Influence of temperature on the impedance of ionic polymer metal composites

• Nafion-based ionic polymer metal composites were fabricated.
• Impedance measurements were conducted for testing temperature from 25 to 40 °C.
• The resistance, capacitance, and Warburg impedance were experimentally identified.
• Temperature was found to influence both the dielectric and diffusion properties.

In this letter, we study the effect of temperature on the electric impedance of ionic polymer metal composites (IPMCs). Experiments are performed on in-house fabricated Nafion-based samples for temperatures varying from 25 to 40 °C. By using a recently proposed physics-based circuit model, we identify the equivalent resistance, capacitance and Warburg impedance of each sample, and characterize their dependence on temperature. We find that the resistance and the capacitance decrease as the temperature increases, while the Warburg impedance increases. Such variations are ultimately associated with the effect of temperature on the dielectric constant and the diffusivity of the IPMC.