FUEL PROCESSING TECHNOLOGY
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2022
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IF 8.129
Dewang Zeng,Chen Wang,Tong Liu,Wentao Ou,Rui Xiao
Chemical looping methane oxidative coupling is a promising method to directly convert methane to C 2 products but is limited by the trade-off between CH 4 conversion and C 2 selectivity. Here, we develop a series of TiO 2 doped Na 2 WO 4 /Mn 2 O 3 /SiO 2 for chemical looping methane oxidative coupling and investigate the underline mechanism for the enhanced performance. The results show that 5 wt% TiO 2 doped Na 2 WO 4 /Mn 2 O 3 /SiO 2 exhibited 31.2% CH 4 conversion, which is 1.68 times as large as that of Na 2 WO 4 /Mn 2 O 3 /SiO 2 , without significantly decreasing C 2 selectivity (~70.3%). Pulse experiments show that TiO 2 improves the bulk oxygen diffusion, providing more surface oxygen to convert methane, thus leading to enhanced CH 4 conversion. O 1 s spectra manifests that the active oxygen content on the surface was not significantly increased by TiO 2 dopant , thus TiO 2 dopant has little effect on C 2 selectivity. Therefore, 5 wt% TiO 2 doped Na 2 WO 4 /Mn 2 O 3 /SiO 2 shows high chemical looping methane oxidative coupling performance. The explored mechanism in this work can be extended to design more oxygen carriers to enhance the chemical looping reactions.
研究领域:
化学工程
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
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2025
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IF 9.7
Junming Zhang,Xianchen Xu,Xin Guo,Na Liu,Xiongfeng Ma,Hongwei Ren,He Xiao,Man Zhao,Baoliang Lv,Jingxiao Tang,Tianjun Hu,Jianfeng Jia
Against the backdrop of global carbon neutrality target driving the transformation of energy structure, alcohol fuel cells (AFCs) show great application potential; However, the sluggish kinetics of their anodic alcohol oxidation reaction hinders the commercialization of AFCs. Metallene is a novel 2D material with potential application prospect in the field of electrocatalysis. In this paper, Pd 1 Mo 1 W trimetallene has been successfully produced by a one-pot wet-chemical method, which displays a unique two-dimensional curved ultrathin graphene structure. Mo and W atoms were doped into the lattice of Pd atoms to form a Pd 1 Mo 1 W ternary alloy, which resulted in the lattice spacing of Pd being enlarged to 0.229 nm and the d-band center of Pd being reduced by 1.10 eV. Therefore, Pd 1 Mo 1 W trimetallene demonstrated excellent electrocatalytic performance for the oxidation of ethanol and ethylene glycol in alkaline electrolyte. Especially for the ethanol oxidation reaction (EOR), Pd 1 Mo 1 W trimetallene exhibited excellent mass activity (7.55 A mg Pd −1 ) and intrinsic activity (13.5 mA cm −2 ), low apparent activation energy (41.8 kJ mol −1 ), and outstanding CO anti-poisoning ability. According to the nuclear magnetic resonance, in-situ fourier transform infrared reflection spectra, and density-functional theory calculations, it is revealed that the Pd 1 Mo 1 W trimetallene with high surface area formed by Mo-doping reduces the d-band center of the active site, facilitates the adsorption of OH species, and enhances the tolerance of CO-poisoned intermediate, so that EOR can be carried out through C1 and C2 pathways at a lower potential. Compared to the electrocatalytic EOR system, the photocurrent density of Pd 1 Mo 1 W trimetallene under xenon lamp irradiation increased by 1.73 times, which was mainly attributed to the electron resonance effect generated by Mo and W elements to promote the electron transfer to Pd. The excellent electrocatalytic ethanol and ethylene glycol performance of Pd 1 Mo 1 W demonstrates the great application potential of metallene for electrocatalysis.
研究领域:
电化学
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催化
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材料科学
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纳米技术
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能量转换
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表面科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
APPLIED CATALYSIS B-ENVIRONMENTAL
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2025
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IF 21.1
Tinghui An,Nan Wang,Jiaqi Li,Yuhao Wang,Zongxuan Bai,Dong Xiang,Kedi Cai
Cu-based electrocatalysts possesses superior potential to produce energy-dense fuels and value-added chemicals in electrocatalytic CO 2 reduction reaction (eCO 2 RR). Nevertheless, the desperately desired target C 2 selectivity is fundamentally constrained by inevitable hydrogen evolution reaction (HER), C 1 products competition and sluggish reaction kinetics, especially for ethanol. Herein, the strategy of introducing Mg on CuO is proposed to aim at modulating adsorption energetics of oxygen-associated active species, which can effectively suppress competing pathways while boosting ethanol production. Benefitting from the modified electronic structure and lattice compressive strain induced by Mg-doping, Mg 0.34 @CuO exhibited 77.5 % of C 2 FE with remarkable stability, in which FE C2H5OH could reach 48.5 % with total current density of 245.5 mA cm −2 . Density functional theory (DFT) calculation revealed that Mg-doped Cu surface exhibits multiple catalytic function, such as suppressed HER, increased surface CO coverage and accelerated H 2 O dissociation, which can be conducive to promote ethanol production. Incorporation of Mg significantly reduces the energy barrier for asymmetric CO-CHO coupling reaction and stabilizes C-O bond in *CH 2 CHO intermediate (shared by ethylene (C 2 H 4 ) and ethanol (C 2 H 5 OH)) by enhancing d-p orbital coupling, thus prioritizing C 2 H 5 OH pathway. Furthermore, it could achieve a high discharge capacity of 14944 mAh g −1 and stable charge-discharge operation of 153 cycles in Li-CO 2 batteries that utilize Mg 0.34 @CuO as cathode material. This work demonstrates a generalizable approach to regulate eCO 2 RR activity and selectivity, and meanwhile shows great application potential in rechargeable Li-CO 2 batteries.
研究领域:
电化学
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能量转换
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材料科学
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催化
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环境科学
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理论化学
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）