Efficient visible-light-responsive CN/In2O3/MoO3 heterojunctions for sustainable H2 generation and environmental remediation

Graphitic carbon nitride (CN) and Indium(III) oxide (In2O3) are appealing visible-light-driven semiconductor photocatalysts due to their low cost, facile synthesis, and stability. Its applications endured limitations by photocorrosion, an insignificant optical band gap for solar-light applications, and improper distinction between photogenerated electron-hole pairs. A unique ternary nanocomposite (CN/In2O3/MoO3-0.2) was designed to enhance the efficiency of CN and In2O3 materials forphotocatalytic H2 generation and organic contaminant degradation under visible light. The optimized composite showed an exceptional H2 generation rate of 2706.5 µmol g− 1 h− 1, demonstrating substantial synergistic effects among all pristine and composite material. Besides energy generation, the material demonstrated outstanding performance in environmental cleanup, with a 91.4% degradation efficiency of malachite green (MG). The improved catalytic activity stems from the buildind of a Z-scheme heterojunction, which effectively promotes the separation and migration of electric charge carriers while reducing recombination losses. Density functional theory (DFT) confirm the formation of an intensified built-in electric field and Z-scheme charge transfer mechanism in the ternary heterostructure, providing a quantitative explanation for its excellent charge separation capability and photocatalytic activity. Stability experiments validated the reusbbility of photocatalysts, which maintained 77.8% degradation efficiency after five consecutive cycles. Radical scavenging tests showed, during the degradation process, that holes (h⁺) and hydroxyl radicals (·OH) are the main active species. This research provides important insights into the development of multifunctional photocatalysts for sustainable H2 production and pollutants degradation performance.