Surface ligand engineering on metal nanocatalysts for electrocatalytic CO2 reduction

Abstract

Electrocatalytic reduction of CO₂ into fuels and commodity chemicals has emerged as a potential way to balance the carbon cycle and produce reusable carbon fuels. However, the challenges of the competing reaction of hydrogen evolution reaction, low CO₂ concentration on the catalyst surface and the diversity of products significantly limit the catalytic activity and selectivity. Hereby, metal nanomaterials, protected by surface stabilizing ligands, have been widely studied in the field of CO₂ reduction due to their structural diversity and outstanding physical and chemical properties. Nevertheless, the surface organic ligands may lower the activity of electrocatalysts, while ligand detachment would cause original structure collapse and selectivity reduction. Therefore, the implementation of strategies based on designing nano-metal catalysts to promote CO₂ reduction from the perspective of metals and ligands has attracted increasing attention. Herein, we highlight the recent studies on the regulation of surface ligands of metal clusters and metal nanoparticles to promote CO₂ electroreduction. Meanwhile, we further summarize the relationship between the surface structure of metal nanocatalysts and the catalytic performance for CO₂ reduction reaction (CO₂RR). This mini review offers an inspiration in remaining challenges and future directions on nano-metal catalysts for electrocatalytic CO₂RR.