Heterointerface Engineering of In₂S₃/Ag₂S S-Scheme Photocatalyst Toward Solar Hydrogen Peroxide Photosynthesis

Area of Science:

• Materials Science
• Photocatalysis
• Green Chemistry

Background:

• The anthraquinone process for hydrogen peroxide (H2O2) production is energy-intensive.
• Developing efficient semiconductor photocatalysts for sustainable H2O2 synthesis is crucial.
• Challenges exist in optimizing semiconductor systems for oxygen reduction to H2O2.

Purpose of the Study:

• To construct and evaluate an In2S3/Ag2S heterostructure for enhanced H2O2 production.
• To investigate the interfacial properties and charge dynamics of the heterostructure.
• To demonstrate a feasible approach for designing transition metal chalcogenides (TMCs)-based photocatalysts.

Main Methods:

• Cation-exchange strategy to synthesize the In2S3/Ag2S heterostructure.
• Spectroscopic analysis to identify active species.
• Radical trapping experiments to elucidate the reaction pathway.
• Band alignment engineering for improved visible-light absorption and carrier migration.

Main Results:

• Atomic-level interfacial modulation in the In2S3/Ag2S heterostructure.
• Enhanced charge separation and significantly boosted H2O2 production.
• Identification of a favorable two-electron oxygen reduction pathway.
• Improved photocatalytic performance due to tailored band alignment and efficient carrier migration.

Conclusions:

• The In2S3/Ag2S heterostructure demonstrates high efficiency for photocatalytic H2O2 synthesis.
• The cation-exchange strategy enables precise interfacial control for optimized photocatalysis.
• This work advances solar-to-chemical energy conversion and offers a sustainable H2O2 production method.