Preparation of dual-phase composite BaCe0.8Y0.2O3/Ce0.8Y0.2O2 and its application for hydrogen permeation

Dual-phase ceramic membranes composed of BaCe0.8Y0.2O3 (BCY) and Ce0.8Y0.2O2 (CYO) were successfully synthesized by solid state reaction method for hydrogen permeation. The influences of the BCY/CYO volume ratios on phase composition, microstructure, chemical stability and electrical property were investigated. The hydrogen permeation of the dual-phase composite was characterized as a function of temperature and feed side hydrogen partial pressure. The results showed that there was no reaction between the two constituent oxides observed under the preparation conditions. The dual-phase composite with different BCY/CYO volume ratios after sintering at 1550 °C exhibited dense structure, as well as good stability in 4% H2/Ar, wet Ar and pure CO2 atmosphere. The conductivity of the dual-phase composite increased with the content of CYO increasing and 30BCY-70CYO exhibited the highest total conductivity of 2.6×10−2 S cm−1 at 800 °C in 4% H2/Ar. The hydrogen permeability of 30BCY-70CYO sample was improved as the temperature and the hydrogen partial pressure in feed gas increased. The hydrogen permeation flux of 1.7 μmol cm−2 s−1 was achieved at 850 °C.