Bioinspired Color-Changeable Organogel Tactile Sensor with Excellent Overall Performance

Abstract

Inspired by chameleons’ structural color regulation capability, a simple, but effective, swelling method is proposed for the first time to prepare an ionic polyacrylamide (PAAm) organogel for simultaneous tactile sensing and interactive color changing. The PAAm organogel obtained by swelling the PAAm scaffold in the dimethyl sulfoxide solution of organic electrochromic material (OECM) shows an extremely large stretchability with an elongation of 1600%, a supersoftness with a compressive modulus of 7.2 kPa, an excellent transmittance up to 90%, and a very fast response time of 0.5 s combined with the characteristic of interactive color changing. The PAAm organogel also suggests a universal design ability to tailor coloration spectra for tactile sensors via simply changing the type and content of OECM. The tactile sensor based on a PAAm organogel is capable of serving as a wearable device for precisely tracing human body motion performance and directly visualizing the stress distribution via interactive color changing capability. It is demonstrated that the swelling method proposed here is a simple and practical strategy to prepare ionic organogels with both piezo-resistive and electrochromic effects.

Solution‐Processed Stretchable Ag2S Semiconductor Thin Films for Wearable Self‐Powered Nonvolatile Memory

“…Recently, significant progress has been made toward the development of stretchable insulators and conductors, including polymeric dielectrics, metal nanowire, and conjugate polymer composites. [ 8–12 ] However, finding candidates of stretchable semiconductors that have an appropriate bandgap and related electrical performance as well as mechanical and environmental durability has been challenging. [ 13,14 ] For instance, conventional inorganic semiconductors held by ionic or covalent bonds are intrinsically brittle and show only the strain of about 0.1–0.2%, [ 15–17 ] thus easily experiencing mechanical cracks due to the accumulation of fatigue under repetitive deformation, while organic‐based semiconductors are vulnerable to humidity, oxygen, and chemical and thermal stresses, and their inferior electrical properties; [ 18–21 ] therefore, they cannot fulfil the criteria for future deformable semiconductor devices.…”

Panther chameleon-inspired, continuously-regulated, high-saturation structural color of a reflective grating on the nano-patterned surface of a shape memory polymer

“…1D), which is much lower than the results in the references. [41][42][43][44][45][46][47][48] The lower magnitude of the FWHM, resulting from a 1-D grating and the monodispersed size of nano-stripes (Scheme 1), indicates a structural color with higher saturation.…”

“…In recent years, stimuli-responsive structural colors have been paid much attention. [21][22][23][24][25][26][27][28][29][30][31][32] Inspired by the ability to change the skin color during male contests or courtship of panther chameleons, some strategies have been developed to adjust the periodic structures aer their preparation. Yang et al prepared photonic crystals in shape memory polymers (SMPs) by selfassembling silica particles in a polymer matrix and the subsequent removal of silica colloids by wet etching.…”

Centrosymmetric‐ and Axisymmetric‐Patterned Flexible Tactile Sensor for Roughness and Slip Intelligent Recognition

“…Moreover, these can only qualitatively describe the state of tension, pressure, and bending, and cannot quantitatively determine the magnitude and direction of the shear force required by existing robots. [ 18,37–40 ] As a result, key information (e.g., static friction and sliding friction) cannot be decoded, making it difficult to realize the dexterous operation of robots through physical feedback and sensations that correspond to interactions with the environment. [ 41 ]…”