Proton diffusion in perovskites by Elastic and Quasi-Elastic Neutron Scattering measurement
|Aneta Slodczyk 1,2, Philippe Colomban 1, Daniel Lamago 3, Olivier Lacroix 2,4, Stephanie Willemin 2,4, Beatrice Sala 2,4|
1. Lab Dynamique Interaction et Reactivite, CNRS and Univ Paris VI (LADIR), 2 rue Henry Dunant, Thiais 94320, France
Thanks to their relative low functioning temperature the proton conducting perovskite ceramics are the most promising electrolytes for fuel cell and electrolyser applications1. Prior to the better industrial application it is necessary to understand the nature, diffusion and conduction mechanism of the protonic species. Neutron scattering experiments are very well suited to study the proton content, structure and dynamics of the proton conductors due to the very large cross-section of the hydrogen element. Elastic/quasi-elastic neutron studies were performed as the function of high temperature and momentum transfer for protonated Ln-modified BaZrO3 using the three axis spectrometers: 1T1 and 4F1 at the Leon Brillouin Laboratory (Saclay, France). Simultaneously, the neutron diffraction patterns were recorded permitting to follow the structural modifications. The results show the presence of the protonic species in the dense ceramic, their successive motion from 400 to 600°C and then the departure above 750°C under high vacuum conditions2. The QNS results are compared with the conductivity and thermal expansion measurements.
1. PCT patent WO 2008/152317 A2 (18-12-2008), Method for optimising the conductivity provided by the displacement of H+ protons and/or OH- ions in a conductive membrane.
2. A. Slodczyk, Ph. Colomban, D. Lamago, MH. Limage, F. Romain, S. Willemin, B. Sala Phase transitions in the H+ -conducting perovskite ceramics by the quasi-elastic neutron and high-pressure Raman scattering, Ionics 14 (2008) 215
Presentation: Oral at E-MRS Fall Meeting 2009, Symposium G, by Aneta Slodczyk
See On-line Journal of E-MRS Fall Meeting 2009
Submitted: 2009-05-11 11:29 Revised: 2009-06-07 00:48