All-Starch-Based Hydrogel for Flexible Electronics: Strain-Sensitive Batteries and Self-Powered Sensors

Natural biopolymers are biodegradable and biocompatible thus have huge potential for the development of biomedical or transient systems. Herein, we report an entirely starch-based hydrogel flexible electronics including strain-sensitive batteries self-powered (SP) wearable sensors. This is only based on natural high-amylose starch, CaCl2, glycerol, preparation method green facile (namely, stirring at 70 °C 1 h). highly stretchable, flexible, reprocessable, self-healable. Based this hydrogel, developed a galvanic cell-type Zn–Cu battery (composed one additionally incorporated with zinc powder other CuCl2 copper powder), which has voltage 0.81 V its output current positively correlated compression deformation. battery, sensor was further constructed, high sensitivity (1.5371 kPa–1) even under weak stress. SP can be used to detect human activities involving small strain such as wrist pulse throat vibration, signals strong, clear, stable. Considering easy processability, cost-effectiveness, sensitivity, robustness, greenness electronics, their brilliant application prospect foreseen.