Visible Light-Triggered Release of Sulfonamides in MOF/Ag-Based Nanoparticle Composites: Performance, Mechanism, and DFT Calculations

Abstract: Visible light-responsive materials sparked wide interests due to that visible light possess some merits like no by-product formation, environmental friendliness, and nearly zero energy consumption. In this work, UiO-66-NH₂/Ag₂CO₃ (UAC-X) composites with outstanding adsorption and visible light-triggered desorption performances toward sulfonamides (SAs) like sulfamethoxazole (SMX), sulfisoxazole (SIX) and sulfamethazine (SMT) were reported. It was believed that the interactions between -NH₂ from SAs and Ag⁺ of Ag₂CO₃ (UAC-X) nanoparticles contributed to the outstanding adsorption performance toward the SAs. The conversion from Ag⁺ to Ag⁰ of the photosensitive Ag₂CO₃ (NPs) in the UAC-X composites led to the controlled diliver of SAs, in which the release performance could be tuned by the UiO-66-NH₂ proportion in UAC-X. Additionally, the DFT calculation results demonstrated that the binding energy of Ag⁺-NH₂ (BE = - 0.925 eV) is lower than the band gap of Ag₂CO₃ (BE = 2.3 eV), implying that the conversion from Ag⁺ to Ag⁰ contributed to the SAs desorption. The light-induced desorption will provide new strategies to realize environment friendly and inexpensive regeneration of adsorbents.