Assembly of highly efficient overall CO2 + H2O electrolysis cell with the matchup of CO2 reduction and water oxidation catalyst

Abstract

The exploitation of highly active and stable catalysts for reduction of CO₂ and water oxidation is one of the approaches to facilitate scalable and sustainable CO₂ reduction potentially at the industrial scale. Herein, a feasible strategy to rationally build an overall CO₂ + H₂O electrocatalytic reaction device is the preparation and matchup of a high-performance CO₂ reduction catalyst and low-cost and highly active oxygen anode catalyst. A heterostructured nanosheet, γ-NiOOH/NiCO₃/Ni(HCOO)₂, exhibited superior catalytic activity in the oxygen evolution reaction, and was integrated with CoPc/Fe–N–C to build an overall CO₂ + H₂O cell with a current density of 10 mA cm⁻² at a very low cell voltage of 1.97 V, and the faradaic deficiency of CO₂ to CO was maintained at greater than 90% at 1.9 V.