The use of gas diffusion electrode(GDE)based flow cell can realize industrial-scale CO_(2) reduction reactions(CO_(2)RRs).Controlling local CO_(2) and CO intermediate diffusion plays a key role in CO_(2)RR toward mult...The use of gas diffusion electrode(GDE)based flow cell can realize industrial-scale CO_(2) reduction reactions(CO_(2)RRs).Controlling local CO_(2) and CO intermediate diffusion plays a key role in CO_(2)RR toward multi-carbon(C_(2+))products.In this work,local CO_(2) and CO intermediate diffusion through the catalyst layer(CL)was investigated for improving CO_(2)RR toward C_(2+)products.The gas permeability tests and finite element simulation results indicated CL can balance the CO_(2) gas diffusion and residence time of the CO intermediate,leading to a sufficient CO concentration with a suitable CO_(2)/H_(2)O supply for high C_(2+)products.As a result,an excellent selectivity of C_(2+)products~79%at a high current density of 400 mA·cm^(-2) could be obtained on the optimal 500 nm Cu CL(Cu500).This work provides a new insight into the optimization of CO_(2)/H_(2)O supply and local CO concentration by controlling CL for C_(2+)products in CO_(2)RR flow cell.展开更多
The large-scale production of ammonia mainly depends on the Haber-Bosch process,which will lead to the problems of high energy consumption and carbon dioxide emission.Electrochemical nitrogen fixation is considered to...The large-scale production of ammonia mainly depends on the Haber-Bosch process,which will lead to the problems of high energy consumption and carbon dioxide emission.Electrochemical nitrogen fixation is considered to be an environmental friendly and sustainable process,but its efficiency largely depends on the activity and stability of the catalyst.Therefore,it is imperative to develop high-efficient electrocatalysts in the field of nitrogen reduction reaction(NRR).In this paper,we developed a BiVO_(4)/TiO_(2) nanotube(BiVO_(4)/TNT)heterojunction composite with rich oxygen vacancies as an electrocatalytic NRR catalyst.The heterojunction interface and oxygen vacancy of BiVO_(4)/TNT can be the active site of N2 dynamic activation and proton transition.The synergistic effect of TiO_(2) and BiVO_(4) shortens the proton transport path and reduces the over potential of chemical reaction.BiVO_(4)/TNT has high ammonia yield of 8.54µg·h^(−1)·cm^(−2) and high Faraday efficiency of 7.70%in−0.8 V vs.RHE in 0.1 M Na_(2)SO_(4) solution.展开更多
基金The authors gratefully thank the National Natural Science Foundation of China(No.22002189)Central South University Research Programme of Advanced Interdisciplinary Studies(No.2023QYJC012)+1 种基金Central South University Innovation-Driven Research Program(No.2023CXQD042)the Fundamental Research Funds for the Central Universities of Central South University(No.2023ZZTS0962).
文摘The use of gas diffusion electrode(GDE)based flow cell can realize industrial-scale CO_(2) reduction reactions(CO_(2)RRs).Controlling local CO_(2) and CO intermediate diffusion plays a key role in CO_(2)RR toward multi-carbon(C_(2+))products.In this work,local CO_(2) and CO intermediate diffusion through the catalyst layer(CL)was investigated for improving CO_(2)RR toward C_(2+)products.The gas permeability tests and finite element simulation results indicated CL can balance the CO_(2) gas diffusion and residence time of the CO intermediate,leading to a sufficient CO concentration with a suitable CO_(2)/H_(2)O supply for high C_(2+)products.As a result,an excellent selectivity of C_(2+)products~79%at a high current density of 400 mA·cm^(-2) could be obtained on the optimal 500 nm Cu CL(Cu500).This work provides a new insight into the optimization of CO_(2)/H_(2)O supply and local CO concentration by controlling CL for C_(2+)products in CO_(2)RR flow cell.
基金This work was supported by the National Natural Science Foundation of China(Grant Nos.51802126 and 52072152)the Jiangsu University Jinshan Professor Fund and Jiangsu Specially-Appointed Professor Fund,Open Fund from Guangxi Key Laboratory of Electrochemical Energy Materials+1 种基金The authors also acknowledged the financial support by Guangdong Innovation Research Team for Higher Education(No.2017KCXTD030)High-level Talents Project of Dongguan University of Technology(No.KCYKYQD2017017).
文摘The large-scale production of ammonia mainly depends on the Haber-Bosch process,which will lead to the problems of high energy consumption and carbon dioxide emission.Electrochemical nitrogen fixation is considered to be an environmental friendly and sustainable process,but its efficiency largely depends on the activity and stability of the catalyst.Therefore,it is imperative to develop high-efficient electrocatalysts in the field of nitrogen reduction reaction(NRR).In this paper,we developed a BiVO_(4)/TiO_(2) nanotube(BiVO_(4)/TNT)heterojunction composite with rich oxygen vacancies as an electrocatalytic NRR catalyst.The heterojunction interface and oxygen vacancy of BiVO_(4)/TNT can be the active site of N2 dynamic activation and proton transition.The synergistic effect of TiO_(2) and BiVO_(4) shortens the proton transport path and reduces the over potential of chemical reaction.BiVO_(4)/TNT has high ammonia yield of 8.54µg·h^(−1)·cm^(−2) and high Faraday efficiency of 7.70%in−0.8 V vs.RHE in 0.1 M Na_(2)SO_(4) solution.