Efficient electrolysis of CO₂ capture solution to syngas over Ni‐N‐C catalyst

Abstract

Carbon dioxide (CO₂) electrolysis is an important process for storing excess renewable electricity. However, this process is commonly carried out in a high‐purity‐CO₂ environment. Here, we conduct a systematic investigation into the operational performance of CO₂ capture solutions for producing syngas. Using Ni‐N‐C electrocatalysts, by reducing the thickness of the catalytic layer and accelerating the mass transport, we achieve 58.6% CO Faradaic efficiency at a current density of 100 mA cm⁻² and a full cell voltage of 3.67 V. Efficient syngas (Mol_H2/Mol_CO = 1–4) production has achieved at a wide range of current densities, that is, 100 to 300 mA cm⁻² using a 3 M KHCO₃ solution. It is also demonstrated that the Ni‐N‐C electrocatalysts compared to commercial Ag catalysts show better impurity tolerance and CO selectivity. These findings underscore the potential of CO₂ capture solution as a direct carbon source for CO₂ electrolysis.