Enhanced singlet oxygen production over a photocatalytic stable metal organic framework composed of porphyrin and Ag

Porphyrin is an important photosensitizer for singlet oxygen (O-1(2)) formation. However, porphyrin derivatives still display low efficiency and difficult recovery. In this work, an Ag-based MOFs (AgTPyP; TPyP, 5,10,15,20-tetra(4-pyridyl) porphyrin) is synthesized. Compared with ligand TPyP, AgTPyP shows nearly 100% conversion and selectivity in the photocatalytic selective oxidation of sulfides to sulfoxides and obvious photodynamic therapeutic effect under visible light. Combined characterizations suggest that O-1(2) is the only active oxygen species, which is due to the large exciton binding energy and narrow energy gap between the lowest excited singlet state (S-1) and the lowest triplet state (T-1) induced by the presence of Ag+ ion. The selectivity and conversion efficiency of five-cycle experiments do not decrease, indicating the excellent stability of AgTPyP. This work provides an alternative approach to simultaneously enhance the exciton effect of porphyrin and stabilize Ag-based photocatalysts. (C) 2021 Published by Elsevier Inc.

Automated summary

In this study, an Ag-based MOFs, AgTPyP, was synthesized and showed high efficiency and stability in the selective oxidation of sulfides to sulfoxides, along with a significant photodynamic therapeutic effect. The material provides an alternative approach to enhance the efficiency of porphyrin by enhancing the exciton effect and stabilizing Ag-based photocatalysts.