Study of triazine-based-polyimides composites working as gel polymer electrolytes in ITO-glass based capacitor devices

Two novel gel polymer electrolytes (GPEs) systems using triazine-based-polyimides (TPIs) working as both oxidizing and reducing dopants in the capacitors were prepared in this paper. Due to the advantages of highly flat surface of ITO glass electrodes, sandwich devices made of ITO as electrode material can be regarded as typical representatives of the double-layer capacitor. According to the results fitting with the modified Randles model, all chi squared values were lower than 1%. Cyclic voltammetry (CV) method and electrochemical impedance spectroscopy (EIS) method are introduced to explore the change of Faraday capacitance occurred on the electrode/electrolyte interface, as well as the transportation and diffusion of carriers on the electrode/electrolyte interface. The results of CV reveal that when the added TPI-1 concentration reaches 22mg/mL, the REDOX peaks reach the maximum. The results of EIS show that when the concentration of TPI-2 was 2.8mg/mL, the Warburg impedance value was only 30.3% of that of the original polymethyl methacrylate gel system. The results convincingly indicate the contribution of TPI-1 to the capacitance, and contribution of TPI-2 to the impedance in the GPEs, which demonstrated the extensive potential application of TPIs in GPEs materials.