ZnIn2S4/AgCoO2 S-scheme Heterojunction for Photocatalytic Hydrogen Evolution under Visible Light Irradition in Pure Water

The fabrication of an S-scheme heterojunction represents a highly effective approach for achieving efficient and environmentally friendly artificial photosynthesis. In this study, a highly efficient S-scheme heterojunction was developed by modifying ZnIn 2 S 4 , a kind of chrysanumi-like flower, with a two-dimensional sheet of AgCoO 2 by physical grinding method, which realized H 2 generation and H 2 O 2 generation under visible light conditions. AgCoO 2 exhibits significant potential as a cocatalyst owing to its narrow band gap, black appearance, and robust stability. Because of the difference in Fermi levels, the two-dimensional AgCoO 2 and three-dimensional ZnIn 2 S 4 are closely fitted to accelerate the charge migration between the interfaces, thus improving the photocatalytic properties of the materials. In-depth investigations utilizing in situ X-ray photoelectron spectroscopy alongside additional experimental methodologies have definitively illuminated the intricate charge partition and migration dynamics operative within the S-scheme heterojunction interface between the two catalysts. Photochemistry and photoluminescence spectroscopy further confirmed that the formation of heterojunction accelerated the migration of photogenerated charge carriers, and electron spin resonance provided further evidence for the active substances in the reaction. This study has made additional advancements in the development of efficient S-scheme heterojunction materials for driving photocatalytic water cleavage.