Electronic structure modulation and heterointerface engineering in CN/Zr-MOF hybrid photocatalyst for efficient mustard gas simulant decontamination

Mustard gas remains a serious threat to human safety. The mild oxidative properties of ROS enable its selective detoxification into non-toxic sulfoxides. Integrating MOFs rich in active sites with CN to construct heterojunctions is an effective strategy to enhance ROS quantum yield. However, the presence of interfacial vacancies significantly impedes the charge carrier transport. In this study, a highly integrated hybrid photocatalyst composed of polymeric CN and zirconium-based MOF (Zr-MOF) was synthesized through in situ growth followed by annealing treatment. Extensive research evidence demonstrates that the strong interaction between CN and Zr-MOF, which can be induced by the annealing effect, induces polarity effects and structural reconstruction, optimizing charge distribution and facilitating carrier migration for enhanced charge transfer. Furthermore, the Zr-MOF exhibited exceptional O₂ adsorption at its active sites and effectively harnessed photoelectrons to produce high-energy reactive oxygen species, driving photocatalytic oxidation reactions. As a result, the CN/Zr-MOF-2 hybrid achieved complete detoxification of the mustard gas simulant CEES (dimethyl dichloroethyl sulfide) within 10 min, with a detoxification rate nearly 10 times higher than that of pure CN, which surpasses that of most previously reported materials. This work offers a sustainable solution for neutralizing hazardous chemicals.