In-situ-derived self-selective electrocatalysts for solar formate production from simultaneous CO2 reduction and methanol oxidation
Zaiqi Li, Yugang Gao, Xiao Meng, Bin Sun, Kepeng Song, Zeyan Wang, Yuanyuan Liu, Zhaoke Zheng, Peng Wang, Ying Dai, Hefeng Cheng, Baibiao Huang
Abstract
Solar-driven electrochemical CO2 reduction reaction (CO2RR) offers a promising route to achieve a carbon-neutral and energy-sustainable future. However, the anodic oxygen evolution reaction (OER) hinders the energy input utilization, and the added value of the product O2 is low. Here, through a combined CO2RR and selective methanol oxidation reaction (MOR), we report an efficient and unassisted solar-driven simultaneous cathodic and anodic production of formate on hydroxide-derived self-selective Cu-based electrocatalysts. Upon in situ treatments, Cu(OH)2-derived Cu (HOD-Cu) and CuO (HOD-CuO) electrocatalysts display efficient CO2RR and MOR performances at a wide potential range, respectively. The rational integration of the electrolyzer to a triple junction GaInP/GaAs/Ge photovoltaic cell could realize efficient solar-driven formate synthesis, leading to a solar-to-formate (STF) conversion efficiency of 3.63% and a production rate of 0.194 mmol h−1 cm−2. This work demonstrates a simultaneous formate generation by coupling CO2RR and MOR, providing new paths for solar-driven electrochemical synthesis.