A self-powered thermogalvanic organohydrogel-based touch-to-speech Braille transmission interface with temperature resistance and stretchability

Human-machine interaction has made a great advance in Braille information communications, enabling the interactions between visually impaired people, normal people, and auxiliary devices. Herein, a thermogalvanic organohydrogel electrolyte (OHE) was fabricated via a facile freezing-thawing route with Sn2+/Sn4+ as a redox couple and NaCl as an additional electrolyte, which demonstrates a favorable mechanical and thermoelectric performances with a high Seebeck coefficient of −1.62 mV/K. Owing to the intense hydrogen bonds between water and DMSO, the OHE manifests anti-freezing, non-drying properties and a wide working temperature range (−20 to 60 °C), thus sustaining a stable output performance in harsh surroundings. Considering the well-designed comprehensive performance, the OHE was further integrated into a self-powered Braille transmission interface that can easily convert regular touches into visual text and auditory feedback, realizing self-powered real-time Braille transmission and readout for the first time. The strategy of applying the OHE to a phonic Braille transmission interface reveals the considerable possibilities of heat-to-electricity conversion in information transfer and human-computer interaction.