Interactive and responsive materials are dynamic molecular systems that are capable of modulating their behavior and adapting to environment autonomously. Photochromic materials are among the fascinating class of dynamic responsive systems and widely used in molecular switches and optoelectronic devices. However, the phototriggered color changing largely relies on the conformation transformation of the photochromic motif, which significantly limited their usage in organic liquid solutions. Herein, we demonstrate a photochromic organic supramolecular system by using electron-rich N,N-dimethylacetamide (DMA) and electron-deficient naphthalenediimide (NDI) as a donor and acceptor, respectively. In the binary system, the photo-induced electron transfer through lone pair···π interactions pathway leads to dynamic photochromic response not only in the solution but also in the crystalline aggregated state. Furthermore, by incorporating the supramolecules in the polymer matrix, the transparent polymeric film also exhibits rapid photochromic response, which makes it a promisingly interactive and adaptive photochromic material.
Jun Xu,Tinghui Zhu,Xiangzhen Chen,Dan Zhao,Yongxin Li,Lina Zhang,Ning Bi,Jian Gou,Lei Jia
Integrating multiple signals with different excitation wavelength dependence and temperature response properties into a single nanomaterial to construct multimodal anti-counterfeiting materials is still challenging. In this research, an exciting lanthanide hybrid tri-channel tubular anti-counterfeiting nanomaterial was fabricated by fixing NaYF 4 :Yb 3+ /Tm 3+ up-conversion nanoparticles and Cit-Eu-TC complex on the surface of YHF:Ce/11.4%Tb nanotubes , which can be further used to make anti-counterfeiting fluorescent ink and hydrogel. The hidden three-mode anti-counterfeiting patterns showed bright green, red, and blue-violet fluorescence under 254 nm, 365, and 980 nm excitation, respectively. More importantly, under the co-irradiation of 254 and 365 nm light, the patterns prepared by the anti-counterfeiting ink showed mesmerizing dynamic anti-counterfeiting performance under the stimulation of developer and temperature. With the developer's dosage increase or temperature change, the color of anti-counterfeiting patterns changed obviously. The combination of this dynamic stimulus-responsive anti-counterfeiting feature and the above three-channel static anti-counterfeiting feature might bring about multi-mode static-dynamic anti-counterfeiting performance, significantly improving the difficulty of forgery and was expected to be widely used in the field of confidential information and file anti-counterfeiting.
危险品化学品经营许可证（带存储）