Recent advances in stable halide perovskite nanocrystals for optoelectronic devices, biological imaging, and X-ray...

Halide perovskite nanocrystals (HPNCs) have excellent optoelectronic properties, but their applications are still limited by instability and lead toxicity. This review highlights significant advancements in enhancing the structural stability and photoelectrical properties of HPNCs through internal crystal stabilization and external protection. One approach involves internal lattice anchoring through ion doping and heterostructure construction strategies, while the other focuses on reducing the crystal surface defects and shielding from external environmental stimuli via core/shell structure and surface modifications. This review also emphasizes the key applications of stable HPNCs, including efficient optoelectronic devices and biological imaging using visible light and X-rays, while analyzing the impact of material composition, device structure, and other critical parameters on their performance and stability. Ion-doped and heterostructured HPNCs excel in photodetectors, surface-modified HPNCs are preferred for solar cells and LEDs, and core/shell HPNCs offer distinct advantages for biological applications. The most pressing challenges are standardizing testing parameters for HPNC material stability, device-level packaging, and developing lead-free HPNC systems to address the gaps in commercial applications of HPNCs. This review seeks to inspire innovative synthesis strategies for stable HPNCs and their derivatives, aiming to realize ultra-stable, efficient, non-toxic, and eco-friendly optoelectronic devices and biological detection or imaging applications.