Bio-inspired self-healing structural color hydrogel

Significance Structural color hydrogels have been widely studied and used in different applications, such as in switches, optical devices, etc. However, because the deterioration and accumulation of damage of these materials are inevitable during applications, the creation of bio-inspired structure color materials with increased survivability is still desired for both fundamental research and practical applications. In this study, inspired by creatures in nature with spontaneous healing from injury and recovering of functionality, we demonstrated a self-healing structural color hydrogel by filling a healable protein hydrogel into an inverse opal scaffold. A series of new structural color materials with 1D linear microfiber, 2D pattern, and 3D photonic path structures could be constructed by assembling and healing the composite structural color hydrogel elements.