X-ray-activated ultra-long UVA persistent luminescence from a Bi-doped perovskite LaGaO₃ for photodynamic activation

Ultraviolet (UV) emitting persistent luminescence (PersL) materials have aroused significant interest, owing to their unique self-illuminating high-photo-energy feature under excitation-free conditions. In particular, the advent of X-rays as a charging source for UV PersL has facilitated the control of PersL properties and triggered a breakthrough in possible applications such as X-ray imaging techniques, phototherapy, photocatalysis, and optical information storage. Here, we present novel PersL materials that exhibit ultra-long UV emission for over 2000 h, as detected with a spectrometer. Experimental characterization revealed that the intrinsic oxygen vacancies associated with the local structure of the perovskite LaGaO₃ can function as traps, which have super capabilities in energy collection and storage triggered by X-ray irradiation. Notably, this design concept is guided by utilizing an oxygen-defect perovskite as a host, which can serve as powerful guidance for expediting the discovery of new PersL materials. Moreover, due to excellent UV PersL performances, the proposed photodynamic therapy (PDT) platform LaGaO₃:Bi,Sb@g-C₃N₄ demonstrates excellent PDT efficiency in vivo using low-dose X-ray irradiation. Our discovery of this UV PersL material is expected to provide directional solutions and novel perspectives for the development and application of UV luminescence technology.