Transparent, Stretchable, and Recyclable Triboelectric Nanogenerator Based on an Acid- and Alkali-Resistant Hydrogel

Self-powered sensors based on triboelectric nanogenerators (TENGs) had attracted great attention in the field of wearable electronics due to their high sensitivity, flexibility, and no need for external power supplies. However, current wearable devices were easy to be corroded and damaged in harsh environments and were difficult to recycle and reuse, which not only posed a huge challenge to long-term use but also polluted the natural environment. Here, a transparent, stretchable, and recyclable triboelectric nanogenerator (R-TENG) based on acid–alkali-resistant hydrogels had been designed. The prepared polyacrylamide-β cyclodextrin-sodium chloride hydrogel (PAAm-βCD-NaCl hydrogel) as the electrode of R-TENG could effectively resist strong acid and alkali. In addition, the swelling properties of hydrogel were applied to a nanogenerator for the first time so that the first recyclable triboelectric nanogenerator was fabricated, which could be reused after dehydration. R-TENG could not only be used as an energy device but also as a strain sensor to monitor human motion, which showed that R-TENG had great application prospects in harsh environments and flexible wearable fields.