Decoration of Ag nanoparticles on CoMoO 4 rods for efficient electrochemical reduction of CO 2

Hydrothermal and photoreduction/deposition methods were used to fabricate Ag nanoparticles (NPs) decorated CoMoO rods. Improvement of charge transfer and transportation of ions by making heterostructure was proved by cyclic voltammetry and electrochemical impedance spectroscopy measurements. Linear sweep voltammetry results revealed a fivefold enhancement of current density by fabricating heterostructure. The lowest Tafel slope (112 mV/dec) for heterostructure compared with CoMoO (273 mV/dec) suggested the improvement of electrocatalytic performance. The electrochemical CO reduction reaction was performed on an H-type cell. The CoMoO electrocatalyst possessed the Faraday efficiencies (FEs) of CO and CH up to 56.80% and 19.80%, respectively at - 1.3 V versus RHE. In addition, Ag NPs decorated CoMoO electrocatalyst showed FEs for CO, CH , and C H were 35.30%, 11.40%, and 44.20%, respectively, at the same potential. It is found that CO reduction products shifted from CO/CH to C H when the Ag NPs deposited on the CoMoO electrocatalyst. In addition, it demonstrated excellent electrocatalytic stability after a prolonged 25 h amperometric test at - 1.3 V versus RHE. It can be attributed to a synergistic effect between the Ag NPs and CoMoO rods. This study highlights the cooperation between Ag NPs on CoMoO components and provides new insight into the design of heterostructure as an efficient, stable catalyst towards electrocatalytic reduction of CO to CO, CH , and C H products.