Wang, Linlin; Li, Xin; Hao, Leiduan; Hong, Song; Robertson, Alex W.; Sun, Zhenyu

CHINESE JOURNAL OF CATALYSIS

2022, 43, 0253-9837

Wang, Linlin; Li, Xin; Hao, Leiduan; Hong, Song; Robertson, Alex W.; Sun, Zhenyu

To facilitate the electrochemical CO2 reduction (ECR) to fuels and valuable chemicals, the development of active, low cost, and selective catalysts is crucial. We report a novel ECR catalyst consisting of CuO nanoparticles with sizes ranging from 1.4 to 3.3 nm anchored on Cu metal-organic framework (Cu-MOF) nanosheets obtained through a one-step facile solvothermal method. The nanocomposites provide multiple sites for efficient ambient ECR, delivering an average C2H4 faradaic efficiency (FE) of similar to 50.0% at -1.1 V (referred to the reversible hydrogen electrode) in 0.1 mol/L aqueous KHCO3 using a two-compartment cell, in stark contrast to a C2H4 FE of 25.5% and 37.6% over individual CuO and Cu-MOF respectively, also surpassing most newly reported Cu-based materials under similar cathodic voltages. The C2H4 FE remains at over 45.0% even after 10.0 h of successive polarization. Also, a similar to 7.0 mA cm(-2) C2H4 partial geometric current density and 27.7% half-cell C2H4 power conversion efficiency are achieved. The good electrocatalytic performance can be attributed to the interface between CuO and Cu-MOF, with accessible metallic moieties and the unique two-dimensional structure of the Cu-MOF enhancing the adsorption and activation of CO2 molecules. This finding offers a simple avenue to upgrading CO2 to value-added hydrocarbons by rational design of MOF-based composites. (C) 2022, Dalian Institute of Chemical Physics, Chinese Academy of Sciences. Published by Elsevier B.V. All rights reserved.