Elzbieta Filipek

Reactivity of T-Nb2O5 or H-Nb2O5 towards V2O5. Synthesis in the solid state and properties of V4Nb18O55

The IR spectrum of V4Nb18O55 has been compared with the IR spectra of selected niobates of known structures to show structural relations between these compounds. This comparison shows that V4Nb18O55 has crystal structure related to T-Nb2O5, W16Nb18O94 and Ba2NaNb5O15.On the other hand, reaction between V2O5 and H-Nb2O5 yields a solid solution of V2O5 in VNb9O25. It has been proposed two models of synthesized solid solution with formulas V1+xNb9-xO25 or V1+xNb9O25+5x/2.Independently of Nb2O5 polymorph, used for synthesis, the metastable compound VNbO5 cannot be synthesized in the solid state below 650°C

Phase relations up to the solidus line in the part of the Sb-Zn-O system

AbstractPhase relations up to the solidus line in part of the Sb-Zn-O system have been investigated over the entire concentration range of the α-Sb2O4-ZnO system in air (

Homogeneity area of MoO3 solid solution in SbVO5 in air

P_{O_2 }

Unknown thermal properties of ZnSb2O6 and Zn7Sb2O12 compounds

= 0.21 atm) using XRD and DTA/TG. The components of this system in air form ZnSb2O6 and Zn7Sb2O12. The results allow division of the system into three subsystems, i.e. α-Sb2O4-ZnSb2O6; ZnSb2O6Zn7Sb2O12 and Zn7Sb2O12-ZnO. The temperature ranges over which the ZnSb2O6 and Zn7Sb2O12 remain at equilibrium with other solid compounds depend on the gaseous atmosphere.

Comparison between the synthesis in molybdenum and antimony oxides system by high-temperature treatment and high-energy ball milling

In the work presented here, the way of obtaining the phase with general formula Co3+1.5xCr2–x(VO4)4 (0 ≤ × < 0.4) is demonstrated. A new phase is detected in CrVO4 - Co3V2O8 that is formed in one of the intersection of the ternary CoO - V2O5 - Cr2O3 system. Monophasic Co3Cr2(VO4)4 (Co3+1.5xCr2−x(VO4)4, where × = 0) was obtained from both a mixture comprising CrVO4 and Co3V2O8 as well as from the mixture of CoV2O6 with CoCr2O4. The Co3+1.5xCr2−x(VO4)4 is isotypic with the those demonstrating the lyonsite-type structure. The temperature of melting for the new compound was established using the DTA methods.