Recent advances in carbon-supported non-precious metal single-atom catalysts for energy conversion electrocatalysis

Abstract

Non-precious metal single-atom catalysts (NPM-SACs) with unique electronic structures and coordination environments have gained much attention in electrocatalysis owing to their low cost, high atomic utilization, and high performance. NPM-SACs on carbon support (NPM-SACs/CS) are promising because of the carbon substrate with a large surface area, excellent electrical conductivity, and high chemical stability. This review provides an overview of recent developments in NPM-SACs/CS for the electrocatalytic field. First, the state-of-the-art synthesis methods and advanced characterization techniques of NPM-SACs/CS are discussed in detail. Then, the structural adjustment strategy of NPM-SACs/CS for optimizing electrocatalytic performance is introduced concisely. Furthermore, we provide a comprehensive summary of recent advances in developing NPM-SACs/CS for important electrochemical reactions, including carbon dioxide reduction reaction, hydrogen evolution reaction, oxygen evolution reaction, oxygen reduction reaction, and nitrogen reduction reaction. In the end, the existing challenges and future opportunities of NPM-SACs/CS in the electrocatalytic field are highlighted.

Design of Single‐Atom Catalysts for E lectrocatalytic Nitrogen Fixation

“…Due to the high specific surface area and electrical conductivity, metal-free materials are expected to be suitable catalysts. [55] Arif et al develop metal-free hollow hierarchical nanotube (HHNT) composite layered double hydroxides as electrocatalysts for ENRR. [56] The hollow hierarchical structure presents a three-dimensional structure and is rich in pore structure, which is promotes the incorporation of N 2 .…”

“…[54] Therefore, non-noble metal catalysts have attracted attention, and their surfaces can form MÀ N bonds to adsorb N 2 , which can alleviating the kinetic problem of N 2 activation. [55] However, there are fewer active sites, which leads to only lower FE and NH 3 yields for non-noble metal catalysts. Due to the high specific surface area and electrical conductivity, metal-free materials are expected to be suitable catalysts.…”

“…However, the application of the above catalysts is limited due to cost and resource issues [54] . Therefore, non‐noble metal catalysts have attracted attention, and their surfaces can form M−N bonds to adsorb N 2 , which can alleviating the kinetic problem of N 2 activation [55] . However, there are fewer active sites, which leads to only lower FE and NH 3 yields for non‐noble metal catalysts.…”

“…However, there are fewer active sites, which leads to only lower FE and NH 3 yields for non‐noble metal catalysts. Due to the high specific surface area and electrical conductivity, metal‐free materials are expected to be suitable catalysts [55] . Arif et al.…”

Chemistry boosts carbon neutrality

“…It helps decrease the energy consumption of this thermally catalytic reaction, thus reducing the usage of fossil fuels and CO 2 emissions. Lin et al [3] summarized recent advances in carbonsupported non-precious metal single-atom catalysts for energy conversion electrocatalysis. The application, challenges, and future opportunities of such catalysts in the electrochemical reactions, including CO 2 reduction, hydrogen evolution, oxygen evolution, and nitrogen reduction have also been comprehensively discussed.…”