Preparation, proton conduction, and application in ammonia synthesis at atmospheric pressure of La0.9Ba0.1Ga1–xMgxO3–a

La0.9Ba0.1Ga1–xMgxO3–a (0 B x B 0.25) was prepared by the microemulsion method. A single phase of LaGaO3 perovskite structure was formed when x was C0.15. Electrochemical hydrogen permeation (hydrogen pumping) proved that La0.9Ba0.1Ga1–xMgxO3–a had proton conduction, and the proton conduction was measured by AC impedance spectroscopy method from 400 to 800 C in hydrogen atmospheres. Among these samples, La0.9Ba0.1 Ga0.8Mg0.2O3–a has the highest proton conductivity with the values of 9.51 9 10-4 to 4.68 9 10-2 S cm-1 at 400– 800 C. Ammonia was synthesized from nitrogen and hydrogen at atmospheric pressure in an electrolytic cell using La0.9Ba0.1Ga0.8Mg0.2O3–a as electrolyte. The rate of NH3 formation was 1.89 9 10-9 mol s-1 cm-2 at 520 C upon imposing a current of 1 mA through the cell.