Transparent, Robust, Nondrying, and Antifreezing Cellulose Organohydrogels for Energy Harvesting and Sensing Applications

Transparent and robust cellulose organohydrogels with nondrying and antifreezing properties were fabricated, by soaking cross-linked cellulose in glycerol/NaCl/H2O solution, inspired by the cryopreservation of biological samples. The organohydrogel possessed robustness, with tensile strength and elongation at break reached 6.8 MPa and 220%, respectively, superior than most of the reported cellulose hydrogels. Glycerol endowed cellulose organohydrogels with excellent antidrying properties and low temperature tolerance down to −63.7 °C, among the top class of hydrogels with the same kind. The cellulose organohydrogel demonstrated potential applications in the fields of energy harvesting as well as sensing. Cellulose organohydrogels based triboelectric nanogenerator (TENG) was capable of outputting alternative electricity with an instantaneous peak power density of 315 mW m–2, superior to most of the reported TENGs with an ionic conductor. In addition, the resistive and piezo-capacitive sensors based on cellulose organohydrogel demonstrated fast response, reliability, and stability to strain and pressure, at both room temperature and subzero temperature. The present work expanded the potential application of cellulose in the fields of energy harvesting and multifunctional sensors.