Piezoelectric cellulose/poly(vinylidene fluoride) glycerogels with synergistically enhanced energy output for wide temperature range

Abstract

Gel-based piezoelectric materials are stretchable, wearable, and environmentally friendly, unlike their conventional solid counterparts. However, designing environment-tolerant, high-performance piezoelectric gels is challenging. Herein, we develop a piezoresponsive stretchable glycerogel (GG), leveraging the cooperative structure-forming effect of cellulose, poly(vinylidene fluoride) (PVDF) and glycerol (a green extremotolerant solvent). The facile inter- and intramolecular cellulose/PVDF interactions within the hydrogen-bonded network of glycerol generate a highly electroactive crystalline β-phase while retaining mechanical integrity. Therefore, the synergy-driven GG is more piezoresponsive than gels fabricated using individual polymers. Despite having a low polymer density (≈16 wt%), the GG exhibits impressive functional attributes such as Young’s modulus (≈12 MPa), tensile strength (≈3 MPa), piezoelectric voltage (92 mV cm^-2), and current output (110 nA cm^-2). Furthermore, it exhibits long-term stability over a wide temperature range (-20 to 80 °C) owing to its robust structural integrity and thermal adaptability. The study findings underscore the viability of preparing high-performance extremotolerant piezoelectric gels for use in next-generation stretchable/wearable piezoelectric sensors and energy devices.

Keywords

Piezoelectric gels / cellulose / poly(vinylidene fluoride) / glycerogels / synergistic effect / wide temperature applicability

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