Materials exhibiting reversible changes of their photoluminescence properties upon exposure to heat have an immense potential in various advanced photonic applications. Particularly, the control over an on‐demand response of thermochromic luminescent materials (TLMs) similar to a chameleon is of great importance. However, it is still difficult and challenging to achieve it. Therefore, this paper reports a simple and effective way to construct TLMs, which involves the incorporation of the metal–ligand complexes into polyethylene glycol (PEG). Ratiometric or off–on response modes of these TLMs can be tuned by incorporating metal complexes based on either Zn²⁺ or Co²⁺ into PEG and by taking advantage of reversible metal–ligand coordination, dissociation, or excited‐state conformation changes of the resulting materials. Moreover, by choosing PEG matrices with different molecular weights, the thermochromic transition temperatures of these TLMs can be tuned. It is also demonstrated that the controllable response behavior of these chameleon‐like TLMs can be used in applications related to real‐life anti‐counterfeiting and security printing. This work opens novel opportunities for the development of smart materials with controllable responses useful for advanced photonic applications.

中文翻译：

---

具有可控响应特性的变色龙类热致变色发光材料，用于多层安全印刷

暴露于热中后其光致发光特性发生可逆变化的材料在各种先进的光子应用中具有巨大的潜力。特别是，控制类似于变色龙的热致变色发光材料（TLM）的按需响应非常重要。然而，实现它仍然是困难和挑战的。因此，本文报道了一种构建TLM的简单有效的方法，该方法涉及将金属-配体络合物掺入聚乙二醇（PEG）中。可以通过结合基于Zn ²⁺或Co ^2+的金属配合物来调整这些TLM的比例响应或关闭响应模式进入PEG，并利用所得材料的可逆金属-配体配位，解离或激发态构象变化进行转换。此外，通过选择具有不同分子量的PEG基质，可以调节这些TLM的热致变色温度。还证明了这些变色龙类TLM的可控响应行为可用于与现实生活中的防伪和安全打印有关的应用程序中。这项工作为开发具有可控响应的智能材料提供了新的机遇，这些材料可用于高级光子应用。