Deposition of Silver Nanostructures on Covalent Organic Frameworks for Photocatalytic Degradation of Sulfur Mustard Simulants

Sulfur mustard (HD) poses a serious threat to society due to its dramatic toxicity, and thus, exploring efficient catalysts for the degradation of HD is of great significance from the perspective of national health and social security. Photocatalytic oxidation of HD is considered an effective detoxification method due to its mild reaction conditions and high selectivity. The emerging photocatalyst of covalent organic frameworks (COFs) with tunable structure and unique optical properties has attracted wide interest due to their great potential in HD decontamination. Herein, a photosensitive COF (TAPP-TFPT) was constructed by the Schiff base reaction, and then, a facile postmodification strategy was proposed to deposit silver nanoparticles on TAPP-TFPT (Ag@TAPP-TFPT) to enhance the photocatalytic degrading performance on HD simulants. Under the irradiation of visible light, both superoxide ion (O-2(center dot-)) and singlet oxygen (O-1(2)) were produced by Ag@TAPP-TFPT, and then, HD simulants can be selectively degraded into nontoxic bis(2-chloroethyl) sulfoxide with a half-life (t(1/2)) of 6.5 min and excellent reusability. This work demonstrates that postmodification of COFs offers a promising direction for the rational design of photocatalysts with good selectivity and high efficiency toward degradation of chemical warfare agents.