Electrochemical reduction of SnO2 to Sn from the Bottom: In-Situ formation of SnO2/Sn heterostructure for highly efficient electrochemical reduction of carbon dioxide to formate

• Published in: Journal of catalysis Vol. 399; pp. 67 - 74
• Main Authors: Ning, Shunlian, Wang, Jigang, Xiang, Dong, Huang, Shaobin, Chen, Wei, Chen, Shaowei, Kang, Xiongwu
• Format: Journal Article
• Language: English
• Published: Elsevier Inc 01.07.2021
• Subjects: carbon; carbon dioxide; catalysts; catalytic activity; density functional theory; DFT calculations; electrochemical CO2 reduction; electrochemistry; electrodes; electrolysis; energy; Formate; formates; hydrogen; In-situ reconstruction; operando Raman spectroscopy; Raman spectroscopy; SnO2/Sn heterostructures; value added; X-ray diffraction; X-ray photoelectron spectroscopy; SnO2/Sn heterostructures; Formate; electrochemical CO2 reduction; In-situ reconstruction; operando Raman spectroscopy; DFT calculations
• ISSN: 0021-9517; 1090-2694
• DOI: 10.1016/j.jcat.2021.04.028

[Display omitted] •Top/bottom heterostructured SnO2/Sn was formed during electrocatalysis CO2 reduction.•The sample was examined by operando Raman and X-ray photoelectron spectroscopy.•The SnO2/Sn delivers a FE of 94% for formate and current density of 113.6 mA cm−2 at − 1.18 V.•DFT calculations show that formate was more favored on SnO2/Sn than SnO2 and Sn. Design and engineering of low-cost, high-performance catalysts is a critical step in electrochemical CO2 reduction (CO2R) to value-added chemicals and fuels. Herein, SnO2 nanoparticles were grown onto carbon cloth (SnO2/CF) by a facile hydrothermal procedure and exhibited excellent electrocatalytic activity towards CO2R due to reconstruction into SnO2/Sn Mott-Schottky heterojunctions during CO2R electrolysis, as manifested in X-ray diffraction, X-ray photoelectron spectroscopy, and operando Raman spectroscopy measurements. The heterostructured SnO2/Sn electrode delivered a high faradaic efficiency of 93 ± 1% and a partial current density of 28.7 mA cm−2 for formate production at − 1.0 V vs. reversible hydrogen electrode in an H-type cell (which remained stable for 9 h), and 174.86 mA cm−2 at − 1.18 V on a gas-diffusion electrode in a flow cell. Density functional theory calculations show that the SnO2/Sn heterostructures in situ formed under CO2R conditions helped decrease the energy barrier to form formate as compared to pristine SnO2 and Sn, and were responsible for the high activity and selectivity of formate production. Results from this study unravels the evolution dynamics of SnO2 catalysts under CO2R condition and provides a further understanding of the active component of SnO2 catalyst in CO2R.