Synergistic Interface Engineering in Mo-CN/InP-NBOC Ternary Composites for Efficient Photocatalytic NO Oxidation with Ultralow NO2 Byproduct Generation

The substantial presence of nitrogen oxides (NO and NO2) in outdoor environments detrimentally impacts natural ecosystems and exerts significant influence on urban climates. Conventional NOx treatment methods frequently suffer from challenges such as harsh reaction conditions and high energy consumption. Consequently, the development of advanced photocatalytic systems to efficiently degrade NOx while minimizing the formation of toxic byproducts represents a critical challenge in environmental catalysis. In this study, a novel ternary composite material (5% Mo-CN/InP-NBOC) was constructed via hydrothermal synthesis and surface modification strategies, achieving 42% NO oxidation efficiency under visible light irradiation with a mere 0.9% NO2 generation rate. This performance demonstrates efficient photocatalytic NO oxidation while effectively suppressing NO2 production. Systematic characterization techniques, including XRD, TEM, and XPS, confirmed the successful integration of InP quantum dots (5–10 nm) and amorphous Mo-CN onto NBOC nanosheets, forming an intimate heterojunction structure. PL and ESR analyses revealed that Mo-CN enhances charge carrier separation and governs the NO oxidation process through the activation of dual free radical pathways (•O2⁻ and •OH). This work establishes a "quantum dot-primary catalyst-cocatalyst" ternary collaborative design paradigm, providing experimental evidence and theoretical models to address the challenges of synergistic optimization among activity, selectivity, and stability in photocatalytic NOx treatment.