Regulating crystallinity in linear conjugated polymer to boost the internal electric field for remarkable visible-light-driven disinfection

Abstract

• A new poly-imines, ODA-BPAH was used for photocatalysis disinfection • The high crystallinity greatly enhanced Internal electric field (IEF) • Giant IEF boosting photogenerated charge separation and transport • The ODA-BAPH exhibited excellent broad-spectrum water disinfection performance • This sterilization ability is higher than reported noble metal-free photocatalysts Conjugated linear polymers are promising metal-free photocatalysts for visible-light-driven photocatalytic water disinfection, but it was still bottlenecked by the insufficient photogenerated charge separation and transport (CST) process. Herein, we obtained the highly crystalline imine-linked conjugated linear polymer (ODA-BPAH) with a greatly enhanced CST process. The highly crystalline ODA-BPAH exhibited excellent broad-spectrum water disinfection efficiency up to 99.99999% in 1 h, which is among the reported highest of state-of-the-art photocatalysts. The crystallinity of ODA-BPAH was regulated by simply turning the solvent and the experiment results revealed that the ODA-BPAH with high crystallinity exhibited higher internal electric field strength and photocatalytic performance than that with low crystallinity, which indicates that higher crystallinity in linear conjugated polymers contributes to superior CST efficiency as well as the generation of reactive oxygen species. This work highlights the impact of polymer crystallinity on the internal electric field and proves that linear poly-imine could be a new type of promising metal-free photocatalyst for water treatment.