A highly-proton conductive poly(vinyl alcohol)/silica nanocomposite membrane for PANI@GNP symmetric supercapacitor separator

• Published in: Journal of energy storage 2024-12, Vol.104, p.114615, Article 114615
• Main Authors: Zhang, Jiawen, Zhu, Aiping
• Format: Article
• Language: English
• Subjects: PANI@GNP electrode; Proton based supercapacitor; Proton transport channel; Separator membrane
• ISSN: 2352-152X
• DOI: 10.1016/j.est.2024.114615

Polyaniline (PANI) has potential as an anode and cathode for proton based batteries (PBs) owing to its high energy density (295 mAh g−1) and excellent reversible redox activity. Achieving proton electrolytes with fast single-proton conduction behavior, separator-required mechanical properties and good proton transport channel is essential but extremely challenging for the practical success of PBs. Herein, this proton separator is constructed with nano-silica grid points in polyvinyl alcohol (PVA) chains cross-linked by sulfuric acid. Results show that PVA/inorganic composite proton membrane (PIC-PM) can immobilize the sulfate anions and help dissociate H+, which leads to a high ionic conductivity (8.6 × 10−2 S cm−1). Moreover, PIC-PM shows enough toughness and mechanical strength to puncture resistance. When the PIC-PM was applied to assemble a PANI@GNP symmetric supercapacitor, it delivers a high capacity of 943.1 F/g at 0.5 A/g; a rate capability of 74.9 % with the current density increasing from 0.5 to 5 A/g; and a capacity retention rate of 84.3 % after 1000 cycles in a current density of 3.5 A/g. •PVA-efSiO2/H2SO4 separator has decent mechanical property.•PIC-PM has unique organic inorganic cross-linked network structure.•PIC-PM makes symmetric PANI@GNP supercapacitor deliver a high capacity of 943.1 F/g.•The stable proton channel on the “O” of cross-linked network with 8.7 wt% bond water