Impact of ammonium thiocyanate on the thermal and conductive properties of honey-enhanced biopolymer electrolytes for electrochemical capacitors

Abstract

In today’s world, the escalating demand for power necessitates the expansion of renewable energy sources. Electrochemical double-layer capacitors (EDLCs) offer a promising solution to this challenge. Biopolymers are emerging as sustainable and high-performance materials for EDLC development. This work introduces a novel biopolymer electrolyte for EDLCs, comprising chitosan (Ch)-dextran (Dx) as the polymer host, ammonium thiocyanate (NH4SCN) as the ionic species, and honey as a natural plasticizer. Thermogravimetric analysis (TGA) confirms that honey and dopant salt enhance electrolyte thermal stability. Furthermore, the glass transition temperature (Tg) of the Ch-Dx blend decreases from 148.40 °C to 97.87 °C with the incorporation of 10 wt% honey, indicating an increased amorphous region in the polymer host. The EDLC with the honey-based electrolyte exhibits a significantly higher single electrode specific capacitance (Csp) of 97.48 F g−1 compared to the electrolyte without honey (42.01 F g−1) at a scan rate of 1 mV s−1. GCD analysis also reveals a higher Csp of 50.41 F g−1 for the EDLC with the honey-added electrolyte, compared to 21.66 F g−1 for the EDLC without honey.