Unravelling the Effect of Activators used in The Synthesis of Biomass-Derived Carbon Electrocatalysts on the Electrocatalytic Performance for CO2 Reduction

Abstract

N-doped carbon materials can be efficient and cost-effective catalysts for the electrochemical CO₂ reduction reaction (CO₂ RR). Activators are often used in the synthesis process to increase the specific surface area and porosity of these carbon materials. However, owing to the diversity of activators and the differences in physicochemical properties that these activators induce, the influence of activators used for the synthesis of N-doped carbon catalysts on their electrochemical performance is unclear. In this study, a series of bagasse-derived N-doped carbon catalysts is prepared with the assistance of different activators to understand the correlation between activators, physicochemical properties, and electrocatalytic performance for the CO₂ RR. The properties of N-doped carbon catalysts, such as N-doping content, microstructure, and degree of graphitization, are found to be highly dependent on the type of activator applied in the synthesis procedure. Moreover, the overall CO₂ RR performance of the synthesized electrocatalysts is not determined only by the N-doping level and the configuration of the N-dopant, but rather by the overall surface chemistry, where the porosity and the degree of graphitization are jointly responsible for significant differences in CO₂ RR performance.

Keywords: CO2 valorization; biomass; carbon activation; doping; electrocatalysis.