Synergic Effect of Metal and Fluorine Doping on the Structural and Electrical Properties of LaMoO-Based Materials.

Cationic and anionic frameworks of LaMoO proton conductors have been modified by means of metal (Ti, Zr, and Nb) and fluorine (F) doping. This synergic effect leads to the stabilization of high-symmetry and single-phase polymorphs. The materials have been fully characterized by structural techniques, such as X-ray and neutron powder diffraction and transmission electron microscopy. The fluorine content was determined by ion chromatography. Impedance spectroscopy analysis under different atmospheres (dry and wet N and O and wet 5% H-Ar) showed an improvement in the electronic conductivity under reducing conditions, making these materials potential candidates for hydrogen separation membranes.