(NH4)3PW12O40-H3PO4 composites as efficient proton conductors at intermediate temperatures

• 来源期刊: 材料科学技术（英文版）
• 年，卷（期）: 2020,（2）
• 页码范围: 128-134
• 页数: 7页
• 语种: 英文

摘要

(NH4)3PW12O40 and (NH4)3PW12O40-H3PO4 composites have been synthesized by precipitation method.Their phase compositions,thermal stability and morphologies have been investigated.The synthesized composites maintain the same structures as pure (NH4)3PW12O40 where phosphoric acid is preserved in residual space of the "spongy crystals" of (NH4)3PW12O40.FT-IR spectra confirm the strong interactions between phosphoric acid and Keggin ions.Pristine (NH4)3 PW12 O40 shows poor conductivity in air at high temperatures and strongly depends on water molecules for proton transport.The composites exhibit a much higher conductivity compared with pure (NH4)3PW12O40.The highest conductivity achieved is 0.14 S/cm at 170 ℃ where continuous channels based on phosphoric acid for proton transportation are probably established.Such high conductivity of (NH4)3PW12O40-H3PO4 composites implies promising applications in fuel cells and other electrochemical devices.