Records |
Author |
Yi, Y.; Wang, X.; Jafarzadeh, A.; Wang, L.; Liu, P.; He, B.; Yan, J.; Zhang, R.; Zhang, H.; Liu, X.; Guo, H.; Neyts, E.C.; Bogaerts, A. |
Title |
Plasma-Catalytic Ammonia Reforming of Methane over Cu-Based Catalysts for the Production of HCN and H2at Reduced Temperature |
Type |
A1 Journal article |
Year ![sorted by Year field, ascending order (up)](img/sort_asc.gif) |
2021 |
Publication |
Acs Catalysis |
Abbreviated Journal |
Acs Catal |
Volume |
11 |
Issue |
3 |
Pages |
1765-1773 |
Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
Abstract |
Industrial production of HCN from NH3 and CH4 not only uses precious Pt or Pt−Rh catalysts but also requires extremely high temperatures (∼1600 K). From an energetic, operational, and safety perspective, a drastic decrease in temperature is highly desirable. Here, we report ammonia reforming of methane for the production of HCN and H2 at 673 K by the combination of CH4/NH3 plasma and a supported Cu/silicalite-1 catalyst. 30% CH4 conversion has been achieved with 79% HCN selectivity. Catalyst characterization and plasma diagnostics reveal that the excellent reaction performance is attributed to metallic Cu active sites. In addition, we propose a possible reaction pathway, viz. E-R reactions with N, NH, NH2, and CH radicals produced in the plasma, for the production of HCN, based on density functional theory calculations. Importantly, the Cu/silicalite-1 catalyst costs less than 5% of the commercial Pt mesh catalyst. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000618540300057 |
Publication Date |
2021-02-05 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2155-5435 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
10.614 |
Times cited |
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Open Access |
OpenAccess |
Notes |
Universiteit Antwerpen, 32249 ; China Postdoctoral Science Foundation, 2015M580220 2016T90217 ; PetroChina Innovation Foundation, 2018D-5007-0501 ; National Natural Science Foundation of China, 21503032 ; We acknowledge financial support from the National Natural Science Foundation of China [21503032], the China Postdoctoral Science Foundation [grant numbers 2015M580220 and 2016T90217, 2016], the PetroChina Innovation Foundation [2018D-5007-0501], and the TOP research project of the Research Fund of the University of Antwerp [grant ID 32249]. |
Approved |
Most recent IF: 10.614 |
Call Number |
PLASMANT @ plasmant @c:irua:175880 |
Serial |
6675 |
Permanent link to this record |
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Author |
Xiao, H.; Zhang, Z.; Xu, W.; Wang, Q.; Xiao, Y.; Ding, L.; Huang, J.; Li, H.; He, B.; Peeters, F.M. |
Title |
Terahertz optoelectronic properties of synthetic single crystal diamond |
Type |
A1 Journal article |
Year ![sorted by Year field, ascending order (up)](img/sort_asc.gif) |
2023 |
Publication |
Diamond and related materials |
Abbreviated Journal |
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Volume |
139 |
Issue |
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Pages |
110266-110268 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
A systematic investigation is undertaken for studying the optoelectronic properties of single crystal diamond (SCD) grown by microwave plasma chemical vapor deposition (MPCVD). It is indicated that, without intentional doping and surface treatment during the sample growth, the terahertz (THz) optical conduction in SCD is mainly affected by surface H-terminations, -OH-, O- and N-based functional groups. By using THz time-domain spectroscopy (TDS), we measure the transmittance, the complex dielectric constant and optical conductivity σ(ω) of SCD. We find that SCD does not show typical semiconductor characteristics in THz regime, where σ(ω) cannot be described rightly by the conventional Drude formula. Via fitting the real and imaginary parts of σ(ω) to the Drude-Smith formula, the ratio of the average carrier density to the effective electron mass γ = ne/m*, the electronic relaxation time τ and the electronic backscattering or localization factor can be determined optically. The temperature dependence of these parameters is examined. From the temperature dependence of γ, a metallic to semiconductor transition is observed at about T = 10 K. The temperature dependence of τ is mainly induced by electron coupling with acoustic-phonons and there is a significant effect of photon-induced electron backscattering or localization in SCD. This work demonstrates that THz TDS is a powerful technique in studying SCD which contains H-, N- and O-based bonds and has low electron density and high dc resistivity. The results obtained from this study can benefit us to gain an in-depth understanding of SCD and may provide new guidance for the application of SCD as electronic, optical and optoelectronic materials. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
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Publication Date |
2023-08-02 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0925-9635 |
ISBN |
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Additional Links |
UA library record |
Impact Factor |
4.1 |
Times cited |
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Open Access |
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Notes |
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Approved |
Most recent IF: 4.1; 2023 IF: 2.561 |
Call Number |
UA @ admin @ c:irua:200920 |
Serial |
9103 |
Permanent link to this record |
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Author |
Xiao, H.; Wen, H.; Xu, W.; Cheng, Y.; Zhang, J.; Cheng, X.; Xiao, Y.; Ding, L.; Li, H.; He, B.; Peeters, F.M. |
Title |
Terahertz magneto-optical properties of Nitrogen-doped diamond |
Type |
A1 Journal article |
Year ![sorted by Year field, ascending order (up)](img/sort_asc.gif) |
2024 |
Publication |
Infrared physics and technology |
Abbreviated Journal |
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Volume |
138 |
Issue |
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Pages |
105237-105239 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Nitrogen-doped diamond (N-D) is one of the most important carbon-based electronic and optical materials. Here we study the terahertz (THz) magneto-optical (MO) properties of N-D grown by microwave plasma-enhanced chemical vapor deposition. The optical microscope, SEM, XRD, Raman spectrum, FTIR spectroscopy and XPS are used for the characterization of N-D samples. Applying THz time-domain spectroscopy (TDS), in combination with the polarization test and the presence of magnetic field in Faraday geometry, THz MO transmissions through N-D are measured from 0 to 8 T at 80 K. The complex right- and left-handed circular transmission coefficients and MO conductivities for N-D are obtained accordingly. Through fitting the experimental results with theoretical formulas of the dielectric constant and MO conductivities for an electron gas, we are able to determine magneto-optically the key electronic parameters of N-D, such as the static dielectric constant epsilon b, the electron density ne, the electronic relaxation time tau, the electronic localization factor alpha and, particularly, the effective electron mass m* obtained under non-resonant condition. The dependence of these parameters upon magnetic field is examined and analyzed. We find that the MO conductivities of N-D can be described rightly by the MO Drude-Smith formulas developed by us previously. It is shown that N-doping and the presence of the magnetic field can lead towards the larger epsilon b and heavier m* in diamond, while ne/tau/alpha in N-D decreases/increases/decreases with increasing magnetic field. The results obtained from this work are benefit to us in gaining an in-depth understanding of the electronic and optoelectronic properties of N-D. |
Address |
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Corporate Author |
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Thesis |
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Place of Publication |
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Language |
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Wos |
001200173100001 |
Publication Date |
2024-02-15 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1350-4495 |
ISBN |
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Additional Links |
UA library record; WoS full record |
Impact Factor |
3.3 |
Times cited |
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Open Access |
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Notes |
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Approved |
Most recent IF: 3.3; 2024 IF: 1.713 |
Call Number |
UA @ admin @ c:irua:205523 |
Serial |
9178 |
Permanent link to this record |