Highly robust cellulose photonic hydrogels with reconfigurability and mechanochromism

Abstract

Biomimetic Bouligand structures hold transformative potential for developing high-performance nanocomposites in cutting-edge fields, ranging from bioplastics and architecture to aerospace. Despite the remarkable precision of the self-assembly strategy, they often function as inert substrates lacking active interfibrous and their biomimetic derivatives exhibit low ductility and insufficient toughness. Here we present robust and photonic Bouligand structural hydrogels with dynamic mechanochromic properties, achieved by reorienting the chiral nematic structures through crystallization domain reduction and chain reconstruction. These hydrogels demonstrate exceptional mechanical performance (ultrahigh stretchability of over 950 % and toughness up to 155.5 MJ∙m⁻³). Furthermore, the photonic hydrogel demonstrates a reversible color change with a wavelength shift of 427 nm, alongside progressive electrical sensing that remains responsive across a broad range of mechanical stretching. This innovative approach and resulting photonic Bouligand hydrogel offer significant potential for smart photonics and pave the way for practical applications of these sustainable photonic cellulose materials.