Udakara, S.2024-10-242024-10-242004https://ir.lib.pdn.ac.lk/handle/20.500.14444/2470Transport properties of PAN: Cu(ClO₄)₂ polymer electrolyte and (PEO)₉CuCNS polymer electrolyte have been studied. Three PAN based electrolytes were made with different composition of polyacrylonitrile (PAN), ethylene carbonate (EC), propylene carbonate (PC) and copper perchlorate Cu(ClO₄)₂. The highest conductivity was obtained for the 20 wt% PAN: 41 wt% EC : 34 wt% PC: 5 wt% Cu(ClO₄)₂ system over the entire temperature range. DC impedance measurements show that this PAN based polymer electrolytes are predominantly ionic conductors and the AC impedance shows that the electrolytes reach conductivities of the order of 10⁻² Scm⁻¹ around 80 °C. Even at room temperature, the conductivity remains quite high, of the order of 10⁻³ Scm⁻¹. The temperature variations of all PAN based systems follow VTF behaviour and DC polarization measurements show that the dominant charge carriers appear to be ClO₄ DC measurements show that the composite polymer electrolyte (PEO)₉CuCNS+10wt%Al₂O₃ and polymer free electrolyte are mixed ion conductors, predominantly with anionic conductivity. Ionic conductivity of the composite electrolyte, (PEO)₉CuCNS+10wt%Al₂O₃ has enhanced substantially due to the presence of Al₂O₃ filler at temperatures above as well as below the PEO crystallite melting temperature (~ 60°C). This enhancement can be attributed to the creation of additional sites and favourable conducting pathways due to H- bonding between ClO₄⁻ and OH groups at Al₂O₃ grain surface. Another important conclusion that can be arrived from these observations is that the anionic transference number is significantly increased duc to the addition of Al₂O₃.en-USPhysics of materialsPolymerCopper saltsThesis