Preparation and performance of Cd-MgAl-LDHs@RGO in high efficiency electrocatalytic reduction of CO2 to CO

Abstract

As global carbon dioxide (CO2) emissions continuous increase, the greenhouse effect is becoming an inevitable problem and the conversion of CO2 into carbon-containing clean energy is a hot topic of research. In this paper, a kind of Cd-doped MgAl hydrotalcite composite electrocatalyst (Cd-MgAl-LDHs@RGO) grown in situ on reduced graphene oxide (RGO) was prepared by hydrothermal synthesis. The results show that Cd-MgAl-LDHs@RGO has excellent performance in CO2RR with multiple active sites, high selectivity and good stability. The structure of Cd-MgAl-LDHs@RGO can facilitate the adsorption and mass transfer of CO2 on the catalyst and has the relatively best electrochemical performance than the MgAl-LDHs and Cd-MgAl-LDHs. Its Faraday efficiency (CO FE) is up to 91.5% for the reduction of CO2 to carbon monoxide (CO) (-1.1 V vs. RHE), when the partial current density of CO is 3.39 mA·cm−2 and can be maintained for at least 7.5 h (-1.2 V vs. RHE). Therefore, the catalyst may be prospectively used for efficient electrocatalytic reduction of CO2 to CO, and also provides a promising strategy for the design of efficient electrocatalysts in the field of molecular catalysis.