Improvement in the sintering and electrical properties of strontium- and magnesium-doped lanthanum gallate by MoO3 dopant

The LSGM powders by doping 0–2.5 at.% of MoO3 were synthesized and investigated. The microstructure and electrical properties of the samples were characterized by X-ray diffraction (XRD), field-emission scanning electron microscopy (FE-SEM) and electrochemical impedance spectroscopy (EIS) respectively. The results showed that the phase purity, densification and conductivity of the LSGM samples could be improved by a proper addition of MoO3. The LSGM specimen by doping 2 at.% MoO3 exhibited the best phase purity, the best density, the largest grain size and the lowest activation energy. Moreover, it was found that the conductivity of the LSGM by doping 2 at.% MoO3 was 3.91 × 10−4 S cm−1 at 450 °C, which was 2.82 times as high as LSGM without MoO3 doping. Moreover, the thermal expansion coefficient of the LSGM-2Mo sample changed little by MoO3 doping. Therefore, the MoO3 doped LSGM may be a potential electrolyte material for anode-supported solid oxide fuel cells (SOFCs) without requiring buffer layer between anode and electrolyte. •MoO3 was added to LSGM sample and plays the role as sintering aid.•The phase purity and ionic conductivity of the sample was improved by adding MoO3.•The 2 at.% MoO3-doped LSGM specimen exhibited the best property.