Regulating carrier transfer route via 1D-2D junction on TiO2 nanorods intercalated with N-doped γ-graphyne nanosheets.

One-dimensional TiO 2 nanostructure has been widely studied in the domain of photoelectrochemical water splitting. Nevertheless, the wide bandgap and fast carriers recombination of TiO 2 restrain its performance. In this study, two-dimensional N-doped γ-graphyne nanosheets were synthesized and employed in the reasonable design of TiO 2 heterostructure, facilitating carrier migration and water oxidation reaction. The photocurrent density of photoanode composed of N-doped γ-graphyne/TiO 2 nanorods reaches 1.48 mA cm−2, 1.72 times that of pristine TiO 2 at a bias of 1.23 V (vs. RHE). Meanwhile, the calculated applied bias photon-to-current efficiency increases from 0.25 % to 0.56 %. The combination of TiO 2 nanorods with layered semiconductive N-doped γ-graphyne contributes to the construction of charge transfer channels, regulating surface states and reaction sites, promoting the hole storage, and reducing the free energy barrier in the velocity determination process. This study sheds light on the design of N-doped γ-graphyne modified catalysts and facilitates their application in photoelectrochemical and photoelectrocatalytic fields. [Display omitted] • N-doped γ-graphyne/TiO 2 nanorod arrays heterojunction was successfully constructed. • The photocurrent density and photoconversion efficiency are obviouly elevated in photoelectrocatalytic water splitting. • The regulation of band engineering, charge transfer channels and reaction kinetics are achieved. • N-doped γ-graphyne nanosheets provide fast transfer channels and active sites for carrier migration and charge reaction. [ABSTRACT FROM AUTHOR]