SILVER ION CONDUCTING SOLID BIOPOLYMER ELECTROLYTE AND USE OF THE SAME

Abstract

This study investigates the properties of xanthan gum (XG) based solid biopolymer electrolytes doped with silver nitrate (AgNO₃) for potential electrochemical applications. The impact of varying AgNO₃ concentrations (10, 20, and 30 wt.%) on the electrolyte's performance was analyzed using impedance spectroscopy. Measurements of the real impedance component as a function of frequency at room temperature revealed insights into the ionic transport behavior. Ionic conductivity was evaluated as a function of both salt concentration at 80 °C and frequency at room temperature. The maximum ionic conductivity observed for the 80XG: 20AgNO3 system. The results elucidate the relationship between AgNO₃ concentration, frequency, and ionic conductivity in XG-based biopolymer electrolytes, providing valuable information for optimizing their composition and performance.

Specification

Description:1. Impedance spectroscopy analysis of XG:AgNO₃ solid biopolymer electrolytes (100:0, 90:10, 80:20, and 70:30 weight ratios) at room temperature reveals the frequency dependence of the real impedance component. At low frequencies, Z' is typically high due to the limited response time of silver ions to the alternating electric field, resulting in reduced ion mobility and increased resistance. This behavior is characteristic of solid electrolytes with lower ionic conductivity. As frequency increases, Z' generally decreases. At high frequencies, Z' may plateau as the ions struggle to keep pace with the rapidly changing field, and the material's inherent resistance dominates the system response.
2. The ionic conductivity of the xanthan gum/silver nitrate system exhibits a peak at 20 wt.% AgNO₃. Below this concentration, conductivity increases with increasing AgNO₃ due to greater availability of Ag⁺ and NO₃⁻ ions, enhancing charge transport. The 20 wt.% concentration represents an optimal balance between ion availability and mobility within the xanthan gum matrix. Beyond this optimum, conductivity decreases due to excessive salt concentration, leading to ion clustering or incomplete dissociation. This aggregation of Ag⁺ ions reduces the number of free charge carriers, hindering conductivity.
3. Figure 3 illustrates the frequency-dependent conductivity variation across different AgNO3 concentrations. Conductivity increases with both frequency and AgNO3 doping (up to 20 wt.%) in the higher frequency range. At lower frequencies, conductivity is initially low but rises with increasing frequency and doping, likely due to charge transfer complex formation and reduced crystallinity in the biopolymer electrolytes. A sharp change in conductivity is observed at higher megahertz frequencies, attributed to the formation of ionic aggregates, which hinder ion transport.
, Claims:1. XG doped with AgNO3 solid biopolymer electrolytes (SBPEs) has been synthesized using a solution casting technique.
2. SBPE consists of biopolymer XG and silver salt AgNO3.
3. After the incorporation of 20 wt.% of AgNO3 salt, the ionic conductivity has been improved to 8.90 × 10-5 S/cm at 80 °C.
4. The minimum value of bulk resistance is observed for 80XG: 20AgNO3 system.

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