In-situ Neutron Diffraction study of BaCe0.4Zr0.4Y0.2O3−δ Proton Conducting Perovskite

ALONSO, J. A.; FERNÁNDEZ-DÍAZ, MARÍA T.; BASBUS J.F.; GONZALEZ M.; SERQUIS, ADRIANA C.; ARCE M.D.; CUELLO, GABRIEL J.; MOGNI L.V

Congreso; Annual Meeting 2020 of Nanoscience and Nanotechnology Institute (INN); 2020

Ba(Ce,Zr)O3-based materials have potential application as electrolytes for PC-SOFCs due to lower operating temperatures andhigher efficiencies respect to commercial electrolytes. Also, these materials have been proposed for PC-SOECs electrolyte, isotopicseparation membranes and water sensors. The. understanding of protonic defect mobilities and lattice distortions are crucial todevelop materials with high protonic conduction. BaCe0.4Zr0.4Y0.2O3−δ (BCZY) perovskite is a well-known proton conductor and theprotonic transport properties would depend on crystal structure and local distortions associated to temperatures and gas moist.Thus, BCZY perovskite was studied by Neutron Diffraction (ND) where the patterns were collected as a function of temperatureunder dry air and wet air (2 % heavy water vapor). The crystallographic and microstructural parameters were calculated. In addition,the phase transition from rhombohedral to cubic symmetry between 400 and 600 °C was determined. The D occupancy is full below400 °C and the second-order phase transition occurs at 520 °C when D occupancy is < 0,75. According to these results, theprotonic transport mechanism depends on D occupancy and it is not related to the phase transition.