-dimensional particle-in-cell coupled with Monte Carlo collision model. When changing the ratio of the top and bottom electrode surface areas and the phase shift between the two applied harmonics, the induced self-bias was found to develop separately. By adjusting the ratio between the high and low harmonic amplitudes, the electrical asymmetry effect at a fixed phase shift can be substantially optimized. However, the self-bias caused by the geometrical asymmetry hardly changed. Moreover, the separate control of these two asymmetry effects can also be demonstrated from their power absorption profiles. Both the axial and radial plasma density distributions can be modulated by the electrical asymmetry effect.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	London	Editor
	Language		Wos	000306475200007	Publication Date	2012-07-10
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0022-3727;1361-6463;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	2.588	Times cited	20	Open Access
	Notes				Approved	Most recent IF: 2.588; 2012 IF: 2.528
	Call Number	UA @ lucian @ c:irua:100751			Serial	2984
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	Author	Zhang, Q.-Z.; Wang, Y.-N.; Bogaerts, A.
	Title	Heating mode transition in a hybrid direct current/dual-frequency capacitively coupled CF₄ discharge			Type	A1 Journal article
	Year	2014	Publication	Journal of applied physics	Abbreviated Journal	J Appl Phys
	Volume	115	Issue	22	Pages	223302-223306
	Keywords	A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
	Abstract	Computer simulations based on the particle-in-cell/Monte Carlo collision method are performed to study the plasma characteristics and especially the transition in electron heating mechanisms in a hybrid direct current (dc)/dual-frequency (DF) capacitively coupled CF 4 discharge. When applying a superposed dc voltage, the plasma density first increases, then decreases, and finally increases again, which is in good agreement with experiments. This trend can be explained by the transition between the four main heating modes, i.e., DF coupling, dc and DF coupling, dc source dominant heating, and secondary electron dominant heating.
	Address
	Corporate Author				Thesis
	Publisher	American Institute of Physics	Place of Publication	New York, N.Y.	Editor
	Language		Wos	000337891800006	Publication Date	2014-06-11
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0021-8979;1089-7550;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	2.068	Times cited	9	Open Access
	Notes				Approved	Most recent IF: 2.068; 2014 IF: 2.183
	Call Number	UA @ lucian @ c:irua:117347			Serial	1414
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	Author	Zhang, Q.-Z.; Wang, W.Z.; Thille, C.; Bogaerts, A.
	Title	H2S Decomposition into H2 and S2 by Plasma Technology: Comparison of Gliding Arc and Microwave Plasma			Type	A1 Journal article
	Year	2020	Publication	Plasma Chemistry And Plasma Processing	Abbreviated Journal	Plasma Chem Plasma P
	Volume	40	Issue	5	Pages	1163-1187
	Keywords	A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
	Abstract	We studied hydrogen sulfide (H2S) decomposition into hydrogen (H2) and sulfur (S2) in a gliding arc plasmatron (GAP) and microwave (MW) plasma by a combination of 0D and 2D models. The conversion, energy efficiency, and plasma distribution are examined for different discharge conditions, and validated with available experiments from literature. Furthermore, a comparison is made between GAP and MW plasma. The GAP operates at atmospheric pressure, while the MW plasma experiments to which comparison is made were performed at reduced pressure. Indeed, the MW discharge region becomes very much contracted near atmospheric pressure, at the conditions under study, as revealed by our 2D model. The models predict that thermal reactions play the most important role in H2S decomposition in both plasma types. The GAP has a higher energy efficiency but lower conversion than the MW plasma at their typical conditions. When compared at the same conversion, the GAP exhibits a higher energy efficiency and lower energy cost than the MW plasma.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000543012200001	Publication Date	2020-06-24
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0272-4324	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.6	Times cited		Open Access
	Notes	This work was supported by the Scientific Research Foundation from Dalian University of Technology, DUT19RC(3)045. We gratefully acknowledge T. Godfroid (Materia Nova) for sharing the experimental data about the MW plasma. The calculations were performed using the Turing HPC infrastructure at the CalcUA core facility of the Universiteit Antwerpen (UAntwerpen), a division of the Flemish Supercomputer Center VSC, funded by the Hercules Foundation, the Flemish Government (department EWI) and the UAntwerpen.			Approved	Most recent IF: 3.6; 2020 IF: 2.355
	Call Number	PLASMANT @ plasmant @c:irua:172490			Serial	6409
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	Author	Zhang, Q.-Z.; Wang, W.-Z.; Bogaerts, A.
	Title	Importance of surface charging during plasma streamer propagation in catalyst pores			Type	A1 Journal article
	Year	2018	Publication	Plasma sources science and technology	Abbreviated Journal	Plasma Sources Sci T
	Volume	27	Issue	6	Pages	065009
	Keywords	A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
	Abstract	Plasma catalysis is gaining increasing interest, but the underlying mechanisms are far from understood. Different catalyst materials will have different chemical effects, but in addition, they might also have different dielectric constants, which will affect surface charging, and thus the plasma behavior. In this work, we demonstrate that surface charging plays an important role in the streamer propagation and discharge enhancement inside catalyst pores, and in the plasma distribution along the dielectric surface, and this role greatly depends on the dielectric constant of the material. For εr50, surface charging causes the plasma to spread along the dielectric surface and inside the pores, leading to deeper plasma streamer penetration, while for εr>50 or for metallic coatings, the discharge is more localized, due to very weak surface charging. In addition, at εr=50, the significant surface charge density near the pore entrance causes a large potential drop at the sharp pore edges, which induces a strong electric field and results in most pronounced plasma enhancement near the pore entrance.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000436845700002	Publication Date	2018-06-27
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1361-6595	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.302	Times cited	13	Open Access	OpenAccess
	Notes	We acknowledge financial support from the European Marie Skłodowska-Curie Individual Fellowship within H2020 (Grant Agreement 702604) and from the TOP-BOF project of the University of Antwerp. This work was carried out in part using the Turing HPC infrastructure at the CalcUA core facility of the Universiteit Antwerpen, a division of the Flemish Supercomputer Center VSC, funded by the Hercules Foundation, the Flemish Government (department EWI) and the University of Antwerp.			Approved	Most recent IF: 3.302
	Call Number	PLASMANT @ plasmant @c:irua:152243			Serial	4995
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	Author	Zhang, Q.-Z.; Tinck, S.; de Marneffe, J.-F.; Zhang, L.; Bogaerts, A.
	Title	Mechanisms for plasma cryogenic etching of porous materials			Type	A1 Journal article
	Year	2017	Publication	Applied physics letters	Abbreviated Journal	Appl Phys Lett
	Volume	111	Issue	17	Pages	173104
	Keywords	A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
	Abstract	Porous materials are commonly used in microelectronics, as they can meet the demand for continuously shrinking electronic feature dimensions. However, they are facing severe challenges in plasma etching, due to plasma induced damage. In this paper, we present both the plasma characteristics and surface processing during the etching of porous materials. We explain how the damage occurs in the porous material during plasma etching for a wide range of chuck temperatures and the responsible mechanism for plasma damage-free etching at cryogenic temperature, by a combination of experiments and numerical modeling.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000413863400032	Publication Date	2017-10-23
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0003-6951	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.411	Times cited	2	Open Access	OpenAccess
	Notes	We acknowledge the support from Marie Skłodowska- Curie actions (Grant Agreement-702604). This work was carried out in part using the Turing HPC infrastructure at the CalcUA core facility of Universiteit Antwerpen, a division of the Flemish Supercomputer Center VSC, funded by the Hercules Foundation, the Flemish Government (department EWI), and the University of Antwerp. L. Zhang and J.-F. de Marneffe acknowledge Dr. M. Cooke and A. Goodyear from Oxford Instruments Plasma Technology for processing the samples at their Yatton facility in the United Kingdom.			Approved	Most recent IF: 3.411
	Call Number	PLASMANT @ plasmant @c:irua:147022			Serial	4762
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	Author	Zhang, Q.-Z.; Liu, Y.-X.; Jiang, W.; Bogaerts, A.; Wang, Y.-N.
	Title	Heating mechanism in direct current superposed single-frequency and dual-frequency capacitively coupled plasmas			Type	A1 Journal article
	Year	2013	Publication	Plasma sources science and technology	Abbreviated Journal	Plasma Sources Sci T
	Volume	22	Issue	2	Pages	025014-25018
	Keywords	A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
	Abstract	In this work particle-in-cell/Monte Carlo collision simulations are performed to study the heating mechanism and plasma characteristics in direct current (dc) superposed radio-frequency (RF) capacitively coupled plasmas, operated both in single-frequency (SF) and dual-frequency (DF) regimes. An RF (60/2 MHz) source is applied on the bottom electrode to sustain the discharge, and a dc source is fixed on the top electrode. The heating mechanism appears to be very different in dc superposed SF and DF discharges. When only a single source of 60 MHz is applied, the plasma bulk region is reduced by the dc source, thus the ionization rate and hence the electron density decrease with rising dc voltage. However, when a DF source of 60 and 2 MHz is applied, the electron density can increase upon addition of a dc voltage, depending on the gap length and applied dc voltage. This is explained from the spatiotemporal ionization rates in the DF discharge. In fact, a completely different behavior is observed for the ionization rate in the two half-periods of the LF source. In the first LF half-period, the situation resembles the dc superposed SF discharge, and the reduced plasma bulk region due to the negative dc bias results in a very small effective discharge area and a low ionization rate. On the other hand, in the second half-period, the negative dc bias is to some extent counteracted by the LF voltage, and the sheath close to the dc electrode becomes particularly thin. Consequently, the amplitude of the high-frequency sheath oscillations at the top electrode is largely enhanced, while the LF sheath at the bottom electrode is in its expanding phase and can thus well confine the high-energy electrons. Therefore, the ionization rate increases considerably in this second LF half-period. Furthermore, in addition to the comparison between SF and DF discharges and the effect of gap length and dc voltage, the effect of secondary electrons is examined.
	Address
	Corporate Author				Thesis
	Publisher	Institute of Physics	Place of Publication	Bristol	Editor
	Language		Wos	000317275400016	Publication Date	2013-03-28
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0963-0252;1361-6595;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.302	Times cited	9	Open Access
	Notes				Approved	Most recent IF: 3.302; 2013 IF: 3.056
	Call Number	UA @ lucian @ c:irua:106877			Serial	1413
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	Author	Zhang, Q.-Z.; Bogaerts, A.
	Title	Propagation of a plasma streamer in catalyst pores			Type	A1 Journal article
	Year	2018	Publication	Plasma sources science and technology	Abbreviated Journal	Plasma Sources Sci T
	Volume	27	Issue	3	Pages	035009
	Keywords	A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
	Abstract	Although plasma catalysis is gaining increasing interest for various environmental applications, the underlying mechanisms are still far from understood. For instance, it is not yet clear whether and how plasma streamers can propagate in catalyst pores, and what is the minimum pore size to make this happen. As this is crucial information to ensure good plasma-catalyst interaction, we study here the mechanism of plasma streamer propagation in a catalyst pore, by means of a twodimensional particle-in-cell/Monte Carlo collision model, for various pore diameters in the nm range to μm-range. The so-called Debye length is an important criterion for plasma penetration into catalyst pores, i.e. a plasma streamer can penetrate into pores when their diameter is larger than the Debye length. The Debye length is typically in the order of a few 100 nm up to 1 μm at the conditions under study, depending on electron density and temperature in the plasma streamer. For pores in the range of ∼50 nm, plasma can thus only penetrate to some extent and at very short times, i.e. at the beginning of a micro-discharge, before the actual plasma streamer reaches the catalyst surface and a sheath is formed in front of the surface. We can make plasma streamers penetrate into smaller pores (down to ca. 500 nm at the conditions under study) by increasing the applied voltage, which yields a higher plasma density, and thus reduces the Debye length. Our simulations also reveal that the plasma streamers induce surface charging of the catalyst pore sidewalls, causing discharge enhancement inside the pore, depending on pore diameter and depth.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000427976800001	Publication Date	2018-03-20
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1361-6595	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.302	Times cited	16	Open Access	OpenAccess
	Notes	We acknowledge financial support from the European Marie Skłodowska-Curie Individual Fellowship within H2020 (Grant Agreement 702604) and from the Fund for Scientific Research Flanders (FWO) (Excellence of Science Program; EOS ID 30505023). This work was carried out in part using the Turing HPC infrastructure at the CalcUA core facility of the Universiteit Antwerpen, a division of the Flemish Supercomputer Center VSC, funded by the Hercules Foundation, the Flemish Government (department EWI) and the University of Antwerp.			Approved	Most recent IF: 3.302
	Call Number	PLASMANT @ plasmant @c:irua:150877			Serial	4954
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