【摘 要】
：
Single crystals of LaP3O9·3H2O were prepared using a classical method of aqueous chemistry whereas those of the ultraphosphate LaP5O14 were obtained by flux me
【机 构】
：
Research Unit of Rare Earth Materials
论文部分内容阅读
Single crystals of LaP3O9·3H2O were prepared using a classical method of aqueous chemistry whereas those of the ultraphosphate LaP5O14 were obtained by flux method. Thermal treatment of LaP3O9·3H2O up to 700 ℃ allowed us to obtain the lanthanum polyphosphate La(PO3)3. The conductivity as well as the vibrational study of the lanthanum ultraphosphate and polyphosphate were analysed in order to explain the mechanism of conduction. Activation energies of 0.45 and 0.84 eV, deduced from the Amhenius relation, were respectively found for the polyphosphate and the ultraphosphate. Taking into account the structural features of these materials we linked the origin of their electrical properties to the incorporation of atmospheric humidity. Thus, it was a proton conduction phenomenon which took place as a result of the establishment of hydrogen bonds as well as the reorganisation of water molecules already incorporated into these structures. Referring to the Grotthuss mechanism, a proton transfer model inside the polyphosphate's structure was suggested.
其他文献
The influence of the manganese-alloying on the structure and magnetocaloric properties of the Gd5Si2.05Ge1.95 compound was studied by X-ray powder diffraction a
Ce-doped ZnO films were prepared by the sol-gel method with spin coating onto glass substrates.Zinc acetate dihydrate,ethanol,diethanolamine and cerium nitrate
The cross-sectional distortion usually appears during rotary-draw bending process of thin-walled rectangular tube with small bending radius. To study the cross-
Ce-Cu-O monolithic catalysts were prepared by using Ce0.9Cu0.101.9 solid solution or nitrate as precursors,and their catalytic performance for the combustion of
Using solid-state synthesis method,a series of samples of lanthanum doped Li1-xLaxFePO4(x=0.0025,0.005,0.0075,0.01)were prepared.Each cathode structural and ele
In order to obtain the thermodynamic description of the Mg-Ga binary system, the thermodynamic assessment of the system was carried out using the CALPHAD method
The microstructure and properties of the 93W-4Ni-2Co-1Fe (mass fraction, %) tungsten heavy alloys prepared by mechanical alloying and electric current activated
With the development of aero-engine,gas import temperatures of hot section structural materials are increasingly higher.Metal alloy materials due to the rapidly
We investigated the transport properties of isoelectronic substitution of Yb by Ca for Zintl phase YbCd2Sb2 below 300 K.The p-type Yb1-xCaxCd2Sb2(0.2≤x≤0.8)sa
The β-SiC/SiO2 core-shell nanowires with the "stem-and-node" structure were synthesized in the presence of cerium oxide by the carbothermal reduction of the st