Carboxymethyl chitosan-gelatin-based self-adhesive hydrogels for zinc ion hybrid supercapacitors and multifunctional sensors

Recent advances in flexible electronics technology have heightened demand for safe, long-life energy storage devices. This paper employs a functionally oriented and component-synergistic approach to design and prepare multifunctional hydrogel electrolytes (HEs) for constructing long-life flexible zinc-ion hybrid supercapacitors (ZHICs). The study utilized biomass gelatin as a scaffold, incorporating carboxymethyl chitosan (CMCs) and zwitterionic materials to form a physicochemical dual network. This approach constructed a multi-layered dynamic bonding network, endowing the hydrogel with self-adhesive and self-healing intelligent properties, significantly enhancing its mechanical strength and electrical conductivity. Ultimately, sodium alginate (SA) was incorporated to confer 2D printing adaptability, successfully identifying the optimal formulation composite hydrogel as the printing ink. The introduction of SA enabled the composite hydrogel to form a stable, interpenetrating network with both rigidity and toughness, exhibiting high mechanical properties (toughness is 100 MJ m −3 ), zinc plate interfacial adhesion energy is 13.96 J m −2 , alongside self-healing capabilities upon injury (10 min self-healing rate: 22.3%). Rapid ion-crosslinked HEs formed by immersing composite hydrogels in Zn 2+ solutions exhibit a conductivity of 0.34 S m −1 . The ZIHCs devices assembled from HEs have a thickness of 2 mm, operate stably under certain pressure and temperature variations, and demonstrate stable cycling characteristics exceeding 11,000 cycles. This research provides inspiration for designing flexible hydrogel electrolytes with excellent environmental adaptability.