Construction of a thiophene-based conjugated polymer/TP-PCN S-scheme to enhance visible-light-driven photocatalytic activity: promotion of wound healing in super-resistant bacterial infections

Abstract

S-scheme heterojunctions have garnered significant attention in the field of photocatalytic antimicrobials due to their superior charge separation efficiency and higher redox capacity. In this study, an innovative linear conjugated polymer (PCO) was combined with fragmented carbon nitride (TP-PCN) to create PCO/TP-PCN organic-organic S-scheme heterojunctions, which markedly enhanced the photocatalytic antimicrobial performance. The composite (PCO-7/TP-PCN) demonstrated the ability to combat bacterial infections under visible light irradiation, effectively eradicating approximately 2.16 × 10⁷ cfu/ml MRSA within 6 min. This exceptional photocatalytic performance can be attributed to the successful formation of an S-scheme heterojunction between PCO and TP-PCN, as well as the interaction of surface functional groups of PCO-7/TP-PCN with bacteria. Results from UV–Vis-NIR DRS and in situ-XPS experiments indicated a significant enhancement in carrier transport rate through the establishment of a built-in electric field and energy band bending at the interface. In vitro and in vivo experiments further demonstrated that PCO-7/TP-PCN not only exhibited potent antimicrobial activity under visible light irradiation but also promoted angiogenesis to inhibit inflammatory responses. Therefore, it can be concluded that this organic-organic S-scheme heterojunction photocatalyst holds great potential for development as a promising new generation of efficient antimicrobial materials, which could aid in preventing bacterial infection of wounds and ensuring effective wound healing.