Browsing by Author "Tyuliev G.G."
Now showing 1 - 2 of 2
Results Per Page
Sort Options
Item Influence of heat treatment on the phase transition of ZrMo 2O8 and photocatalytic activity(2011-06-01) Mancheva M.N.; Iordanova R.S.; Dimitriev Y.B.; Tyuliev G.G.; Iliev T.C.ZrMo2O7(OH)2 •2H2O was obtained from ZrOCl2•2H2O and Na2MoO 4•2H2O by a coprecipitation method. The phase and structural changes occurred during the heat-treatment of ZrMo2O 7(OH) 2•2H2O were investigated by XRD, IR and XPS analysis. The sequence of phase transformation can be divided into three stages: (1) transformation of ZrMo2O7(OH) 2•2H2O to orthorhombic LT-ZrMo2O 8 up to 300°C; (2) obtaining of mixture of both polymorphs of ZrMo2O8: cubic and trigonal at 400°C; (3) conversion to single trigonal (α) ZrMo2O8 above 450°C. The microstructure of the obtained trigonal (α) ZrMo2O8 was observed by scanning electron microscopy (SEM). The particle sizes were below 0.5 μm. The specific surface area was measured by modified BET method. The photocatalytic activity of the obtained trigonal (α) ZrMo 2O8 powders was investigated by degradation of a model aqueous solution of Malachite Green (MG) upon UV-light irradiation. © Versita Sp. z o.o.Item Influence of heat treatment on the phase transition of ZrMo 2O8 and photocatalytic activity(2011-06-01) Mancheva M.N.; Iordanova R.S.; Dimitriev Y.B.; Tyuliev G.G.; Iliev T.C.ZrMo2O7(OH)2 •2H2O was obtained from ZrOCl2•2H2O and Na2MoO 4•2H2O by a coprecipitation method. The phase and structural changes occurred during the heat-treatment of ZrMo2O 7(OH) 2•2H2O were investigated by XRD, IR and XPS analysis. The sequence of phase transformation can be divided into three stages: (1) transformation of ZrMo2O7(OH) 2•2H2O to orthorhombic LT-ZrMo2O 8 up to 300°C; (2) obtaining of mixture of both polymorphs of ZrMo2O8: cubic and trigonal at 400°C; (3) conversion to single trigonal (α) ZrMo2O8 above 450°C. The microstructure of the obtained trigonal (α) ZrMo2O8 was observed by scanning electron microscopy (SEM). The particle sizes were below 0.5 μm. The specific surface area was measured by modified BET method. The photocatalytic activity of the obtained trigonal (α) ZrMo 2O8 powders was investigated by degradation of a model aqueous solution of Malachite Green (MG) upon UV-light irradiation. © Versita Sp. z o.o.