A stable, easily sintered proton-conducting oxide electrolyte for moderate-temperature fuel cells and electrolyzers

For proton-conducting oxides to be used in fuel cell and related technologies, sintering to form dense ceramics at low temperatures and avoiding carbonation of BaCeO3-based oxides is required. A new strategy that allows densification at much reduced temperatures (see figure) and provides high total conductivity, with the additional benefit of stabilization against degradation, is reported.