LAUSR

Abstract In this study, Sn 0.95 Al 0.05 P 2 O 7 and a novel dense Sn 0.95 Al 0.05 P 2 O 7 /KSn 2 (PO 4 ) 3 composite electrolytes were synthesized. The structural characterization of X–ray diffraction (XRD) and microstructual properties of scanning electron microscopy (SEM) were carried out. The XRD results indicated that an in-situ reaction between Sn 0.95 Al 0.05 P 2 O 7 and inorganic melt salt take place to form the Sn 0.95 Al 0.05 P 2 O 7 /KSn 2 (PO 4 ) 3 composite. The intermediate temperature electrical properties were determined by using impedance spectroscopy, oxygen concentration cell and hydrogen concentration discharge cell. Finally, the H 2 /O 2 fuel cell using the Sn 0.95 Al 0.05 P 2 O 7 /KSn 2 (PO 4 ) 3 as electrolyte membrane was constructed and the obtained maximum power output densities were 67.7 mW cm −2 and 142.1 mW cm −2 at 650 °C and 700 °C, respectively.