Theoretical inspection of high-efficiency single-atom catalysts based onπ-πconjugated holey graphitic g-C_(7)N_(3)monolayer:Marvelous water-splitting and oxygen reduction reactions activities  

作　　者：Chunyao Fang Xihang Zhang Qiang Zhang Di Liu Xiaomeng Cui Jingcheng Xu Chenglong Shi Renxian Qin 

机构地区：[1]Department of Physics,University of Shanghai for Science and Technology,Shanghai 200093,China [2]School of Materials and Chemistry,University of Shanghai for Science and Technology,Shanghai 200093,China

出　　处：《Journal of Materials Science & Technology》2024年第31期143-157,共15页材料科学技术(英文版)

基　　金：supported by the National Natural Science Foundation of China(No.21905175).

摘　　要：Hydrogen evolution reaction(HER)and oxygen evolution/reduction reaction(OER/ORR)relying on high-performance and low-cost single-atom catalysts(SACs)driven by renewable energy sources offer a sustainable route to carbon-neutral chemicals and fuels.Herein,first-principles calculations were performed to investigate the catalytic HER/OER/ORR activity of a novel graphitic carbon nitride monolayer(g-C_(7)N_(3))supported single transition metal(TM@g-C_(7)N_(3)).High stability as well as positively charged active site(TM-site)and desirable electrical conductivity lay the foundation for TM@g-C_(7)N_(3)acting as efficient HER/OER/ORR electrocatalysts.We screened out the non-noble-metal Rh@g-C_(7)N_(3)SAC exhibiting great potential as the trifunctional electrocatalysts for water splitting(η^(HER)=0.06 V andηOER=0.46 V)and a metal-air battery(η^(ORR)=0.28 V)on both kinetic and thermodynamic scales,whereas the Ni@g-C_(7)N_(3)can be served as a bifunctional OER/ORR catalyst with a low overpotential of 0.33 V/0.31 V,for both of which the high thermodynamic stability and oxidation barrier guarantee their outstanding performances at ambient conditions.The mechanism analysis indicates the filling of d-orbital electrons of TM-atom can play an important role in determining the value of an energy descriptor(ΔGOH*),and the suitableΔGOH*values make for the TM@g-C_(7)N_(3)candidates to possess favorable OER/ORR overpotential.Particularly,the Rh-d orbital of Rh@g-C_(7)N_(3)is evidently hybridized with the OH*-p orbital,resulting in the lone electrons initially distributed in the antibonding orbital pairing up and occupying the downward bonding orbital,ensuring OH*can be adsorbed on Rh@g-C_(7)N_(3)appropriately.Moreover,multiple-level descriptors including d-band center,COHP,Nd,andφare used to reveal the origin of the electrocatalytic activity.

关 键 词：Single atom catalysts Hydrogen evolution reaction Oxygen evolution reaction Oxygen reduction reaction Monolayer g-C_(7)N_(3) 

分 类 号：O64[理学—物理化学]