Optimization Strategies for Selective CO₂ Electroreduction to Fuels

Abstract

Capturing CO₂ from the atmosphere and converting it into fuels are an efficient strategy to stop the deteriorating greenhouse effect and alleviate the energy crisis. Among various CO₂ conversion approaches, electrocatalytic CO₂ reduction reaction (CO₂RR) has received extensive attention because of its mild operating conditions. However, the high onset potential, low selectivity toward multi-carbon products and poor cruising ability of CO₂RR impede its development. To regulate product distribution, previous studies performed electrocatalyst modification using several universal methods, including composition manipulation, morphology control, surface modification, and defect engineering. Recent studies have revealed that the cathode and electrolytes influence the selectivity of CO₂RR via pH changes and ionic effects, or by directly participating in the reduction pathway as cocatalysts. This review summarizes the state-of-the-art optimization strategies to efficiently enhance CO₂RR selectivity from two main aspects, namely the cathode electrocatalyst and the electrolyte.

Keywords

CO₂ electroreduction / Fuel / Catalyst / Electrolyte / Selectivity

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