Zero-dimensional perovskite ferroelectric [C₄N₂H₁₄][SbCl₅] for self-powered visible-blind ultraviolet photodetector

Since the intrinsic spontaneous polarization facilitates the efficient separation of photogenerated charge carriers, perovskite ferroelectrics with wide bandgaps hold immense promises for the development of self-powered ultraviolet (UV) photodetectors. However, such self-powered ferroelectric photodetectors with superior performance are still scarce, thereby constraining their broader applicability. Herein, we introduce a zero-dimensional (0D) leadless hybrid perovskite ferroelectric, namely [C₄N₂H₁₄][SbCl₅], distinguished by a remarkable P_s of approximately 2.6 μC/cm² and an elevated Curie temperature of 455 K, surpassing that of BaTiO₃ (393 K) and most of the molecular ferroelectrics. Notably, leveraging its wide bandgap of 3.49 eV, we have successfully fabricated a self-powered visible-blind UV photodetector. This device boasts a zero-bias photocurrent reaching up to 11.65 μA/cm², a high open-circuit voltage of −0.57 V, and a long carrier lifetime of 1.12 ms. This research presents a viable strategy for the exploration of wide-bandgap 0D perovskite ferroelectrics and paves the way for their utilization in the realm of self-powered visible-blind UV photodetector.