Highly stable color-tunable organic long-persistent luminescence from a single-component exciplex copolymer for in vitro antibacterial

Developing exciplex-based organic long-persistent luminescence (OLPL) materials with high stability is very important but remains a formidable challenge in a single-component system. Here, we report a facile strategy to achieve highly stable OLPL in an amorphous exciplex copolymer system via through-space charge transfer (TSCT). The copolymer composed of electron donor and acceptor units can not only exhibit effective TSCT for intra/intermolecular exciplex emission but also construct a rigid environment to isolate oxygen and suppress non-radiative decay, thereby enabling stable exciplex-based OLPL emission with color-tunable feature for more than 100 h under ambient conditions. These single-component OLPL copolymers demonstrate robust antibacterial activity against Escherichia coli under visible light irradiation. These results provide a solid example to exploit highly stable exciplex-based OLPL in polymers, shedding light on how the TSCT mechanism may potentially contribute to OLPL in a single-component molecular system and broadening the scope of OLPL applications.