Theoretical investigation of HER/OER/ORR catalytic activity of single atom-decorated graphyne by DFT and comparative DOS analyses

Multifunctional catalysts for hydrogen evolution reaction (HER), oxygen evolution reaction (OER), and oxygen reduction reaction (ORR) play a key role in the development of electrochemical energy systems. Moreover, single metal atoms embedded in a two-dimensional material substrate have emerged as outstanding catalysts. Owing to its large surface area and novel electronic properties, graphyne (GY) is a promising substrate for the fabrication of single-atom catalysts (SACs). By doping foreign atoms of different types on GY, their local electronic/chemical environment and catalytic performance would be improved. Based on recent experimental advances, we used density functional theory (DFT) simulations to identify a suitable series of co-decorated GY materials, with boron-, nitrogen-, phosphorus-, and sulfur-doped GY (3B-GY, 3N-GY, 3P-GY, 3S-GY) as the two-dimensional substrate, and transition metal (TM) atoms (Sc to Zn) as the single-atom centers. Our screening process showed that Co@GY and Ni@3B-GY would be highly promising multifunctional electrocatalysts for HER/OER/ ORR. Then, we built quantitative structure-property relationship (QSPR) between electronic density of states (DOS) structure and catalytic performance using comparative DOS analysis (CoDOSA). The present results further support the development and application of d-band center theory. Our work identifies promising codecorated GY for HER/OER/ORR and provides quantitative information on their DOS.