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
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%).
