Lead-free copper(I) halides have been demonstrated to exhibit high photoluminescence quantum yields with high air and light stability, making them one of the most promising semiconductors for next-generation light-emitting diode devices. The low-dimensional structures and soft lattices of Cu(I) halides induce the formation of self-trapped excitons (STEs) to achieve broadband emissions with high quantum yields. Herein, the recent studies on the electronic and optical properties of Cu(I) halides (i.e., Cs₃Cu₂X₅, CsCu₂X₃, and A₂CuX₃, where A = K⁺ or Rb⁺, X = Cl⁻, Br⁻, or I⁻) are reviewed and particular emphasis is placed on the role of the dimensionality and the halide in governing the electronic and optical properties (e.g., emission color and photoluminescence efficiency) via STEs. Several optoelectronic applications of Cu(I) halides are also discussed. In the last section, perspectives and challenges for the future development of Cu(I) halides in both optoelectronic and photocatalytic applications are outlined.

中文翻译：

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用于光电应用的发光铜 (I) 卤化物

无铅卤化铜（I）已被证明具有高光致发光量子产率和高空气和光稳定性，使其成为下一代发光二极管器件最有前途的半导体之一。Cu（I）卤化物的低维结构和软晶格诱导自陷激子（STE）的形成，以实现具有高量子产率的宽带发射。在此，对Cu的电子和光学性质的最近的研究（I）卤化物（即，铯₃的Cu ₂ X ₅，CSCU ₂ X ₃，和A ₂的CuX ₃，其中A = K ⁺或R b ⁺，X =氯^- , 溴^-, 或 I ^- ) 进行了审查，并特别强调了维度和卤化物在通过 STE 控制电子和光学特性（例如，发射颜色和光致发光效率）中的作用。还讨论了 Cu(I) 卤化物的几种光电应用。在最后一节中，概述了 Cu(I) 卤化物在光电和光催化应用中的未来发展的前景和挑战。