A New Model of Carbon Nitride as a Substrate to Support Single Metal Atom

作者：Dianhui Pan, Shengwei Deng, Liang Chen, Ziqi Tian · 发表于：The Journal of Physical Chemistry C · 年份：2024 · DOI：10.1021/acs.jpcc.4c00975 · 被引用次数：14 · 研究领域：Advanced Photocatalysis Techniques、Catalytic Processes in Materials Science、Nanomaterials for catalytic reactions

Carbon nitrides are commonly employed as substrates to anchor single metal atoms. Numerous theoretical studies have previously characterized these single-atom systems using the pristine g-C 3 N 4 structure, featuring a C 6 N 7 motif. However, the relatively large pores in g-C 3 N 4 may not effectively coordinate with metal cations, resulting in discordance with the coordination environment determined by experimental characterization. In this study, we introduce a novel model denoted as CN-N 4, which preserves the essential g-C 3 N 4 motif, while offering four nitrogen sites for metal binding. Compared with g-C 3 N 4, the binding affinity between the metal and this new substrate model is significantly enhanced, similar to that of a commonly studied nitrogen-doped graphene model (N-gra). Additionally, we have assessed the catalytic performance in various reactions, including the hydrogen evolution reaction (HER), carbon dioxide reduction reaction (CO 2 RR), and oxygen reduction reaction (ORR). The CN-N 4 -supported system exhibits activity comparable to that of the corresponding N-gra-supported species. Fe- and Co-centered SACs can be promising catalysts for ORR, and relatively stable Cu- g -C 3 N 4 is active to HER and CO 2 RR, consistent with reported experiments. In addition, V-CN-N 4 and Rh-CN-N 4 are predicted to be candidates to catalyze the HER and ORR, respectively. We suggest that the CN-N 4 model aptly captures the local structure of carbon nitride-based materials wit...