Linker Independent Regioselective Protonation Triggered Detoxification of Sulfur Mustards with Smart Porous Organic Photopolymer

The development of efficient metal-free photocatalysts for the generation of reactive oxygen species (ROS) for sulfur mustard (HD) decontamination can play a vital role against the stockpiling of chemical warfare agents (CWAs). Herein, one novel concept is conceived by smartly choosing a specific ionic monomer and a donor tritopic aldehyde, which can trigger linker-independent regioselective protonation/deprotonation in the polymeric backbone. In this context, the newly developed vinylene-linked ionic polymers (TPA/TPD-Ionic) are further explored for visible-light-assisted detoxification of HD simulants. Time-resolved-photoluminescence (TRPL) study reveals the protonation effect in the polymeric backbone by significantly enhancing the life span of photoexcited electrons. In terms of catalytic performance, TPA-Ionic outperformed TPD-Ionic because of its enhanced excitons formation and charge carrier abilities caused by the donor-acceptor (D-A) backbone and protonation effects. Moreover, the formation of singlet oxygen (O-1(2)) species is confirmed via in-situ Electron Spin Resonance (ESR) spectroscopy and density functional theory (DFT) analysis, which explained the crucial role of solvents in the reaction medium to regulate the (O-1(2)) formation. This study creates a new avenue for developing novel porous photocatalysts and highlights the crucial roles of sacrificial electron donors and solvents in the reaction medium to establish the structure-activity relationship.

Automated summary

The study introduces a novel concept by selecting a specific ionic monomer and a donor tritopic aldehyde to trigger linker-independent regioselective protonation/deprotonation in the polymeric backbone. The protonation effect significantly enhances the lifetime of photoexcited electrons in the polymeric backbone. The TPA-Ionic outperforms TPD-Ionic in terms of catalytic performance due to its enhanced exciton formation and charge carrier abilities.