A comprehensive study of the properties of coatings formed on a magnesium alloy by plasma electrolytic oxidation(PEO) using the electrolytes with nanosized particles of anatase(titanium dioxide) has been carried out. ...A comprehensive study of the properties of coatings formed on a magnesium alloy by plasma electrolytic oxidation(PEO) using the electrolytes with nanosized particles of anatase(titanium dioxide) has been carried out. Formed coatings reduce corrosion current density 2.5-fold and increase hardness by 25% compared to a coating without particles. Confocal micro-Raman spectroscopy revealed the presence of anatase and rutile phases in the composition of PEO coating due to the incorporation of TiO2nanoparticles during plasma electrolytic treatment. The presence of titanium dioxide had a positive effect on the photocatalytic properties of coatings: the constant rate of the methyl orange and methyl blue decomposition is increased in 1.6 and 1.8-fold, respectively, compared to the coating formed in electrolyte without TiO_(2) particles.展开更多
The Bi_(2)O_(3)/Bi_(2)SiO_(5) heterostructures were obtained with various samples of silica as a precursor:on the basis of biogenic silica isolated from rice husk and rice straw and the silica of mineral ori-gin.A mix...The Bi_(2)O_(3)/Bi_(2)SiO_(5) heterostructures were obtained with various samples of silica as a precursor:on the basis of biogenic silica isolated from rice husk and rice straw and the silica of mineral ori-gin.A mixture of Bi(NO_(3))_(3) and SiO_(2) with a mass content of 15%was used for synthesizing all the samples.Fourier transform infrared(FT-IR)spectroscopy,scanning electron microscope(SEM),X-ray phase,X-ray fluorescence,and ultraviolet-visible diffused reflectance spectroscopy(UV-vis DRS)were used to systematically characterize as-obtained materials.Photodegradation of methyl orange in neutral aqueous solutions(pH=6.8)under UV irradiation was studied to evaluate their photocatalytic activities.Morphology,bandgaps,the value of the zero charge point,and photo-catalytic activity of the samples depended on the characteristics of the original silica.The degree of methyl orange degradation reached the maximum values(81%−85%)for samples based on precipitated silica from rice husks,straw,and the minimum value(16%)for a composite with thermal silica from rice straw.Composites based on thermal silica from rice husks and reagents from mineral raw materials did not statistically differ from each other in the degree of methyl orange degradation(67%−74%).展开更多
TiO_(2)-B/anatase nanotubes doped by vanadium have been synthesized through a facile one-step hydrothermal reaction.The material shows a mesoporous structure with a specific surface area of 179.1 m^(2)g^(-1).XPS data ...TiO_(2)-B/anatase nanotubes doped by vanadium have been synthesized through a facile one-step hydrothermal reaction.The material shows a mesoporous structure with a specific surface area of 179.1 m^(2)g^(-1).XPS data presume the presence of V^(3+),V^(4+),V^(5+),and Ti^(3+) in doped TiO2-B/anatase.As found by XRD and EIS investigations,the vanadium expands bronze titania crystal structure and enhances the conductivity of material by three orders of magnitude.When tested for lithium storage,the V-modified titania nanotubes show a specific capacity of 133 mA h g^(-1) after 100 charge/discharge cycles at the current density of 3000 mA g^(-1) with a Coulombic efficiency of around 98.9%,resulting in its good cycleability.The material still possesses a reversible capacity of 114 mA h g^(-1) at a very high current load of 6000 mA g^(-1),demonstrating superior rate characteristics for secondary lithium batteries.Furthermore,V-doped Ti O2-B/anatase mesoporous nanotubes show promise performance as anode material for sodium-ion batteries,delivering about 119 mA h g^(-1) and 101 m A h g^(-1) at the current loads of 10 and 1500 m A g^(-1),respectively.展开更多
基金carried out within the framework of the grant of the Russian Science Foundation.project No. 22-23-00937。
文摘A comprehensive study of the properties of coatings formed on a magnesium alloy by plasma electrolytic oxidation(PEO) using the electrolytes with nanosized particles of anatase(titanium dioxide) has been carried out. Formed coatings reduce corrosion current density 2.5-fold and increase hardness by 25% compared to a coating without particles. Confocal micro-Raman spectroscopy revealed the presence of anatase and rutile phases in the composition of PEO coating due to the incorporation of TiO2nanoparticles during plasma electrolytic treatment. The presence of titanium dioxide had a positive effect on the photocatalytic properties of coatings: the constant rate of the methyl orange and methyl blue decomposition is increased in 1.6 and 1.8-fold, respectively, compared to the coating formed in electrolyte without TiO_(2) particles.
基金a part of the State Order of the Institute of Chemistry of the Far Eastern Branch of the Russian Academy of Sciences,project No.FWFN (0205)-2022-0003support of the Russian Science Foundation (grant No.19-73-10017).
文摘The Bi_(2)O_(3)/Bi_(2)SiO_(5) heterostructures were obtained with various samples of silica as a precursor:on the basis of biogenic silica isolated from rice husk and rice straw and the silica of mineral ori-gin.A mixture of Bi(NO_(3))_(3) and SiO_(2) with a mass content of 15%was used for synthesizing all the samples.Fourier transform infrared(FT-IR)spectroscopy,scanning electron microscope(SEM),X-ray phase,X-ray fluorescence,and ultraviolet-visible diffused reflectance spectroscopy(UV-vis DRS)were used to systematically characterize as-obtained materials.Photodegradation of methyl orange in neutral aqueous solutions(pH=6.8)under UV irradiation was studied to evaluate their photocatalytic activities.Morphology,bandgaps,the value of the zero charge point,and photo-catalytic activity of the samples depended on the characteristics of the original silica.The degree of methyl orange degradation reached the maximum values(81%−85%)for samples based on precipitated silica from rice husks,straw,and the minimum value(16%)for a composite with thermal silica from rice straw.Composites based on thermal silica from rice husks and reagents from mineral raw materials did not statistically differ from each other in the degree of methyl orange degradation(67%−74%).
文摘TiO_(2)-B/anatase nanotubes doped by vanadium have been synthesized through a facile one-step hydrothermal reaction.The material shows a mesoporous structure with a specific surface area of 179.1 m^(2)g^(-1).XPS data presume the presence of V^(3+),V^(4+),V^(5+),and Ti^(3+) in doped TiO2-B/anatase.As found by XRD and EIS investigations,the vanadium expands bronze titania crystal structure and enhances the conductivity of material by three orders of magnitude.When tested for lithium storage,the V-modified titania nanotubes show a specific capacity of 133 mA h g^(-1) after 100 charge/discharge cycles at the current density of 3000 mA g^(-1) with a Coulombic efficiency of around 98.9%,resulting in its good cycleability.The material still possesses a reversible capacity of 114 mA h g^(-1) at a very high current load of 6000 mA g^(-1),demonstrating superior rate characteristics for secondary lithium batteries.Furthermore,V-doped Ti O2-B/anatase mesoporous nanotubes show promise performance as anode material for sodium-ion batteries,delivering about 119 mA h g^(-1) and 101 m A h g^(-1) at the current loads of 10 and 1500 m A g^(-1),respectively.
