Synthesis, characteristics and electrical properties of heteropoly compound Na2K3CuV(OH2)W11O39·16H2O permeated by Gd

The permeation of the rare earth element gadolinium (Gd) to the heteropoly compound Na2K3CuV(OH2)W11O39·16H2O using the rare earth gas phase-heated diffused permeation method is reported for the first time. Inductively coupled plasma (ICP) and X-ray photoelectron spectroscopy (XPS) were used to determine the percentage composition of the rare earth element Gd in a permeated sample. Structures of compounds before and after permeation were investigated by infrared spectroscopy (IR) and X-ray diffraction (XRD). The results show that compound anions before permeation have the Keggin structure, while the Keggin cage structure is destroyed and a new compound is produced due to the permeation of Gd. Conductivity of compounds before and after permeation was investigated by ac impedance spectra. It reveals that conductivity of the permeated sample is greatly enhanced compared with the original sample. The thermal analysis result indicates that the thermostability of the permeated sample is improved.