[ACS Nano] Promotion of Color-Changing Luminescent Hydrogels from Thermo to Electrical Responsiveness towards Biomimetic Skin Applications
writer：Shuxin Wei, H. Qiu, H. Shi, Wei Lu,* H. Liu, H. Yan, J. Zhang, P. Theato, Yen Wei, Tao Chen*
keywords：hydrogels, fluorescence, stacked graphene assembly, color changes, electrothermal effect, biomimetic skins
source：期刊
specific source：ACS Nano, 2021, inpress
Issue time：2021年
Active color-changing ability of many living species have inspired scientists to replicate the optical property into soft wet and tissue-like hydrogel materials. However, the color-changing processes of most reported examples are controlled by the traditional stimuli (e.g., pH, temperature and ions), which may suffer from the residual chemical product accumulation, and have difficulty in achieving the local control and integration into the commercial robots, especially when applied as biomimetic skins. Herein, inspired by the nervous (bio-electricity) control of skin color change in cephalopods, we present an electrically powered multicolor fluorescent hydrogel system with asymmetric configuration that couples thermo-responsive fluorescent hydrogel with stacked graphene assembly (SGA)-based conductive paper through the luminous paint as the middle layer. Owing to the highly controllable electrical stimulus in terms of amplitude and duration, the Joule heat supplied by SGA film can be regulated locally and real-timely, leading to the precise and local emission color control at low voltage. It also avoids the addition of any chemicals. Furthermore, the electrically powered color-changing hydrogel system can be conveniently integrated into the commercial robots as biomimetic skins that help them achieve the desirable camouflage, display or alarming functions.