Efficient electrochemical reduction of CO2 into CO promoted by sulfur vacancies

By Binhao Qin, Yuhang Li, Hongjuan Wang, Guangxing Yang, Yong Cao, Hao Yu, Qiao Zhang, Hong Liang, F. Peng. Nano Energy, 2019

160 citations recorded by the source corpus.

Abstract Electrochemical conversion of carbon dioxide (CO2) into useful chemicals has attracted a lot of attention to store energy and reduce the greenhouse effect. Herein, a new electrocatalyst of carbon nanotubes coated with cadmium sulfide is reported, the faradaic efficiency (FE) of CO2 reduction reaction (CO2RR) to carbon monoxide (CO) is as high as 95%. We clearly demonstrate that sulfur vacancies (S-vacancies) are in-situ generated on the catalyst surface in CO2RR, which is evidenced by electron paramagnetic resonance spectra (EPR), in-situ differential electrochemical mass spectrometry (DEMS) and inductively-coupled plasma spectrometer (ICP). With the increase of S-vacancies, the catalytic activity of CO2RR to CO improve significantly and the charge-transfer resistance decrease. Combined with in-situ infrared absorption spectroscopy and density functional theory calculations, it can be concluded that the formation of S-vacancies changes the electron density of the catalyst surface and decreases the energy barrier for the conversion of COOH∗ to CO∗. Finally, we tried to power electrochemical reduction of CO2 with solar panel under natural light conditions, the energy conversion efficiency on CdS-CNT catalyst from solar energy to CO has been calculated, predicting a hopeful application prospect in the future.

Subfields: Catalysis, Materials Chemistry, Renewable Energy, Sustainability and the Environment

View Paper: https://www.semanticscholar.org/paper/b17a9c9360792199e828fe3c0d5fce3d84f3fdb0