Fast Photoelectron Transfer in (C)-CN Plane Heterostructural Nanosheets for Overall Water Splitting.

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 CN-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)-CN 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-CN. As a result, the in-plane (C)-CN heterostructure could efficiently split pure water under light irradiation with prominent H production rate up to 371 μmol g h and a notable quantum yield of 5% at 420 nm.