Recent advances in surface modification for enhanced electrocatalytic CO2 reduction

Abstract

The electrochemical CO₂ reduction reaction (CO₂RR) provides a sustainable route for recycling CO₂ and producing value-added chemical feedstocks. However, there are some challenges in this field such as low reaction rate, poor product selectivity (faradaic efficiency), and insufficient stability. Recently, catalytic surface modification has emerged as an effective way to enhance the electrocatalytic CO₂ reduction performance, which plays multiple roles in the CO₂RR, i.e., increasing local CO₂ concentration, regulating the electronic structure of the catalyst, stabilizing key intermediates, inhibiting the side reaction of the hydrogen evolution reaction (HER), etc. Herein, we comprehensively summarized for the first time the recent advances in the electrocatalytic CO₂ reduction reaction using various catalytic surface modification strategies, including conductive polymer modification, hydrophobic polymer modification, surfactant modification, ionic liquid and poly(ionic liquid) modification, as well as small organic molecule modification. We highlighted the changes in the surface properties and CO₂RR performance of heterogeneous catalysts after surface modification and discussed the underlying mechanisms. Finally, the critical challenges and future opportunities in this field were indicated. This review is expected to provide valuable guidance for the rational design of electrocatalysts with satisfactory activity, selectivity, and durability toward target products.