Proton diffusivity in the BaZr0.9Y0.1O3−δ proton conductor
Braun, Artur ; Duval, Sophie ; Ried, Peter ; Embs, Jan ; Juranyi, Fanni ; Strässle, Thierry ; Stimming, Ulrich ; Hempelmann, Rolf ; Holtappels, Peter ; Graule, Thomas
In: Journal of Applied Electrochemistry, 2009, vol. 39, no. 4, p. 471-475
Aggiungi alla tua lista- Summary
- The thermally activated proton diffusion in BaZr0.9Y0.1O3−δ was studied with electrochemical impedance spectroscopy (IS) and quasi-elastic neutron scattering (QENS) in the temperature range 300-900K. The diffusivities for the bulk material and the grain boundaries as obtained by IS obey an Arrhenius law with activation energies of 0.46eV and 1.21eV, respectively. The activation energies obtained by IS for the bulk are 0.26eV above 700K and 0.46eV, below 700K. The total diffusivity as obtained by IS is by one order of magnitude lower than the microscopic diffusivity as obtained by QENS. The activation energies obtained by QENS are 0.13eV above 700K and 0.04eV, below 700K. At about 700K, the diffusion constants for IS and QENS have a remarkable crossover, suggesting two processes with different activation energies