Photothermal-Assisted Solvent-Free Decontamination of a Nerve Agent Simulant Using UiO-66-NH₂@CNT Hybrids

Chemical warfare agents (CWAs) pose severe threats to human health and the environment because of their extreme toxicity. Conventional liquid-phase decontamination processes can present limitations, including potential equipment corrosion, generation of secondary liquid waste, and increased operational complexity. To overcome these challenges, we report a solar-assisted process intensification strategy for solvent-free decontamination of toxic organophosphorus compounds using UiO-66-NH₂@carbon nanotube (CNT) hybrid platforms. Incorporation of CNTs (optimized at 5 wt%) enables efficient solar-to-thermal conversion, resulting in rapid photothermal self-heating to 85 °C under simulated solar irradiation (1000 W m^-2). This localized thermal effect contributes to accelerated DMMP removal within the MOF-based hybrid structure, thereby partially alleviating the kinetic limitations typically associated with solvent-free reactions. Consequently, the optimized hybrid achieves 94% removal of dimethyl methylphosphonate (DMMP), a representative sarin simulant, within 10 min under humidity-conditioned, solvent-free conditions, representing a 27% improvement compared with pristine UiO-66-NH₂. This decontamination platform eliminates the need for chemical solvents and external energy input, thereby mitigating secondary contamination and reducing the environmental footprint. By integrating the catalytic framework of Zr-based MOFs with the photothermal capability of CNTs, this study presents a sustainable engineering strategy for advanced defense and environmental protection.