The CeTi 2O 6, which is formed above 1300 ℃ by ceramic method, was obtained at 700 ℃ using sol gel synthesis method. XRD analysis shows that there is 8% deficient of Ce in the structure. The chemical formula is C...The CeTi 2O 6, which is formed above 1300 ℃ by ceramic method, was obtained at 700 ℃ using sol gel synthesis method. XRD analysis shows that there is 8% deficient of Ce in the structure. The chemical formula is Ce 0.92 Ti 2O 5.84 , which has a monoclinic structure with space group of C 2/ m . Its cell parameters are a =0.9811(8) nm, b =0.3726(3) nm, c =0.6831(6) nm, and β =118.84°. After being treated at 1300 ℃ for 3 h, the system keeps stable but the deficient disappears, while the chemical formula change to the normal CeTi 2O 6, and the cell parameters are a =0.9813(3) nm, b =0.3752(4) nm, c =0.6883(5) nm, β =119.05°. The key to synthesis the precursors of CeTi 2O 6 is that Ti 4+ and Ce 3+ ions must reach the atomistic distributing state and prevent the oxidation of Ce 3+ during sol gel process.展开更多
A photocatalyst of nanometer TiO2/conjugated polymer complex was successfully synthesized and characterized by spectroscopic methods and photocatalytic experiments. The complex photocatalyst could be activated by abso...A photocatalyst of nanometer TiO2/conjugated polymer complex was successfully synthesized and characterized by spectroscopic methods and photocatalytic experiments. The complex photocatalyst could be activated by absorbing both ultraviolet and visible light （λ = 190-800 nm）. Methylene blue （MB） could be degraded more efficiently on the complex photocatalyst than on the TiO2 under natural light. The conjugated polymer played a promoting role in the photocatalytic degradation of MB. The calcination temperature had an important effect in degradation of dye and could be summarized as 260℃ 〉 300 ℃ 〉 340 ℃ 〉 220 ℃ 〉 180 ℃.展开更多
Based on the infrared characterization of methyl orange adsorption on TiO 2 surface and the titration of TiO 2, the triple layer model of methyl orange adsorption on TiO 2 was established according to electric double ...Based on the infrared characterization of methyl orange adsorption on TiO 2 surface and the titration of TiO 2, the triple layer model of methyl orange adsorption on TiO 2 was established according to electric double theory. The software FITEQL3.1 was applied to calculate the distribution of organic adsorption on TiO 2 surface by introducing dummy components to help to overcome mathematical difficulties. It is shown that the chem. adsorption species of methyl orange have a great adsorption amount. The adsorption constants of three kinds of surface complexation expressed as SOH +org -,SOH 2org 2 and SOHorg - are 5.98, 17.57 and -4.2, respectively.展开更多
A[H3AgI(H2O)PW11O39]3?‐TiO2/ITO electrode was fabricated by immobilizing a molecular polyoxometalate‐based water oxidation catalyst,[H3AgI(H2O)PW11O39]3?(AgPW11),on a TiO2electrode.The resulting electrode was charac...A[H3AgI(H2O)PW11O39]3?‐TiO2/ITO electrode was fabricated by immobilizing a molecular polyoxometalate‐based water oxidation catalyst,[H3AgI(H2O)PW11O39]3?(AgPW11),on a TiO2electrode.The resulting electrode was characterized by X‐ray powder diffraction,scanning electron microscopy,and energy dispersive X‐ray spectroscopy.Linear sweep voltammetry,chronoamperometry,and electrochemical impedance measurements were performed in aqueous Na2SO4solution(0.1molL?1).We found that a higher applied voltage led to better catalytic performance by AgPW11.The AgPW11‐TiO2/ITO electrode gave currents respectively10and2.5times as high as those of the TiO2/ITO and AgNO3‐TiO2/ITO electrodes at an applied voltage of1.5V vs Ag/AgCl.This result was attributed to the lower charge transfer resistance at the electrode‐electrolyte interface for the AgPW11‐TiO2/ITO electrode.Under illumination,the photocurrent was not obviously enhanced although the total anode current increased.The AgPW11‐TiO2/ITO electrode was relatively stable.Cyclic voltammetry of AgPW11was performed in phosphate buffer solution(0.1mol L?1).We found that oxidation of AgPW11was a quasi‐reversible process related to one‐electron and one‐proton transfer.We deduced that disproportionation of the oxidized[H2AgII(H2O)PW11O39]3?might have occurred and the resulting[H3AgIIIOPW11O39]3?oxidized water to O2.展开更多
The interaction between radionuclides and solid/water interfaces is important to understand the physicochemical processes of radionuclides in the natural environment.Herein,the interaction of 60Co(Ⅱ) with TiO 2 in aq...The interaction between radionuclides and solid/water interfaces is important to understand the physicochemical processes of radionuclides in the natural environment.Herein,the interaction of 60Co(Ⅱ) with TiO 2 in aqueous solution as a function of pH and ionic strength was studied by using batch technique combined with surface complexation model and density functional theory(DFT) calculations.The batch experimental results showed that the adsorption of 60Co(Ⅱ) was dependent on pH and independent of ionic strength,indicating the formation of inner-sphere surface complexes on TiO 2 surfaces.The results of surface complexation models and DFT calculations indicated that the surface species of 60Co(Ⅱ) adsorbed on TiO 2 followed the trend:B structure(i.e.,60Co(Ⅱ) was linked to one bridge oxygen site) was the dominant surface species at low pH,and TT structure(i.e.,60Co(Ⅱ) was linked to two terminal oxygen sites) became the important surface complex at neutral and alkaline pH values.These results demonstrated that a multi-technique approach could lead to definitive information on the structures of adsorbed 60Co(Ⅱ) at the molecular level at the TiO 2 /water interfaces,as well as realistic models to rationalize and accurately evaluate the macroscopic manifestations of radionuclide adsorption phenomena.展开更多
Two kinds of Ru(Ⅱ)-bipyridine complexes, cis-di(thiocyanate)bis(2,2′-bipyridyl-4,4′-dicarboxylate) ruthenium(Ⅱ) and cis-di(thiocyanate)bis(2,2′-bipyridyl-3,3′-dicarboxylate) ruthenium(Ⅱ), were utilized as the s...Two kinds of Ru(Ⅱ)-bipyridine complexes, cis-di(thiocyanate)bis(2,2′-bipyridyl-4,4′-dicarboxylate) ruthenium(Ⅱ) and cis-di(thiocyanate)bis(2,2′-bipyridyl-3,3′-dicarboxylate) ruthenium(Ⅱ), were utilized as the sensitizers to the nanocrystalline TiO-2 film electrodes. Study shows that the two dyes have quite different sensitization properties due to the strong steric effect of carboxyl groups. In addition, the pretreatment to nanocrystalline TiO-2 film electrodes with TiCl-4 was investigated, which is an effective way to improve the photoelectric conversion performances of sensitized TiO-2 electrodes.展开更多
文摘The CeTi 2O 6, which is formed above 1300 ℃ by ceramic method, was obtained at 700 ℃ using sol gel synthesis method. XRD analysis shows that there is 8% deficient of Ce in the structure. The chemical formula is Ce 0.92 Ti 2O 5.84 , which has a monoclinic structure with space group of C 2/ m . Its cell parameters are a =0.9811(8) nm, b =0.3726(3) nm, c =0.6831(6) nm, and β =118.84°. After being treated at 1300 ℃ for 3 h, the system keeps stable but the deficient disappears, while the chemical formula change to the normal CeTi 2O 6, and the cell parameters are a =0.9813(3) nm, b =0.3752(4) nm, c =0.6883(5) nm, β =119.05°. The key to synthesis the precursors of CeTi 2O 6 is that Ti 4+ and Ce 3+ ions must reach the atomistic distributing state and prevent the oxidation of Ce 3+ during sol gel process.
文摘A photocatalyst of nanometer TiO2/conjugated polymer complex was successfully synthesized and characterized by spectroscopic methods and photocatalytic experiments. The complex photocatalyst could be activated by absorbing both ultraviolet and visible light （λ = 190-800 nm）. Methylene blue （MB） could be degraded more efficiently on the complex photocatalyst than on the TiO2 under natural light. The conjugated polymer played a promoting role in the photocatalytic degradation of MB. The calcination temperature had an important effect in degradation of dye and could be summarized as 260℃ 〉 300 ℃ 〉 340 ℃ 〉 220 ℃ 〉 180 ℃.
基金Project( 0 10 873and 0 10 15 1)supportedbytheNaturalScienceFoundationofGuandongProvince China +1 种基金Project(A3 0 40 3 0 1)supportedbytheScience&TechnologyDevelopmentFoundationofGuangdongProvince China
文摘Based on the infrared characterization of methyl orange adsorption on TiO 2 surface and the titration of TiO 2, the triple layer model of methyl orange adsorption on TiO 2 was established according to electric double theory. The software FITEQL3.1 was applied to calculate the distribution of organic adsorption on TiO 2 surface by introducing dummy components to help to overcome mathematical difficulties. It is shown that the chem. adsorption species of methyl orange have a great adsorption amount. The adsorption constants of three kinds of surface complexation expressed as SOH +org -,SOH 2org 2 and SOHorg - are 5.98, 17.57 and -4.2, respectively.
基金supported by the National Natural Science Foundation of China (21573099, 21601077, 21573100)~~
文摘A[H3AgI(H2O)PW11O39]3?‐TiO2/ITO electrode was fabricated by immobilizing a molecular polyoxometalate‐based water oxidation catalyst,[H3AgI(H2O)PW11O39]3?(AgPW11),on a TiO2electrode.The resulting electrode was characterized by X‐ray powder diffraction,scanning electron microscopy,and energy dispersive X‐ray spectroscopy.Linear sweep voltammetry,chronoamperometry,and electrochemical impedance measurements were performed in aqueous Na2SO4solution(0.1molL?1).We found that a higher applied voltage led to better catalytic performance by AgPW11.The AgPW11‐TiO2/ITO electrode gave currents respectively10and2.5times as high as those of the TiO2/ITO and AgNO3‐TiO2/ITO electrodes at an applied voltage of1.5V vs Ag/AgCl.This result was attributed to the lower charge transfer resistance at the electrode‐electrolyte interface for the AgPW11‐TiO2/ITO electrode.Under illumination,the photocurrent was not obviously enhanced although the total anode current increased.The AgPW11‐TiO2/ITO electrode was relatively stable.Cyclic voltammetry of AgPW11was performed in phosphate buffer solution(0.1mol L?1).We found that oxidation of AgPW11was a quasi‐reversible process related to one‐electron and one‐proton transfer.We deduced that disproportionation of the oxidized[H2AgII(H2O)PW11O39]3?might have occurred and the resulting[H3AgIIIOPW11O39]3?oxidized water to O2.
基金Progress of Projects Supported by NSFCsupported by the National Basic Research Program of China (2011CB933700)the National Natural Science Foundation of China (20907055,20971126,21071147,91126020,21077107)
文摘The interaction between radionuclides and solid/water interfaces is important to understand the physicochemical processes of radionuclides in the natural environment.Herein,the interaction of 60Co(Ⅱ) with TiO 2 in aqueous solution as a function of pH and ionic strength was studied by using batch technique combined with surface complexation model and density functional theory(DFT) calculations.The batch experimental results showed that the adsorption of 60Co(Ⅱ) was dependent on pH and independent of ionic strength,indicating the formation of inner-sphere surface complexes on TiO 2 surfaces.The results of surface complexation models and DFT calculations indicated that the surface species of 60Co(Ⅱ) adsorbed on TiO 2 followed the trend:B structure(i.e.,60Co(Ⅱ) was linked to one bridge oxygen site) was the dominant surface species at low pH,and TT structure(i.e.,60Co(Ⅱ) was linked to two terminal oxygen sites) became the important surface complex at neutral and alkaline pH values.These results demonstrated that a multi-technique approach could lead to definitive information on the structures of adsorbed 60Co(Ⅱ) at the molecular level at the TiO 2 /water interfaces,as well as realistic models to rationalize and accurately evaluate the macroscopic manifestations of radionuclide adsorption phenomena.
文摘Two kinds of Ru(Ⅱ)-bipyridine complexes, cis-di(thiocyanate)bis(2,2′-bipyridyl-4,4′-dicarboxylate) ruthenium(Ⅱ) and cis-di(thiocyanate)bis(2,2′-bipyridyl-3,3′-dicarboxylate) ruthenium(Ⅱ), were utilized as the sensitizers to the nanocrystalline TiO-2 film electrodes. Study shows that the two dyes have quite different sensitization properties due to the strong steric effect of carboxyl groups. In addition, the pretreatment to nanocrystalline TiO-2 film electrodes with TiCl-4 was investigated, which is an effective way to improve the photoelectric conversion performances of sensitized TiO-2 electrodes.
