Photoswitchable and Reversible Fluorescent Eutectogels for Conformal Information Encryption

Abstract

Smart fluorescent materials that can respond to environmental stimuli are of great importance in the fields of information encryption and anti‐counterfeiting. However, traditional fluorescent materials usually face problems such as lack of tunable fluorescence and insufficient surface‐adaptive adhesion, hindering their practical applications. Herein, inspired by the glowing sucker octopus, we present a novel strategy to fabricate a reversible fluorescent eutectogel with high transparency, adhesive and self‐healing performance for conformal information encryption and anti‐counterfeiting. Using anthracene as luminescent unit, the eutectogel exhibits photoswitchable fluorescence and can therefore be reversibly written/erased with patterns by non‐contact stimulation. Additionally, different from mechanically irreversible adhesion via glue, the eutectogel can adhere to various irregular substrates over a wide temperature range (−20 to 65 °C) and conformally deform more than 1000 times without peeling off. Furthermore, by exploiting surface‐adaptive adhesion, high transparency and good stretchability of the eutectogel, dual encryption can be achieved under UV and stretching conditions to further improve the security level. This study should provide a promising strategy for the future development of advanced intelligent anti‐counterfeiting materials.

Supramolecularly Connected Armor-like Nanostructure Enables Mechanically Robust Radiative Cooling Materials

“…The spectra of hydrogenbonded −OH groups and −C�O groups indicate that the hydrogen bonds between CNFs and PAAS are gradually broken with the increase of temperature (Figure S5, Supporting Information). 28,29 These results strongly suggest that the breakage of hydrogen bonds of related groups leads to new "free" groups generation. Moving-window two-dimensional correlation spectra (PCMW2D) (Figure S5d−l) were further performed to investigate the accurate disassociation temperature of hydrogen bonds in TMCP.…”

Dynamic Fluorescence Materials Based on Naphthalimide-Functionalized Silica Aerogels and Applications in Advanced Information Encryption

“…Within the supply chain, the huge economic losses caused by counterfeiting and fraudulent activities not only damage the reputation of enterprises but also pose a major threat to the safety of consumers. Therefore, in the field of production, manufacturing, and sales, the application of the anticounterfeiting technology is becoming more and more obvious. − Common anticounterfeiting technologies include laser-based authentication, QR code verification, nanotechnology-based security features, chemical anticounterfeiting measures, fluorescent anticounterfeiting, and so on. Among these, fluorescent anticounterfeiting materials are widely explored because of their remarkable visibility, multilayer protection, and user-friendliness, which provide powerful anticounterfeiting measures for commodities and documents. − However, most fluorescent anticounterfeiting materials are based on their static features or signals, which greatly limits the encryption of advanced information. , In view of this, materials that can be switched to multiple states under external stimuli as needed would be promising candidates.…”

“…Therefore, in the field of production, manufacturing, and sales, the application of the anticounterfeiting technology is becoming more and more obvious. 1−4 Common anticounterfeiting technologies include laser-based authentication, 5 QR code verification, 6 nanotechnology-based security features, 7 chemical anticounterfeiting measures, 8 fluorescent anticounterfeiting, 9 and so on. Among these, fluorescent anticounterfeiting materials are widely explored because of their remarkable visibility, multilayer protection, and user-friendliness, which provide powerful anticounterfeiting measures for commodities and documents.…”

Modified Sodium Alginate for Degradable Supramolecular Plastic with High Mechanical Strength

“…The global demand for plastic products which are considered essential in daily life results in an annual production of a huge amount of plastics (exceeding 380 million tons) [1–5] . However, due to the non‐degradability, these plastics pose a great threat to the ecological environment and may even endanger human's health or animal's life [6] .…”