Lead halide perovskites with nanoscale geometries have received recent attention due to the defect-tolerant high photoluminescence quantum yield at tunable emission wavelengths and the possibility of room-temperature synthesis that does not compromise the physical properties of the materials. These characteristics offer opportunities to advance displays that cover the widest perceivable color. However, lead toxicity obstructs the commercialization of this technology. Therefore, recent efforts have investigated lead-free halide perovskite nanocrystals. Here, we provide our perspectives on the most exciting achievements in the materials design and photophysical properties of lead-free perovskite nanocrystals, particularly for applications in light-emitting devices. This Perspective includes a short summary on the characteristic features of halide perovskite nanocrystals; discussion on the candidate elements to replace lead; methods to prepare colloidal lead-free perovskite nanocrystals; methods to control and enhance the optical properties; a recent demonstration of utilizing lead-free perovskite nanocrystals in light-emitting devices; and an outlook on the field.

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发光器件用无铅钙钛矿纳米晶体

具有纳米级几何形状的卤化铅钙钛矿受到近期关注，这是由于在可调节的发射波长下耐缺陷的高光致发光量子产率以及室温合成的可能性不会损害材料的物理性能。这些特性为改进覆盖最广泛颜色的显示器提供了机会。然而，铅毒性阻碍了该技术的商业化。因此，最近的努力已经研究了无铅卤化物钙钛矿纳米晶体。在这里，我们提供有关无铅钙钛矿纳米晶体在材料设计和光物理性能方面最令人激动的成就的观点，尤其是在发光器件中的应用。本《观点》简要概述了卤化物钙钛矿纳米晶体的特征。讨论替代铅的候选元素；制备胶体无铅钙钛矿纳米晶体的方法；控制和增强光学性能的方法；最近在发光器件中利用无铅钙钛矿纳米晶体的演示；以及该领域的前景。