Recent advances in lead halide perovskite single crystals for optoelectronic devices

Over the past decade, perovskite materials have driven significant innovations in optoelectronics due to their exceptional photoelectric performance, drawing substantial global research attention. Specifically, the certified power conversion efficiency (PCE) of single-junction perovskite solar cells has reached 27.37%, the X-ray light yield of perovskite scintillators has attained 1 20 000 photons per MeV, and the external quantum efficiencies (EQEs) of perovskite light-emitting diodes (LEDs) have reached 26.4% (blue light), 32.5% (red light), and 31% (green light), respectively. Despite their high optoelectronic potential, surface defects and grain boundaries in perovskite polycrystalline films remain key barriers to performance improvement and commercialization. In contrast, single-crystal perovskites, characterized by minimal grain boundaries and low defect densities, emerge as superior candidates for high-performance optoelectronic devices. They also serve as an ideal platform for investigating and elucidating the intrinsic properties of perovskite materials. Therefore, this review outlines recent progress in perovskite single-crystal crystallization, properties, fabrication and applications, clarifies intrinsic structure-property and growth-defect relationships, advances a device-demand-driven material design concept, and offers critical insights into challenges, prospects and future commercialization. We believe that this review will provide valuable insights and inspiration for future research endeavors in this domain.