Electrochemical Behavior of Clay-Based Nanocomposites in an Ion-Exchange Gel Membrane for Supercapacitor Applications
Borislava Mladenova, Gergana Ivanova, Antonia Bakalova, Elefteria Lefterova, Antonia StoyanovaThe development of low-cost, environmentally friendly, and electrochemically stable electrode materials remains a significant challenge for supercapacitors. In the present study, composite materials based on a montmorillonite K10 clay support were synthesized and characterized. Coconut shell-derived activated carbon, manganese dioxide (MnO2), and/or activated carbon (YP-80F) modified with silver nanoparticles were utilized as functional additives to the clay matrix. The aim of this work is to enhance the specific capacitance and electrochemical stability of the materials through a synergistic effect between these individual components. The novelty of this study lies in the integration of montmorillonite K10-based nanocomposites with an ion-exchange hydrogel membrane and in the investigation of the synergistic effects of different functional additives on the electrochemical performance of supercapacitors. The electrodes were fabricated using a casting method, while a commercial membrane, pre-soaked in a sodium sulfate solution, was employed as both separator and electrolyte. The membrane functions as an ion-exchange hydrogel, contributing to high ionic conductivity and reduced interfacial resistance. The electrochemical results indicate that the presence of additives significantly improves electron transport within the system, while the K10 clay support acts as a stable structural framework. The obtained results demonstrate the potential of clay-based nanocomposites integrated into gel-polymer systems for the development of efficient, low-cost, and environmentally friendly next-generation supercapacitors.