Enhancing Electrochemical Performance of Zinc-Air Batteries Using Freeze Crosslinked Carboxymethylcellulose-Chitosan Hydrogels as Electrolytes

Abstract

Zinc-air batteries (ZABs) are of great interest as a replacement option for subsequent technologies to lithium-ion batteries. Still, the need for suitable electrolyte materials limits their application in commercial devices. In this study, a green hydrogel composed of chitosan and carboxymethylcellulose was synthesized with the use of citric acid as a chemical crosslinker, physical freezing-thawing, and freezing-drying strategies. Physicochemical, thermal, and electrochemical characterizations were performed to study the effects of the proposed synthesis' on the performance of the hydrogels for the desired application. The obtained hydrogels showed a porous morphology that was doped with a 12 M KOH solution. Adequate complexation of K+ cations and the polymer chains was observed. The resulting membranes showed an enhanced ionic conductivity of 0.39 S cm‒1, attributed to the pores and channels generated by the crosslinking strategies, contributing to the pathways for ions to move easily. In addition, the temperature dependence of the conduction mechanism was confirmed in the temperature range of 0 to 70°C. The electrolytes were employed in ZABs prototypes, achieving maximum power density of 117 mW cm‒2 and specific capacitance of 1899 mAh g‒1. The presented results show the promising properties of these hydrogels as electrolytes for green storage devices.

Green Energy Storage: Chitosan-Avocado Starch Hydrogels for a Novel Generation of Zinc Battery Electrolytes

“…It can be inferred that the amino groups of chitosan have contributed to this shift. Compared with its counterpart, the membranes synthesized using the casting method [22], there is a noticeable difference in the intensity of the C-O-C stretch bond vibrations when immersed in the ionic solution due to the freeze-thaw techniques proposed by the synthesis method [40,41].…”

Chitosan-based hydrogels: From preparation to applications, a review

“… Gram-positive bacteria are inhibited. boost cell growth and has strong thermal and mechanical qualities ( Lin, Lo, Tseng, Liu, Shih, & Cheng, 2019 ) Chitosan-based isothiocyanatotrimellitic anhydride cross-linked hydrogels Br12 dye, chitosan, isothiocyanatotriphthalic anhydride Chemical crosslinking Isothiocyanatotrityltriphthalic anhydride Treatment of BR − 12 Dyes Highly Effective Alternative Adsorbents The extremely strong adsorption capacity for BR dyes ( Mohamed, Al-Harby, & Almarshed, 2021 ) PC/CS （PCCS）hydrogels Chitosan hydrochloride, carboxylated polyvinyl alcohol (PC), succinic anhydride, triethylamine (TEA) Chemical cross-linking (amidation reaction) Carboxy polyvinyl alcohol (PC) Adhesive dressings for dynamic traumatic wounds Good self-healing ability, strong adhesion, and antimicrobial ability; good cytocompatibility and hemostatic properties ( Liu et al, 2023 , Liu et al, 2023 ) BC-Ch Hydrogel Genipin, chitosan, bacterial cellulose (BC) Chemical crosslinking Genipin Drug carrier Controlled drug release capability and swelling behavior ( Arikibe, Lata, Kuboyama, Ougizawa, & Rohindra, 2019 ) Frozen-Thawed CMC-CS-CA hydrogels Chitosan, carboxymethyl cellulose sodium salt, Chemical and physical cross-linking (hydrogen bonding interactions, electrostatic interactions) Citrate A device for green storage of electrolytes Improved ionic conductivity for better discharge performance ( Bósquez-Cáceres, Bejar, Álvarez-Contreras, & Tafur, 2023 ) Hierarchical microCS hydrogel scaffold Chitosan powder, LiOH, epichlorohydrin (ECH) Chemical crosslinking Epichlorohydrin Stents mimicking the dura mater High mechanical strength and degradation rate, promotes cell proliferation, good cytocompatibility ( J. Wang et al, 2021 ) (CS-PEG-HA) hybridized hydrogels Methacrylic anhydride and dibenzocyclotitani- peg4 - hydroxy succinimide ester (dbco - peg4 - nhss -ester), chitosan, 4-arm PEG-azide (2 KDa), 1-(3-dimethyl aminopropyl)-3-ethyl carbodiimide hydrochloride Chemical crosslinking Polyethylene glycol, methacrylic anhydride Novel materials to accelerate wound healing in ...…”