(632b) Non-Equilibrium Molecular Dynamics Simulations of Yttria-Stabilized Zirconia Under An Alternating Electric Field

Yttria-stabilized zirconia(YSZ)is a high-temperature electrolyte commonly used in solid oxide fuel cells. Electrochemical impedance spectroscopy (EIS) analyses have been routinely applied experimentally to probe the electrical conductivity of YSZ. In this presentation, an alternate current non-equilibrium molecular dynamics (AC-NEMD) simulation technique is used to study the oxygen anion conduction behavior of 8% mol yttria-stabilized zirconia(YSZ). With ohmic heat generated by the external field, a constant temperature iss effectively maintained by both the Anderson and Nose-Hoover thermostats. Both thermostats yield similar results. The simulation results indicate a resistance-capacitance (RC) circuit behavior at low frequency and resistance-inductance (RL) circuit behavior at high frequency. The transition between RC and RL behavior is connected with the time of oxygen ions transport between oxygen vacancies in YSZ. Discussion of the discrepancies between simulation results and experimental data is attempted.