Microwave–Driven Interface Engineering Enhancing Electron Flow for Highly Efficient Solar NO Oxidation over rGO-Integrated NH₂-MIL125(Ti)/TiO₂

Interface design plays a pivotal role in developing high-performance photocatalysts for NO oxidation. In this work, a hierarchical rGO-integrated NH2-MIL125(Ti)/TiO2 photocatalyst was constructed using a combined liquid-phase and solid-phase microwave synthesis approach. The liquid-phase microwave process enabled the precise deposition of NH2-MIL125(Ti) on graphene oxide (GO), forming strong interfacial bonds, while the solid-phase microwave thermal shock (SMTS) transformed GO into rGO and induced the formation of TiO2 nanoparticles. This hierarchical structure established an efficient electron transport pathway, promoting charge separation and directional electron transfer to activate O2 and generate superoxide radicals (•O2–) as the primary reactive species. The resulting photocatalyst achieved remarkable NO oxidation performance, with an 81.2% NO removal efficiency and a NO3– selectivity of 98.5% under simulated sunlight. This study highlights the potential of microwave–driven interface engineering in the innovative design of photocatalysts for environmentally sustainable applications.