Molar conductivity and ion transport behaviour of kappa carragenaan (K-CAR)-licl biopolymer electrolytes at varying temperatures

The limiting molar conductivity (Λ⁰) and ion transport behavior of a kappa-carrageenan (κ-car) and lithium chloride (LiCl) in aqueous medium biopolymer electrolyte system at various temperatures 25 °C-50 °C and polymer concentrations (Cpoly) of 1.0x10-3 1g/cm³ - 3.0x10-3 g/cm³ are measured for a range of salt concentration of 1.00x10⁻4 to 2.821x10-8 mol/cm3 using a simple AC conductivity meter connected with its electrode. The Λ⁰ for each system is determined after the Kohlrausch equation. The results show that the Λ⁰ increases with temperature, indicating ion pairing happened, decreases salt dissociation (α), and increase ion-ion association. As the polymer concentration increases, a decreasing trend in conductivity is observed due to the restriction of ion movement and stronger ion-polymer interactions. Enhanced interactions between polymer and salt in the κ-car/LiCl system contribute to better ionic conductivity response with temperature. The activation energy (Ea) of the system is calculated using the Arrhenius equation, supporting the temperature-dependent conductivity behavior. These findings contribute to the advancement of eco friendly biopolymer electrolyte systems for potential applications in green electrochemical devices.