Photon interconversion generally describes processes which change the wavelength of the emitted light upon irradiation, with a gain in photon energy (upconversion), or a splitting of the incident photon energy to create multiple photons (downconversion). The focus of this progress report is placed on halide perovskite materials and their role in upconversion by triplet–triplet annihilation and downconversion via singlet fission in organic semiconductors, and a short perspective is given into quantum cutting and lanthanide-based upconversion applications. The current advances are highlighted regarding halide perovskites and perovskite-inspired materials with varying framework and material dimensionalities, as relating to photon interconversion processes. The majority of the literature is based on 3D perovskites, which leaves room for growth for perovskite materials with varying dimensionalities. Gaps in the current field are emphasized, leading to a bright outlook on future possibilities of coupling perovskites to photon interconversion mechanisms, which can open the door for future breakthroughs in this field.

中文翻译：

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卤化物钙钛矿：光子互变进展报告

光子相互转换通常描述在照射时改变发射光波长的过程，光子能量增加（上转换），或入射光子能量分裂以产生多个光子（下转换）。这份进展报告的重点是卤化物钙钛矿材料及其在三重态上转换中的作用——通过有机半导体中的单线态裂变三重态湮灭和下转换，并简要介绍了量子切割和基于镧系元素的上转换应用。与光子相互转换过程相关的具有不同骨架和材料维度的卤化物钙钛矿和钙钛矿启发材料的当前进展得到了强调。大多数文献都基于 3D 钙钛矿，这为具有不同维度的钙钛矿材料留下了增长空间。强调了当前领域的差距，为钙钛矿与光子互变机制耦合的未来可能性带来了光明的前景，这可以为该领域未来的突破打开大门。