Affiliation:
1. Taras Shevchenko National University of Kyiv
2. bNational University of Life and Environmental Sciences of Ukraine
3. cG.M.Kurdyumov Institute for Metal Physics of the N.A.S. of Ukraine
Abstract
Addition of alkaline fluorides to molten phosphates with a composition MI2O-Р2О5-Mn2O3 and MI2O-Р2О5-MIIO (МI – Li, Na, K) gradually changes the solubility of polyvalent metals oxides and shifts the crystallization areas in the corresponding melts. The results obtained are based on solubility curves found for Mn2O3, СоО and NiO in the fluxes of MI2O-Р2О5 -MF and MI2O-Р2О5 -MF (where МI – Li, Na, K) and X-Ray diffraction, IR spectroscopy and thermal analysis. The presence of 10 and 20 % mass of fluorides provides molten polyphosphates depolymerization and yields pyro- Li2MnP2O7, K2CoP2O7, Na2CoP2O7and orthophosphates Na2Mn3(P2O7)2, NaMnPO4, NaNiPO4 single crystals growth.
Publisher
Taras Shevchenko National University of Kyiv
Reference11 articles.
1. Nagorny РG., Slobodyanik NS., Ushchapivska ТI. Lavrik RV. Double phosphates NaMn6(P3O10)(P2O7)2 and KMn6(P3O10)(P2O7)2 - advanced functional materials. Functional materials.2018; 25(4):689-694. https://doi.org/10.15407/fm25.04.689
2. Tanabe M, Honma T, Komatsu T. Unique crystallization behavior of sodium manganese pyrophosphate Na2MnP2O7 glass and its electrochemical properties. Journal of Asian Ceramic Societies 2017;5(2):209-215. https://doi.org/10.1016/j.jascer.2017.04.009
3. Shakoor RA., Kahraman R, Raja AA. Thermal Insitu Analyses of Multicomponent Pyrophosphate Cathodes Materials. Int. J. Electrochem. Sci, 2015;10:8941-8950.
4. Savchenko D, Kopilevich V, Voitenko L. Zinc cadmium ammine aqua monophosphate and its thermal transformations. Russian Journal of Applied Chemistry 2008;81(9):1492-1496. https://doi.org/10.1134/s1070427208090036
5. Kopilevich VA., Voitenko LV., Prokopchuk NM. The thermolysis of hydrated monophosphates of divalent transition metal. Vopr. Kh. i Kh.Tekn., 2018; 42(4):19 -26.