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)3PW12O40 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.
(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）3PW12O40 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.
基金
supported financially by the National Natural Science Foundation of China(No.21401142,51972233)
the Natural Science Foundation of Shanghai(No.19ZR1459200)
the National 1000-Plan Program
the Shanghai Science and Technology Commission(No.14DZ2261100)
the South Taihu Elite Project
the Fundamental Research Funds for the Central Universities.
