Metal cation substitution of halide perovskite nanocrystals

Recent years have seen a rapid development of lead halide perovskite (LHP) nanocrystals (NCs) as new and promising functional nanomaterials, which exhibit strong potential in a wide range of optoelectronic applications due to their superior properties and solution-processable advantages. However, to promote their progress in commercialization, overcoming the drawbacks of intrinsic lead toxicity and optimizing material performance are important and must be solved using alternative metal ions to replace Pb ions. In this review, we primarily summarize the recent development of lead-substitution strategies, which focus on the commonalities and differences of their functionalities that are induced by various doped ions. After a brief introduction to the synthesis, nucleation and growth of all-inorganic LHP NCs, a deep discussion of the crystalline structure, electronic band structure, defect states, exciton binding energy, exciton photodynamic process and stability is followed. Specifically, we highlight the importance of both theoretical calculations and experimental characterizations to establish indicative guidelines for high-performance semiconductor nanomaterials. Finally, the light emission applications are discussed, and several issues concerning future research on the controllable synthesis of halide perovskite NCs with low toxicity, superior reproducibility and properties are outlined.