Abstract Mechanoluminescence (ML) is generated during exposures of certain materials to mechanical stimuli. Many solid materials produce ML during their fracturing, however, the irreversibility of fracto-induced ML limits the practical applications of these materials. In 1999, Chao-Nan Xu discovered an intense and reproducible ML from trap-controlled materials, including ZnS:Mn2+ and SrAl2O4:Eu2+, and introduced the principles and applications of hybrid inorganic/organic mechanoluminescent (ML) composites, and related sensors to visualize stress/strain in target structures. This discovery has triggered intense research interest in trap-controlled ML materials and composites over the past 2 decades. Notable achievements of this research include the development of trap-controlled materials that exhibit bright ML emission from the ultraviolet to the near infra-red, and multiscale mechano-optical sensitivities. This research has also increased our understanding of the mechanisms of ML phenomena, enabling the rational design of trap-controlled ML materials. Practical applications of ML are also being driven by the discovery that ML composites can serve as “mechano-optical sensitive skin” for structural health diagnosis, stress sensors for biomechanics, and mechanically-activated light sources. This review focuses on the design, synthesis, characterization, optimization and application of trap-controlled ML materials, and concludes with discussions on future directions of ML research and specific challenges to improve ML materials for real-world applications.

中文翻译：

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陷阱控制的机械发光材料

摘要 机械发光 (ML) 是在某些材料暴露于机械刺激过程中产生的。许多固体材料在其压裂过程中会产生 ML，然而，压裂诱导 ML 的不可逆性限制了这些材料的实际应用。1999 年，Chao-Nan Xu 从陷阱控制材料（包括 ZnS:Mn2+ 和 SrAl2O4:Eu2+）中发现了强烈且可重复的 ML，并介绍了混合无机/有机机械发光 (ML) 复合材料的原理和应用，以及相关的传感器可视化目标结构中的应力/应变。在过去的 20 年里，这一发现引发了对陷阱控制的 ML 材料和复合材料的强烈研究兴趣。这项研究的显着成就包括开发出从紫外到近红外的明亮 ML 发射和多尺度机械光学灵敏度的陷阱控制材料。这项研究还增加了我们对 ML 现象机制的理解，从而能够合理设计陷阱控制的 ML 材料。ML 的实际应用也受到以下发现的推动：ML 复合材料可以作为用于结构健康诊断的“机械光学敏感皮肤”、用于生物力学的压力传感器和机械激活光源。本综述侧重于陷阱控制的 ML 材料的设计、合成、表征、优化和应用，