Abstract: We report a plasma‐assisted CO₂hydrogenation to CH₃OH over Fe₂O₃/γ‐Al₂O₃catalysts, achieving 12% CO₂conversion and 58% CH₃OH selectivity at a temperature of nearly 80°C atm pressure. We investigated the effect of various supports and loadings of the Fe‐based catalysts, as well as optimized reaction conditions. We characterized catalysts by X‐ray powder diffraction (XRD), hydrogen temperature programmed reduction (H₂‐TPR), CO₂and CO temperature programmed desorption (CO₂/CO‐TPD), high‐resolution transmission electron microscopy (HRTEM), scanning transmission electron microscopy (STEM), x‐ray photoelectron spectroscopy (XPS), Mössbauer, and Fourier transform infrared<bold>(</bold>FTIR). The XPS results show that the enhanced CO₂conversion and CH₃OH selectivity are attributed to the chemisorbed oxygen species on Fe₂O₃/γ‐Al₂O₃. Furthermore, the diffuse reflectance infrared Fourier transform spectroscopy (DRIFTs) and TPD results illustrate that the catalysts with stronger CO₂adsorption capacity exhibit a higher reaction performance.<italic>In situ</italic>DRIFTS gain insight into the specific reaction pathways in the CO₂/H₂plasma. This study reveals the role of chemisorbed oxygen species as a key intermediate, and inspires to design highly efficient catalysts and expand the catalytic systems for CO₂hydrogenation to CH₃OH.

Abstract: Lanthanide-doped LiYF4 (Ln:YLF) is commonlyused fora broad variety of optical applications, such as lasing, photon upconversionand optical refrigeration. When synthesized as nanocrystals (NCs),this material is also of interest for biological applications andfundamental physical studies. Until now, it was unclear how Ln:YLFNCs grow from their ionic precursors into tetragonal NCs with a well-defined,bipyramidal shape and uniform dopant distribution. Here, we studythe nucleation and growth of ytterbium-doped LiYF4 (Yb:YLF),as a template for general Ln:YLF NC syntheses. We show that the formationof bipyramidal Yb:YLF NCs is a multistep process starting with theformation of amorphous Yb:YLF spheres. Over time, these spheres growvia Ostwald ripening and crystallize, resulting in bipyramidal Yb:YLFNCs. We further show that prolonged heating of the NCs results inthe degradation of the NCs, observed by the presence of large LiFcubes and small, irregular Yb:YLF NCs. Due to the similarity in chemicalnature of all lanthanide ions our work sheds light on the formationstages of Ln:YLF NCs in general.

Abstract: The recent energy crisis revealed that there is a strong need to replace hydrocarbon-fueled industrial nitrogen fixation processes by alternative, more sustainable methods. In light of this, plasma-based nitrogen fixation remains one of the most promising options, considering both theoretical and experimental aspects. Lately, plasma interacting with water has received considerable attention in nitrogen fixation applications as it can trigger a unique gas- and liquid-phase chemistry. Within this context, a critical exploration of plasma-assisted nitrogen fixation with or without water presence is of great interest with an emphasis on energy costs, particularly in plasma reactors which have potential for large-scale industrial application. In this work, the presence of water in a multi-pin plasma system on nitrogen oxidation is experimentally investigated by comparing two pulsed negative DC voltage plasmas in metal–metal and metal–liquid electrode configurations. The plasma setups are designed to create similar plasma properties, including plasma power and discharge regime in both configurations. The system energy cost is calculated, considering nitrogen-containing species generated in gas and liquid phases as measured by a gas analyzer, nitrate sensor, and a colorimetry method. The energy cost profile as a function of specific energy input showed a strong dependency on the plasma operational frequency and the gas flow rate, as a result of different plasma operation regimes and initiated reverse processes. More importantly, the presence of the plasma/liquid interface increased the energy cost up to 14 ± 8%. Overall, the results showed that the presence of water in the reaction zone has a negative impact on the nitrogen fixation process.

Abstract: The potential of cold atmospheric plasma (CAP) in biomedical applications has received significant interest, due to its ability to generate reactive oxygen and nitrogen species (RONS). Upon exposure to living cells, CAP triggers alterations in various cellular components, such as the cell membrane. However, the permeation of RONS across nitrated and oxidized membranes remains understudied. To address this gap, we conducted molecular dynamics simulations, to investigate the permeation capabilities of RONS across modified cell membranes. This computational study investigated the translocation processes of less hydrophilic and hydrophilic RONS across the phospholipid bilayer (PLB), with various degrees of oxidation and nitration, and elucidated the impact of RONS on PLB permeability. The simulation results showed that less hydrophilic species, i.e., NO, NO2, N2O4, and O3, have a higher penetration ability through nitro-oxidized PLB compared to hydrophilic RONS, i.e., HNO3, s-cis-HONO, s-trans-HONO, H2O2, HO2, and OH. In particular, nitro-oxidation of PLB, induced by, e.g., cold atmospheric plasma, has minimal impact on the penetration of free energy barriers of less hydrophilic species, while it lowers these barriers for hydrophilic RONS, thereby enhancing their translocation across nitro-oxidized PLB. This research contributes to a better understanding of the translocation abilities of RONS in the field of plasma biomedical applications and highlights the need for further analysis of their role in intracellular signaling pathways.

Abstract: In this theoretical study, we assess the impact of a graphene capping layer on the resistivity of defective, extremely scaled interconnects. We investigate the effect of graphene capping on the electronic transport in ultrascaled interconnects, in the presence of grain boundary defects in the metal layer. We compare the results obtained using our quantum mechanical model to a simple parallel-conductor model and find that the parallel-conductor model does not capture the effect of the graphene cap correctly. At 0.5 nm metal thickness, the parallel-conductor model underestimates the conductivity by 3.0% to 4.0% for single-sided and double sided graphene capping, respectively.

Abstract: The addition of potassium thiocyanate (KSCN) to the FAPbBr3 structure and subsequent post-treatment of nanocrystals (NCs) lead to high quantum confinement, resulting in a photoluminescent quantum yield (PLQY) approaching unity and microsecond decay times. This synergistic approach demonstrated exceptional stability under humid conditions, retaining 70% of the PLQY for over a month, while the untreated NCs degrade within 24 h. Additionally, the devices incorporating the post-treated NCs displayed 1.5% external quantum efficiency (EQE), a 5-fold improvement over untreated devices. These results provide promising opportunities for the use of perovskites in moisture-stable optoelectronics.

Abstract: In recent years, quantum dots (QDs) have emerged as bright,color-tunablelight sources for various applications such as light-emitting devices,lasing, and bioimaging. One important next step to advance their applicabilityis to reduce particle-to-particle variations of the emission propertiesas well as fluctuations of a single QD's emission spectrum,also known as spectral diffusion (SD). Characterizing SD is typicallyinefficient as it requires time-consuming measurements at the single-particlelevel. Here, however, we demonstrate multiparticle spectroscopy (MPS)as a high-throughput method to acquire statistically relevant informationabout both fluctuations at the single-particle level and variationsat the level of a synthesis batch. In MPS, we simultaneously measureemission spectra of many (20-100) QDs with a high time resolution.We obtain statistics on single-particle emission line broadening fora batch of traditional CdSe-based core-shell QDs and a batchof the less toxic InP-based core-shell QDs. The CdSe-basedQDs show significantly narrower homogeneous line widths, less SD,and less inhomogeneous broadening than the InP-based QDs. The timescales of SD are longer in the InP-based QDs than in the CdSe-basedQDs. Based on the distributions and correlations in single-particleproperties, we discuss the possible origins of line-width broadeningof the two types of QDs. Our experiments pave the way to large-scale,high-throughput characterization of single-QD emission propertiesand will ultimately contribute to facilitating rational design offuture QD structures.

Abstract: Ab initio density functional theory (DFT) and DFT plus coherent potential approximation (DFT + CPA) are employed to reveal, respectively, the effect of in-plane strain and site-diagonal disorder on the electronic structure of cubic boron arsenide (BAs). It is demonstrated that tensile strain and static diagonal disorder both reduce the semiconducting one-particle band gap of BAs, and a V-shaped p-band electronic state emerges – enabling advanced valleytronics based on strained and disordered semiconducting bulk crystals. At biaxial tensile strains close to 15% the valence band lineshape relevant for optoelectronics is shown to coincide with one reported for GaAs at low energies. The role played by static disorder on the As sites is to promote p-type conductivity in the unstrained BAs bulk crystal, consistent with experimental observations. These findings illuminate the intricate and interdependent changes in crystal structure and lattice disorder on the electronic degrees of freedom of semiconductors and semimetals.

Abstract: This study presents new insights on the effect of (sub)micrometer particle sized materials in plasma-based CO2-
CH4 reforming by investigating the performance of SiO2 spheres (with/without supported metal) of varying
particle sizes. (Sub)micron particles synthesized through the St¨ober method were used instead of (sub)millimeter
particles employed in previous studies. Increasing particle size (from 120 nm to 2390 nm) was found to first
increase and then decrease conversion and energy yield, with optimal performance achieved using 740 nm 5 wt%
Ni loaded SiO2, which improved CO2 and CH4 conversion, and energy yield to 44%, 55%, and 0.271 mmol/kJ,
respectively, compared to 20%, 27%, and 0.116 mmol/kJ in an empty reactor at the same flow rate. This is the
first to achieve significant performance improvement in a fully packed reactor, highlighting the importance of
selecting a suitable particle size. The findings can offer guidance towards rational design of catalysts for plasmabased
reactions.

Abstract: Since the onset of pattern transfer technologies for chip manufacturing, various strategies have been developed to circumvent or overcome aspect ratio dependent etching (ARDE). These methods have, however, their own limitations in terms of etch non-idealities, throughput or costs. Moreover, they have mainly been optimized for individual in-device features and die-scale patterns, while occasionally ending up with poor patterning of metrology marks, affecting the alignment and overlay in lithography. Obtaining a better understanding of the underlying mechanisms of ARDE and how to mitigate them therefore remains a relevant challenge to date, for both marks and advanced nodes. In this work, we accordingly assessed the neutral transport mechanisms in ARDE by means of experiments and multiscale modeling for SiO₂etching with CHF₃/Ar and CF₄/Ar plasmas. The experiments revealed a local maximum in the etch rate for an aspect ratio around unity, i.e. the simultaneous occurrence of regular and inverse reactive ion etching lag for a given etch condition. We were able to reproduce this ARDE trend in the simulations without taking into account charging effects and the polymer layer thickness, suggesting shadowing and diffuse reflection of neutrals as the primary underlying mechanisms. Subsequently, we explored four methods with the simulations to regulate ARDE, by varying the incident plasma species fluxes, the amount of polymer deposition, the ion energy and angular distribution and the initial hardmask sidewall angle, for which the latter was found to be promising in particular. Although our study focusses on feature dimensions characteristic to metrology marks and back-end-of-the-line integration, the obtained insights have a broader relevance, e.g. to the patterning of advanced nodes. Additionally, this work supports the insight that physisorption may be more important in plasma etching at room temperature than originally thought, in line with other recent studies, a topic on which we recommend further research.

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.

Abstract: Topochemistry enables step-by-step conversions of solid-state materials often leading to metastable structures that retain initial structural motifs. Recent advances in this field revealed many examples where relatively bulky anionic constituents were actively involved in redox reactions during (de)intercalation processes. Such reactions are often accompanied by anion-anion bond formation, which heralds possibilities to design novel structure types disparate from known precursors, in a controlled manner. Here we present the multistep conversion of layered oxychalcogenides Sr(2)MnO(2)Cu(1.5)Ch(2) (Ch=S, Se) into Cu-deintercalated phases where antifluorite type [Cu(1.5)Ch(2)](2.5-) slabs collapsed into two-dimensional arrays of chalcogen dimers. The collapse of the chalcogenide layers on deintercalation led to various stacking types of Sr(2)MnO(2)Ch(2) slabs, which formed polychalcogenide structures unattainable by conventional high-temperature syntheses. Anion-redox topochemistry is demonstrated to be of interest not only for electrochemical applications but also as a means to design complex layered architectures. Low temperature chemical transformations of solids using high-energy intermediates have enabled the synthesis of a new series of layered oxide chalcogenide containing oxidised chalcogenide dimers promising a new range of solids.

Abstract: The control of Mott phase is intertwined with the spatial reorganization of the electronic states. Out-of-equilibrium driving forces typically lead to electronic patterns that are absent at equilibrium, whose nature is however often elusive. Here, we unveil a nanoscale pattern formation in the Ca2 RuO4 Mott insulator. We demonstrate how an applied electric field spatially reconstructs the insulating phase that, uniquely after switching off the electric field, exhibits nanoscale stripe domains. The stripe pattern has regions with inequivalent octahedral distortions that we directly observe through high-resolution scanning transmission electron
microscopy. The nanotexture depends on the orientation of the electric field, it is non-volatile and rewritable. We theoretically simulate the charge and orbital reconstruction induced by a quench dynamics of the applied electric field providing clear-cut mechanisms for the stripe phase formation. Our results open the path for the design of non-volatile electronics based on voltage-controlled nanometric phases.

Abstract: The nanoscale photothermal effect and the optofluidic convection around plasmonic nanoparticles drive the application of such nanoparticles in micro-environment. In this work, heat transfer and fluid flow around Au nanospheres and nanorods in water medium under continuous and pulsed wave laser irradiance was investigated using an FEM based numerical framework. Au nanospheres of a wide range of diameter: 40 nm = Diameter (D) = 180 nm and relatively large nanorods (diameter: 50 nm) with varying aspect ratio (1 = Aspect ratio (A) = 5) and orientation (0 degrees = ? = 90 degrees, ? = 0 degrees, 90 degrees) with respect to the incident EM radiation were investigated for continuous wave (CW) and pulsed wave laser. It was found that although nanorods can attain much higher temperature than nanospheres, orientation of a nanorod is an important factor to be carefully considered in applications. In micro-scale spherical and hemispherical confinements (diameter < 14.4 p.m), the convective velocity fields around nanoparticles is in the order of 10-9 m/s, with only a weak effect of the slip or no-slip boundary condition on the confining walls. Importantly, the size of the confinement has a strong effect leading to an order of magnitude stronger convection for 14.4 p.m (diameter) spherical confinement as compared to 3.6 p.m confinement. Additionally close proximity of the nanoparticles to the confining walls strongly reduces (by an order of magnitude) the convective currents. The results reported herein provides important insights for the use of photothermal nanoparticles in microscale confined space (e.g. cellular environment) for applications such as optical tweezers, photoporation, etc.