Fast Photoelectron Transfer in (C_ring)–C₃N₄ Plane Heterostructural Nanosheets for Overall Water Splitting

Abstract

Direct and efficient photocatalytic water splitting is critical for sustainable conversion and storage of renewable solar energy. Here, we propose a conceptual design of two-dimensional C 3 N 4 -based in-plane heterostructure to achieve fast spatial transfer of photoexcited electrons for realizing highly efficient and spontaneous overall water splitting. This unique plane heterostructural carbon ring (C ring )–C 3 N 4 nanosheet can synchronously expedite electron–hole pair separation and promote photoelectron transport through the local in-plane π-conjugated electric field, synergistically elongating the photocarrier diffusion length and lifetime by 10 times relative to those achieved with pristine g-C 3 N 4 . As a result, the in-plane (C ring )–C 3 N 4 heterostructure could efficiently split pure water under light irradiation with prominent H 2 production rate up to 371 μmol g –1 h –1 and a notable quantum yield of 5% at 420 nm.