Hybrid Cu(I)-based halides possess significant potential in optical anti-counterfeiting due to their diverse crystal structures and unique optical properties. Nevertheless, the synthesis of multi-optical mode responsive hybrid Cu-based halides remains a formidable challenge for achieving high-security optical encryption. Herein, two hybrid Cu-based halides featuring distinct [Cu₂I₄]²⁻ and [Cu₄I₆]²⁻ inorganic units, namely (MePPh₃)₂Cu₂I₄·DMF and (MePPh₃)₂Cu₄I₆ (MePPh₃⁺ = C₁₉H₁₈P⁺), are obtained through solvent volatilization. The colorless (MePPh₃)₂Cu₂I₄·DMF crystals exhibit cyan emission upon UV light irradiation, whereas the yellow (MePPh₃)₂Cu₄I₆ crystals emit vivid yellow photoluminescence under either UV or blue light. Furthermore, the structural transformation from (MePPh₃)₂Cu₂I₄·DMF to (MePPh₃)₂Cu₄I₆ can be triggered by ethanol, inducing changes in both the visual crystal color and luminescence color, thus showcasing a dual-optical mode response. Benefiting from these unusual properties, optical anti-counterfeiting and information encryption systems are constructed based on these hybrid metal halides. This work not only enriches the stimulus-responsive hybrid halide family, but also provides a novel platform for multifaceted applications in advanced anti-counterfeiting and information encryption.

中文翻译：

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多刺激双光模式响应式混合卤化铜 （I） 用于高级防伪和信息加密


由于其多样化的晶体结构和独特的光学特性，杂化 Cu（） 基卤化物在光学防伪方面具有巨大潜力。然而，多光模式响应式混合 Cu 基卤化物的合成仍然是实现高安全性光加密的巨大挑战。本文中，两种杂化铜基卤化物具有不同的 [Cu₂I₄]²⁻ 和 [Cu₄I₆]²⁻ 无机单元，即 （MePPh₃）₂Cu₂I₄·DMF 和 （MePPh₃）₂Cu₄I₆ （MePPh₃⁺ = C₁₉H₁₈P⁺） 是通过溶剂挥发获得的。无色 （MePPh₃）₂Cu₂I₄·DMF 晶体在紫外光照射下呈青色发射，而黄色 （MePPh₃）₂Cu₄I₆ 晶体在紫外光或蓝光下发出鲜艳的黄色光致发光。 此外，（MePPh₃）₂Cu₂I₄·DMF 到 （MePPh₃）₂Cu₄I₆ 可由乙醇触发，引起可见晶体颜色和发光颜色的变化，从而表现出双光模式响应。受益于这些不寻常的特性，基于这些混合金属卤化物构建了光学防伪和信息加密系统。这项工作不仅丰富了刺激响应的杂交卤化物家族，而且为高级防伪和信息加密的多方面应用提供了一个新的平台。