The proton conductivity of heteropoly compounds

Five kinds of molybdovanadophosphoric acid: H7[P2Mo17VO62], H8[P2Mo16V2O62], H9[P2Mo15V3O62], H8[P2Mo14V4O61(H2O)] and H9[P2Mo13V5O61(H2O)] have been synthesized. The salts, K13[Ln(SiW11O39)2] (Ln=La, Ce, Pr, Nd or Gd) have also been prepared. The proton conductivities (C) of all the above compounds have been measured, and are dependent not only on the nature of compound itself, but also on external factors such as temperature and frequency. The general trend of proton conductivity, changing with the hydration number, frequency and temperature is summarized and important conclusions have been drawn based on experimental measurements. The resulting data have not been reported hitherto in the literature.