Construct a Heterojunction Interface to Induce and Complete Hole-Dominated Cascade Reaction

Area of Science:

• Materials Science
• Environmental Chemistry
• Photocatalysis

Background:

• Carrier separation efficiency is crucial for reactive oxygen species generation in cascade reactions.
• Constructing heterojunction interfaces is a key strategy to enhance carrier separation.
• Photo-Fenton systems offer a promising route for pollutant degradation.

Purpose of the Study:

• To engineer a self-sufficient photo-Fenton system using a CuₓO/CuS/ZnIn₂S₄ heterojunction.
• To achieve efficient degradation of amoxicillin via a hole-dominated cascade reaction.
• To investigate the role of the heterojunction interface in optimizing carrier dynamics and singlet oxygen generation.

Main Methods:

• Fabrication of CuₓO/CuS/ZnIn₂S₄ heterojunction via in situ transformation.
• Structural and compositional characterization using XRD, XPS, and TEM.
• Evaluation of photocatalytic performance for amoxicillin degradation under visible light irradiation.

Main Results:

• The CuₓO/CuS/ZnIn₂S₄ heterojunction exhibited an S-scheme band structure, enhancing carrier separation.
• The system demonstrated efficient in situ production of H₂O₂ and subsequent conversion to singlet oxygen (¹O₂).
• Amoxicillin degradation was significantly improved due to optimized carrier transfer and ¹O₂ generation.

Conclusions:

• The engineered S-scheme heterojunction effectively boosts carrier separation efficiency.
• The hole-dominated cascade reaction facilitates directional generation of singlet oxygen for pollutant degradation.
• This work presents a promising strategy for developing advanced oxidation processes for environmental remediation.