Self-adhesive frost-resistant conductive hydrogel electrolytes based on TA@WSCA-Zn autocatalytic system for flexible and foldable solid-state capacitors

In this study, we have successfully prepared a freeze-resistant conductive hydrogel with a fast polymerization rate and excellent mechanical and adhesive properties. In this paper, hydrogels capable of rapid polymerization in a short time were prepared based on the TA@WSCA-Zn (WSCA, water-soluble cellulose acetate; TA@WSCA, tannic acid-coated WSCA suspension; TA@WSCA-Zn, a certain amount of zinc chloride (ZnCl2) was added to TA@WSCA suspension;) autocatalytic system at room temperature or low temperature. TA@WSCA-Zn forms a stable reversible quinone-catechol redox reaction to activate the decomposition of ammonium persulfate (APS, initiator) to produce SO4- radicals, which triggers the ultra-fast polymerization of amphoteric ([2-(methacryloyloxy) ethyl] dimethyl-(3-sulfopropyl), SBMA) and acrylic monomers (AA). To improve the frost resistance and electrical conductivity of the hydrogels, we also introduced amphoteric ions, which can provide migration channels for Zn2+ and greatly increase the migration rate. The TA@WSCA-7.5/PSA hydrogel (PSA, hydrogel prepared by polymerization of acrylic acid and SBMA as monomers;) can achieve tensile strength and toughness of 1.33 MPa and 4.89 MJ m(-3). It can provide excellent electrical conductivity and interfacial adhesion over a temperature range of 25 to 60 degrees C. In addition, the supercapacitor assembled from the TA@WSCA-7.5/PSA hydrogel electrolyte still has good capacitance characteristics after folding and 10,000 charge/discharge cycles, with a capacitance retention of 93.33 % and an excellent cycle life. This autocatalytic system provides a new strategy and approach for the preparation of freeze-resistant conductive hydrogel electrolytes.

Automated summary

In this study, a freeze-resistant conductive hydrogel with fast polymerization rate, excellent mechanical and adhesive properties was successfully prepared. Hydrogels capable of rapid polymerization were prepared using the TA@WSCA-Zn autocatalytic system at room temperature or low temperature. The introduction of amphoteric ions greatly improved the frost resistance and electrical conductivity of the hydrogels. The supercapacitor assembled from the hydrogel electrolyte showed good capacitance characteristics and cycle life after folding and 10,000 charge/discharge cycles. This autocatalytic system provides a new strategy and approach for the preparation of freeze-resistant conductive hydrogel electrolytes.