Two-Dimensional SnO<sub>2</sub> Nanosheets for Efficient Carbon Dioxide Electroreduction to Formate
Jing Li, Jiqing Jiao, Haochen Zhang, Peng Zhu, Hefeng Ma, Chen Chen, Hai Xiao, Qi Lu
Abstract
The electrocatalytic reduction of CO2 to liquid fuels is a promising strategy to store the intermittent renewable energies into high-value chemicals. Here, two-dimensional SnO2 nanosheet (∼3 nm in thickness) materials were synthesized using the hydrothermal method and characterized as efficient electrocatalysts for CO2 reduction to formate. Compared to the monometallic Sn-based catalysts, the SnO2 nanosheet electrodes exhibit a much improved performance. A large current density of 471 mA cm–2 for formate production and a high Faradaic efficiency of 94.2% are simultaneously achieved using a three-compartment microfluidic flow cell electrolyzer. These results set a new record for formate production among monometallic Sn-based catalysts for the CO2 electroreduction reaction. Density functional theory calculations reveal the intrinsic improvement in the performance by the SnO2 surface site over the metallic Sn site.