Nitrogen-Doped Triphenylene-Graphdiyne as Metal-Free Multifunctional (Photo)Electrocatalysts for Overall Water Splitting

Abstract

Hydrogen (H 2 ) produced by electrochemical (EC) and photoelectrochemical (PEC) overall water splitting is regarded as promising clean energy technologies, while exploring low-cost and high-efficient catalysts remains a challenging task. Herein, we demonstrate the catalytic activities of nitrogen-doped triphenylenegraphdiyne (N@TP-GDY) monolayers using first principles calculations in combination with nonadiabatic molecular dynamics. Our results show that the introduction of sp/sp 2 -hybridized N atoms can greatly regulate the electronic structures of TP-GDY monolayer, presenting appealing bifunctional EC performance with low overpotentials of 0.06 and 0.49 V for hydrogen evolution reaction (HER) and oxygen evolution reaction (OER), respectively. Meanwhile, the redox ability of the photogenerated electrons and holes in the N@TP-GDY systems is strong enough to drive HER and OER processes at acid and alkaline conditions, respectively. Moreover, the lifetime of the photogenerated carriers is greatly improved up to