Unravelling the crystal structure of NdWO and NdWMoO mixed ionic electronic conductors.

Mixed ionic electronic conducting ceramics Nd WO (δ is the oxygen deficiency) provide excellent stability in harsh environments containing strongly reactive gases such as CO, CO, H, HO or HS. Due to this chemical stability, they are promising and cost-efficient candidate materials for gas separation, catalytic membrane reactors and protonic ceramic fuel cell technologies. As in La WO, the ionic/electronic transport mechanism in Nd WO is expected to be largely controlled by the crystal structure, the conclusive determination of which is still lacking.

Synthesis and characterization of nonsubstituted and substituted proton-conducting La(6-x)WO(12-y).

Mixed proton-electron conductors (MPEC) can be used as gas separation membranes to extract hydrogen from a gas stream, for example, in a power plant. From the different MPEC, the ceramic material lanthanum tungstate presents an important mixed protonic-electronic conductivity. Lanthanum tungstate La(6-x)WO(12-y) (with y = 1.

Enhanced H2 separation through mixed proton-electron conducting membranes based on La5.5 W0.8 M0.2 O11.25-δ.

La(5.5) WO11.25-δ is a proton-conducting oxide that shows high protonic conductivity, sufficient electronic conductivity, and stability in moist CO2 environments.