Synthesis of Sn0.9Al0.1P2O7−δ/KSn2(PO4)3 Composite Electrolyte Using NaCl/KCl Molten Salt

In this study, the fused salt NaCl/KCl was used to react with Sn0.9Al0.1P2O7−δ to synthesize Sn0.9Al0.1P2O7−δ/KSn2(PO4)3 composite electrolyte by in-situ reaction. The crystalline phase of the Sn0.9Al0.1P2O7−δ/KSn2(PO4)3 was analyzed by X-ray powder diffraction (XRD). The external and cross-sectional morphologies of the Sn0.9Al0.1P2O7−δ/KSn2(PO4)3 were observed by scanning electron microscope. The Sn0.9Al0.1P2O7−δ/KSn2(PO4)3 reaches maximum ionic conductivity of 7.7×10-2 S·cm-1 at 700 °C in a dry nitrogen atmosphere. The hydrogen concentration discharge cell verifies that the Sn0.9Al0.1P2O7−δ/KSn2(PO4)3 is a good protonic conductor in a hydrogen-containing atmosphere.