Zeolitic imidazolate framework-derived composites with SnO2 and ZnO phase components for electrocatalytic carbon dioxide reduction.

Zeolitic imidazolate framework (ZIF) and its derivatives have attracted a great deal of attention in the field of electrocatalysis. In this paper, a series of tin (Sn)-modified ZIF-based composites (ZSO-X/Y) are synthesized and used as catalysts for the electrochemical reduction of CO2 to produce low-carbon fuels. Among the catalysts obtained, ZSO-2/8 shows the best formate (HCOO-) selectivity compared with others. A faradaic efficiency of 76.70% and a catalytic current density of -9.81 mA cm-2 can be respectively achieved at a potential of -1.16 V vs. reversible hydrogen electrode (VRHE). The high catalytic performance can be attributed to the stable coexistence of two-phase components of SnO2/ZnO inside the catalyst. This work provides an insight into the development of high performance ZIF-based catalysts for the electrochemical reduction of CO2.