Self-Healing Chameleon Skin Functioning in the Air Environments

Abstract

Chameleons are famous for their uncommon ability to change skin colors rapidly by tuning the lattice distance of guanine nanocrystals within the dermal iridophores. This mechanism has inspired various artificial photonic crystal (PC) films with tunable structural colors. However, the structural colors of most reported films are facile to be destroyed by external factors such as friction, impact, or water evaporation. Herein, an artificial intelligent skin, which has an elastomer–colloidal photonic crystal–hydrogel sandwich structure, is presented in this work. The outer modified polydimethylsiloxane layer acts as the cuticle to protect the hydrogel layer from water evaporation and endows the skin with self-healing ability. The inner hydrophilic hydrogel layer embedded with the colloidal photonic crystals acts as the dermis layer, and the polystyrene colloids layer plays the role of the guanine nanocrystals. A programmed color change can be easily controlled by varying the elongation of the artificial skin, covering the full visible spectrum range. Moreover, skin with patterned stripes, which is similar to the panther chameleon skin that can manipulate multiple colors, has also been achieved. The present artificial skin will offer fresh perspectives on the preparation of artificial chameleon skin similar to the real dynamic flexible skin, which would promote the application of PCs in optical devices.