Electrocatalytic CO2reduction is an effective way to close the global carbon cycle. Tin oxides have been demonstrated as promising catalysts to convert CO2into formate with high selectivity but with low reactivity and within a narrow potential window. Herein, octahedral tin oxide (SnO2) single crystals have been well tuned and exhibited a high formate selectivity within a 500 mV wide operation range and a remarkable high formate partial current density of ∼500 mA cm−2.In situRaman spectroscopy and DFT calculations indicate that high-energy facets of SnO2favor the adsorption of *OCHO and the desorption of HCOOH*, which breaks the limitation of the scaling relationship of these intermediates on the (110) facet of conventional SnO2nanoparticles and thus enhances formate selectivity. More interestingly, a maximum formate selectivity of 95% is achieved on SnO2(111) due to the deeply suppressed hydrogen evolution in seawater. These catalysts have been further coupled with chlor-alkali electrolyzers to convert greenhouse gas CO2into formate and produce higher-value Cl2simultaneously. The present work will advance the development of practical CO2electrolyzers.
Bibliographical noteFunding Information:
The authors are grateful for the nancial support from the National Nature Science Foundation of China (Grant No. 21938008 and 22078232) and the Science and Technology Major Project of Tianjin (Grant No. 18ZXJMTG00180 and 19ZXNCGX00030). Y. Su acknowledges the “Young Talent Support Plan” of Xi'an Jiaotong University and the supercomputing facilities supported by the HPC Platform, Xi'an Jiaotong University.
© The Royal Society of Chemistry 2021.
Copyright 2021 Elsevier B.V., All rights reserved.