The Smart Polymer Materials group led by Prof. CHEN Tao at the Ningbo Institute of Materials Technology and Engineering (NIMTE) of Chinese Academy of Sciences (CAS), has developed a flexible near-infrared (NIR) light-writing multicolor hydrogel system for on-demand information display. The study was published in Advanced Materials.
In the age of Internet-of-Things (IoT), the development of intelligent rewritable display systems shows great potential in alleviating the environmental pollution and resource consumption resulted from the increasing disposable electronic waste. They are promising candidate medium for the information display and transmission.
However, it remains challenging to construct such systems combining diverse functionalities, such as remote control, rapid activation, multicolor and multimode display.
The unique vertical arrangement of multilayered chromatophores contributes to the reversible and multicolor pattern display in chameleon skins. Inspired by the exquisite structure of chameleon skins, researchers at NIMTE developed a novel flexible NIR-light-triggered rewritable multicolor hydrogel system for on-demand information display.
The developed hydrogel system is in a vertically arranged multilayer structure, which consists of a fluorescent hydrogel layer as the display unit and an efficient poly(dimethylsiloxane) (PDMS)-sealed carbon nanotubes (CNTs) film layer as the control unit.
Specifically, in the fluorescent hydrogel layer, a thermo-responsive fluorescent hydrogel as inner core is constrained within a non-responsive hydrogel, thus facilitating the stable, reversible, and multicolor information loading.
By virtue of the cascading "light trigger–heat generation–fluorescence output" process, arbitrary information, like numbers and letters, could be hand-written displayed within 5 s with NIR light as a pen, and self-erased for another rewriting cycle within 36 s.
Besides the light-writing display of transient information, this bio-inspired multilayer structure design has been demonstrated to facilitate the easy patterning of both the photothermal CNTs layer and the fluorescent hydrogel display layer, realizing the sustainable light-projecting display of multicolor patterns.
This fluorescent hydrogel rewritable display system helps to meet the diverse information display or transmission requirements, improve information visualization effect and interactive experience, and may shed light on the further development of light-writing system.
This work was supported by the National Key R&D Program of China (No. 2022YFB3204300), National Natural Science Foundation of China (No. 52073297), Zhejiang Provincial Natural Science Foundation of China (No. LD22E050008), China National Postdoctoral Program for Innovative Talents (No. BX20220317), China Postdoctoral Science Foundation (No. 2022M720151) and Preferential Funding for Postdoctoral Projects in Zhejiang Province (No. ZJ2022043), Youth Innovation Promotion Association of Chinese Academy of Sciences (No. 2019297), and the Sino-German Mobility Program (No. M-0424).
Fig. Multicolor fluorescent hydrogel system with biomimetic vertical multilayer structure for on-demand information display (Image by NIMTE)
Ningbo Institute of Materials Technology and Engineering