Fluorescence thermometry has garnered significant attention for its noninvasive, remote, highly sensitive, and rapid temperature measurement capabilities. However, achieving superior sensitivity at high temperatures remains a persistent challenge. Herein, a series of Rb2−xCsxHfCl6: y%Te4+ perovskites are synthesized to investigate the impact exerted by A‐site regulating regarding the luminescence efficiency and temperature‐responsive capabilities. Te4+ doping significantly enhances luminescence intensity, with the broadband yellow light resulting from electron–phonon coupling within the soft lattice, driven by self‐trapped exciton emission. Furthermore, A‐site regulation demonstrates that increasing Cs⁺ content induces enhanced Jahn–Teller distortion, thereby boosting luminescence efficiency. However, the pure Rb sample exhibits the lowest thermal activation energy, as the temperature rises, increased phonon‐exciton coupling and the defect activity accelerate the nonradiative recombination, drastically decreasing fluorescence lifetime by two orders of magnitude from 300 to 390 K. Utilizing this exceptional thermal sensitivity, a lifetime‐based fluorescence thermometer is developed, attaining a breakthrough relative sensitivity reaching 20.69% K−1 at 390 K, with high repeatability across multiple heating and cooling cycles. Additionally, a high‐temperature warning system for lubricating oil pipelines is designed, demonstrating robust monitoring capabilities. This work offers a new perspective on developing highly sensitive thermometers that utilize halide perovskites for high‐temperature applications.

中文翻译：

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调节用于荧光测温的 Te4+ 掺杂卤化铪钙钛矿的 A 位合金化，在高温下实现突破性的灵敏度


荧光测温法因其无创、远程、高灵敏度和快速的温度测量能力而受到广泛关注。然而，在高温下实现卓越的灵敏度仍然是一个持续的挑战。在此，合成了一系列 Rb2−xCsxHfCl6：y%Te4+ 钙钛矿，以研究 A 位点调节对发光效率和温度响应能力的影响。Te4+ 掺杂显著提高了发光强度，软晶格内的电子-声子耦合产生了宽带黄光，由自捕获激子发射驱动。此外，A 位点调节表明，增加 Cs⁺ 含量会诱导增强的 Jahn-Teller 失真，从而提高发光效率。然而，纯 Rb 样品表现出最低的热活化能，随着温度升高，声子-激子耦合增加，缺陷活性加速了非辐射复合，从 300 K 到 390 K 将荧光寿命急剧缩短了两个数量级。利用这种卓越的热灵敏度，开发了一种基于寿命的荧光温度计，在 390 K 时获得了突破性的相对灵敏度，达到 20.69% K-1， 在多个加热和冷却循环中具有很高的可重复性。此外，还设计了用于润滑油管道的高温预警系统，展示了强大的监测能力。这项工作为开发利用卤化物钙钛矿进行高温应用的高灵敏度温度计提供了新的视角。