A novel catalyst for CO2 electroreduction based on nanostructured SnO2 was synthesized using a facile hydrothermal self-assembly method. The electrochemical activity showed that the catalyst gave outstanding catalytic...A novel catalyst for CO2 electroreduction based on nanostructured SnO2 was synthesized using a facile hydrothermal self-assembly method. The electrochemical activity showed that the catalyst gave outstanding catalytic activity and selectivity in CO2 electroreduction. The catalytic activity and formate selectivity depended strongly on the electrolyte conditions. A high faradaic efficiency, i.e., 56%, was achieved for formate formation in KHCO3 （0.5 mol/L）. This is attributed to control of formate production by mass and charge transfer processes. Electrolysis experiments using SnO2-50/GDE （an SnOz-based gas-diffusion electrode, where 50 indicates the 50% ethanol content of the electrolyte） as the catalyst, showed that the electrolyte pH also affected CO2 reduction. The optimum electrolyte pH for obtaining a high faradaic efficiency for formate production was 8.3. This is mainly because a neutral or mildly alkaline environment maintains the oxide stability. The fara- daic efficiency for formate production declined with time. X-ray photoelectron spectroscopy showed that this is the result of deposition of trace amounts of fluoride ions on the SnO2-50/GDE surface, which hinders reduction of CO2 to formate.展开更多
基金supported by the Innovation Program of the Shanghai Municipal Education Commission(14ZZ074)the International Academic Coop-eration and Exchange Program of Shanghai Science and Technology Committee(14520721900)+1 种基金Graduate Innovation Fund of Donghua University(15D311304)the College of Environmental Science and Engineering,State Environmental Protection Engineering Center for Pollution Treatment and Control in Textile Industry,Donghua University.All the financial supports are gratefully acknowledged~~
文摘A novel catalyst for CO2 electroreduction based on nanostructured SnO2 was synthesized using a facile hydrothermal self-assembly method. The electrochemical activity showed that the catalyst gave outstanding catalytic activity and selectivity in CO2 electroreduction. The catalytic activity and formate selectivity depended strongly on the electrolyte conditions. A high faradaic efficiency, i.e., 56%, was achieved for formate formation in KHCO3 （0.5 mol/L）. This is attributed to control of formate production by mass and charge transfer processes. Electrolysis experiments using SnO2-50/GDE （an SnOz-based gas-diffusion electrode, where 50 indicates the 50% ethanol content of the electrolyte） as the catalyst, showed that the electrolyte pH also affected CO2 reduction. The optimum electrolyte pH for obtaining a high faradaic efficiency for formate production was 8.3. This is mainly because a neutral or mildly alkaline environment maintains the oxide stability. The fara- daic efficiency for formate production declined with time. X-ray photoelectron spectroscopy showed that this is the result of deposition of trace amounts of fluoride ions on the SnO2-50/GDE surface, which hinders reduction of CO2 to formate.
