CsPbBrCl₂/g-C₃N₄ type II heterojunction as efficient visible range photocatalyst

Area of Science:

• Materials Science
• Environmental Chemistry
• Photocatalysis

Background:

• Photocatalytic efficiency of semiconductors is often limited by rapid recombination of photogenerated charge carriers.
• Developing novel hybrid materials by coupling semiconductors is a promising strategy to enhance catalytic performance.

Purpose of the Study:

• To synthesize and characterize a type II heterojunction comprising graphitic carbon nitride (g-C3N4) and cesium lead halide perovskite (CsPbBrCl2).
• To evaluate the photocatalytic activity of the synthesized hybrid for the degradation of complex organic effluents under visible light illumination.

Main Methods:

• Facile synthesis of g-C3N4/CsPbBrCl2 heterojunctions.
• Characterization using Mott-Schottky analysis to confirm heterojunction type.
• Density Functional Theory (DFT) calculations to elucidate charge transfer processes.
• Photocatalytic degradation experiments using cationic and anionic dyes.
• Scavenger tests to identify active radical species.

Main Results:

• The g-C3N4/CsPbBrCl2 hybrid exhibited significantly improved degradation of toxic cationic and anionic dyes compared to individual components.
• Mott-Schottky analysis confirmed the formation of type II staggered gap junctions, which suppress charge carrier recombination.
• DFT calculations supported the charge transfer mechanism within the heterojunction.
• EDTA presence enhanced degradation, indicating the role of specific active radicals.

Conclusions:

• The developed type II g-C3N4/CsPbBrCl2 heterojunction effectively enhances photocatalytic degradation of organic pollutants by minimizing charge carrier recombination.
• The hybrid material shows great potential for environmental remediation applications under visible light.