P-Type AsP Nanosheet as an Electron Donor for Stable Solar Broad-Spectrum Hydrogen Evolution

Although research progress on mimicking natural photosynthesis for solar-to-fuel conversion has been continuously made, exploring broadband spectral-responsive materials with suitable band positions and high stability still remains a huge challenge. Herein, we, for the first time, report novel AsP nanosheets (NSs) with P-type semiconducting property and enough negative conduction band, which can work as a stable near-infrared (NIR) region-responsive electron donor for water reductive hydrogen (H₂) production. To mimic photosystem I, Au nanorods (NRs) act as electron transport media, which are also responsible for the enhanced electric field nearby, and 1T-MoS₂ NSs as a hydrogen evolution catalyst are orderly coupled with AsP NSs with a sheet-rod-sheet structure by electrostatic self-assembly. The cascaded band level alignment enables unidirectional electron flow from AsP to Au and then to MoS₂, and the optimum H₂ production rate of the MoS₂-Au-AsP ternary heterojunction reaches 125.52 μmol g^-1 h^-1 with good stability even after being stored for several months under light irradiation with a wavelength longer than 700 nm. This work provides a platform that is energetically tailored to drive a solar broad-spectrum fuel generation, including CO₂ reduction and N₂ fixation.