Room temperature preparation of novel g-C3N4/RuNP/ZIF-8 Z-scheme heterojunction for solar-light driven H2 generation

We present a novel approach for the room temperature synthesis and integration of Ru nanoparticles into a Z-scheme heterojunction comprising graphitic carbon nitride (CN) and zeolitic imidazolate framework-8 (ZIF-8). This heterojunction demonstrates outstanding efficiency in sunlight-driven hydrogen (H2) generation via water splitting. Various structural and spectroscopic analyses elucidate Ru nanoparticles' successful incorporation and synergistic effects within the CN/ZIF-8 heterojunction because the decrease in interplanar spacing due to π-π stacking interactions between aromatic rings of tri-s-triazine in CN and imidazole rings in ZIF-8. The Z-scheme configuration facilitates efficient charge separation and promotes H2 production. Additionally, Ru nanoparticles offer alternative electron transfer pathways, enhancing carrier separation and prolonging the lifespan of photoinduced charges compared to CN and ZIF-8 alone. Notably, RZCN-2 heterojunction exhibited significantly enhanced hydrogen production, reaching 5245 μmol g−1 h−1. By analyzing work functions and energy band structures, we demonstrate that the strong interfacial electric fields across the Z-scheme heterojunction effectively mitigate the recombination of photogenerated charges while maintaining the necessary redox capacity for efficient H2 production. The room temperature synthesis and integration of Ru nanoparticles provide a practical and effective strategy for optimizing photocatalytic activity and promoting sustainable energy conversion, thereby advancing photocatalytic technologies.