Here we review an emerging class of 2D layered metal-halide perovskites that exhibit important photophysical behavior involving inorganic exciton-to-molecular triplet energy flow. These novel systems have potential to impact several energy-related fields and processes, including optoelectronics, photon upconversion strategies, and triplet-based photocatalysis. Early studies provided initial guidance and revealed several intriguing questions that more recent developments, in terms of both expanded and diversified compositional tuning and more sophisticated characterization, have begun to answer. These questions center around the delicate interplay between physical and electronic structure that is perturbed by choice of perovskite structural motif and organic spacer properties. In addition to their distinct natures, the energy offsets between the metal-halide and molecular excitons can be leveraged for a variety of unique effects and emergent properties, including fast interlayer energy transfer. We review the key advances with an eye toward strategies for controlling photophysical outcomes based on structure–energy–function relationships.

中文翻译：

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层状二维杂化金属卤化物钙钛矿中的层间三重敏化发光

在这里，我们回顾了一类新兴的二维层状金属卤化物钙钛矿，它们表现出重要的光物理行为，涉及无机激子到分子的三重态能量流。这些新系统有可能影响几个与能源相关的领域和过程，包括光电子学、光子上转换策略和基于三重态的光催化。早期的研究提供了初步的指导并揭示了几个有趣的问题，这些问题在扩展和多样化的成分调整以及更复杂的表征方面，最近的发展已经开始回答。这些问题集中在物理和电子结构之间微妙的相互作用上，这种相互作用受到钙钛矿结构基序和有机间隔物特性的选择的干扰。除了它们独特的性质，金属卤化物和分子激子之间的能量偏移可用于各种独特的效应和新兴特性，包括快速层间能量转移。我们回顾了基于结构-能量-功能关系控制光物理结果的策略的关键进展。