Nitrogen-Doped Carbon-Encapsulated Nickel Nanoparticle Catalysts Using Covalent Organic Frameworks as Templates for Electrochemical CO2 Conversion

Abstract

Electrochemical CO₂ reduction (ECR) reactions, powered by cleaner energy, possess significant promise in mitigating CO₂ emissions and achieving carbon recycling. Herein, Ni@N-C electrocatalysts with encapsulated structures are prepared using covalent organic frameworks (COFs) as templates, where COF-derived nitrogen-doped carbon (N-C) is utilized to wrap Ni nanoparticles. At the potential of −0.97 V vs. RHE, 2Ni@N-C-800 is characterized by a high current density (j = 24.2 mA cm^-2) and relatively high CO Faraday efficiency (FE_CO = 72%), reflecting its good catalytic activity. The ECR performance of 2Ni@N-C-800 is due to the cooperative interaction between Ni nanoparticles and the N-C structure, which is inferred from control and poisoning measurements. This study provides a new idea for finding efficient and stable ECR catalysts.