Multiple-doped barium cerate proton-conducting electrolytes for chemical-energy cogeneration in solid oxide fuel cells

Abstract

Proton-conducting perovskite oxides such as doped barium cerate and barium zirconate are promising electrolytes for solid oxide fuel cells (SOFCs). Multiple-doped barium cerate perovskite oxide proton conductors of BaCe0·7Zr0·1Y0.2-xNdxO3−δ (0 ≤ x ≤ 0.1) are prepared by solid state reaction and the properties of the fabricated material are characterized by various technologies. Nd doping improves the sinterability and Zr doping enhances the chemical stability in CO2 atmosphere. The electrical conductivity order of the as-prepared electrolytes at elevated temperature in hydrogen atmosphere is: BaCe0·7Y0·17Zr0.1Nd0.03O3−δ > BaCe0·7Y0·2Zr0·1O3−δ > BaCe0·7Y0·1Zr0.1Nd0.1O3−δ. Ethane is selectively dehydrogenated to ethylene with cogeneration of electrical power in the SOFC operated at 650–700 °C. The maximum power density of the SOFC is 123 mW cm−2 for ethane fuel and 138 mW cm−2 for hydrogen fuel at the 700 °C. These unique features make the multiple-doped barium cerate perovskite oxide a promising electrolyte for chemical-energy cogeneration in SOFCs.