Efficient Co2 Reduction to Co by Tuning Intrinsically and Externally Dispersed Ni Single-Atom Catalysts

Abstract

With the increasing global climate change and energy crisis, the development of efficient carbon dioxide reduction reaction (CO2RR) catalysts has become an important research direction in the field of chemistry and materials science. The aim of this study is to explore the possibility of obtaining atomically dispersed Ni Single atom catalysts for efficient CO2RR generation of CO by tuning the endogenous and exogenous factors. Here, we employ the metal-organic framework material ZIF-8 as a carrier to achieve effective dispersion and immobilization of nickel (Ni) atoms by taking advantage of its unique pore structure and tunability. Ni Single atom catalysts with excellent electrocatalytic performance were successfully prepared by precisely controlling the synthesis conditions, including temperature and concentration. The catalyst exhibited high selectivity and stability in the CO2RR process with high Faraday efficiency and current density for CO generation. At -0.88 V vs. RHE, the catalyst achieved up to 99.6% CO2 conversion. The electronic structure of the active center of the Ni single atom catalyst and its interaction mechanism with the reaction intermediates were further revealed by a combination of theoretical calculations and experimental characterization, which provided a theoretical basis and experimental guidance for the design of more efficient CO2RR catalysts. The results have revealed the conversion efficiency of CO2 to CO can be significantly enhanced by rationally designing and regulating the internal and external factors of the catalyst, which provides a new idea and method for solving the problems of energy conversion and environmental protection. It not only expands the application of single atom catalysts in the field of electrocatalysis, but also opens up a new way for the resource utilization of CO2.

Keywords: CO2 electroreduction, Metal-Nitrogen-Carbon, Ni single atom catalysts, ZIF-8, CO