N-F-codoped TiO2 (NFTO) photocatalysts were synthesized by a simple sol-gel process with tetrabutyl titanate (Ti(OBu)4 ) as the precursor of TiO 2 and ammonium fluoride (NH4 F) as the source of N and F.The syn...N-F-codoped TiO2 (NFTO) photocatalysts were synthesized by a simple sol-gel process with tetrabutyl titanate (Ti(OBu)4 ) as the precursor of TiO 2 and ammonium fluoride (NH4 F) as the source of N and F.The synthesized photocatalysts were investigated by X- ray diffraction (XRD),X-ray photoelectron spectroscopy (XPS),ultraviolet-visible diffuse reflectance spectroscopy (UV-Vis DRS) and photodegradation reaction tests of 4-chlorophenol under visible light irradiation to understand the relationship between the structure of NFTO catalyst and corresponding photocatalytic activity.The crystal phase and particle size of catalysts were found to be largely affected by the calcination temperature.In addition,N-F-codoping could inhibit phase transition of TiO2 from anatase to rutile.The presence of N and F atoms in the lattice of TiO2 is responsible for the visible light catalytic activity.In UV-Vis DRS tests,the spectrum of NFTO exhibited red shift compared with Degussa P25 and the band gap was reduced to around 2.92 eV.Under optimal calcination temperature and dopant concentration conditions,the NFTO photocatalyst exhibited the highest activity in the photodegradation reaction tests of 4-chlorophenol under visible light irradiation with a degradation rate of 75.84%.Besides,the 5-recycle test showed that NFTO photocatalyst could be reused and its activity kept stable under visible light irradiation.展开更多
First-principles plane-wave pseudopotential calculations are performed to study the geometrical structures, for- mation energies, and electronic and optical properties of Y-doped, N-doped, and (Y, N)-codoped Ti02. T...First-principles plane-wave pseudopotential calculations are performed to study the geometrical structures, for- mation energies, and electronic and optical properties of Y-doped, N-doped, and (Y, N)-codoped Ti02. The calculated results show that Y and N codoping leads to lattice distortion, easier separation of photogenerated electron-hole pairs and band gap narrowing. The optical absorption spectra indicate that an obvious red-shift occurs upon Y and N codoping, which enhances visible-light photocatalytic activity.展开更多
Nanometer SnO2 particles were synthesized by sol-gel dialytic processes and used as a support to prepare CuO supported catalysts via a deposition-precipitation method.The samples were characterized by means of TG-DTA,...Nanometer SnO2 particles were synthesized by sol-gel dialytic processes and used as a support to prepare CuO supported catalysts via a deposition-precipitation method.The samples were characterized by means of TG-DTA,XRD,H2-TPR and XPS.The catalytic activity of the CuO/TiO2-SnO2 catalysts was markedly depended on the loading of CuO,and the optimum CuO loading was 8 wt.%(Tloo=80℃).The CuO/TiO2-SnO2 catalysts exhibited much higher catalytic activity than the CuO/TiO2 and CuO/SnO2 catalysts.H2-TPR result indicated that a large amount of CuO formed the active site for CO oxidation in 8 wt.%CuO/TiO2-SnO2 catalyst.展开更多
Zr-doped-TiO2 loaded glass fiber(ZT/GF) composite photocatalysts with different Zr/Ti ratios were prepared with a sol–gel process. Zr4+can replace Ti4+in the TiO2 lattice, which is conducive to forming the anatas...Zr-doped-TiO2 loaded glass fiber(ZT/GF) composite photocatalysts with different Zr/Ti ratios were prepared with a sol–gel process. Zr4+can replace Ti4+in the TiO2 lattice, which is conducive to forming the anatase phase and reducing the calcination temperature. The glass fiber carrier was responsible for better dispersion and loading of Zr-doped-TiO2 particles, improving the applicability of the Zr-doped-TiO2. The ZT/GF photocatalysts were characterized by X-ray diffraction(XRD), scanning electron microscope(SEM), Fourier transform infrared spectroscopy(FT-IR), ultraviolet–visible spectroscopy(UV–vis) and Barrett–Joyner–Halenda(BJH). The performance of photocatalysts with different loading was evaluated in formaldehyde degradation under visible light at room temperature. ZT/GF0.2exhibited the highest activity, with a formaldehyde removal rate as high as 95.14% being observed, which is better than that of the photocatalyst particles alone. The stability of the catalyst was also tested, and ZT/GF exhibited excellent catalytic performance with 94.38%removal efficiency, even after seven uses.展开更多
A high active novel TiO2/AC composite photocatalyst was prepared and used for phenol degradation. It was much more active than P-25 and exhibiting good decantability, less deactivation after several runs and less sens...A high active novel TiO2/AC composite photocatalyst was prepared and used for phenol degradation. It was much more active than P-25 and exhibiting good decantability, less deactivation after several runs and less sensitive to pH change. Diffuse reflectance spectra (DRS) revealed that the electronic change in TiO2 did not occur by the addition of AC. Results of SEM and XRD suggested that better TiO2 distribution can be achieved when optimal AC content was adopted. The performance of the prepared TiO2/5AC catalyst revealed great practical potential in wastewater treatment field.展开更多
Using low-cost precipitated silica(SiO2) as the carrier,a ternary SiO2-TiO2/g-C3N4 composite photocatalyst was prepared via the sol-gel method associated with a wet-grinding process.The asprepared composite exhibits p...Using low-cost precipitated silica(SiO2) as the carrier,a ternary SiO2-TiO2/g-C3N4 composite photocatalyst was prepared via the sol-gel method associated with a wet-grinding process.The asprepared composite exhibits photocatalytic hydrogen production and pollutant degradation performance under solar-like irradiation.The effect of SiO2 carrier on the properties of the heterostructure between TiO2 and g-C3N4(CN) was systematically studied.It is found that SiO2 has important effects on promoting the interaction between TiO2 and CN.The particle size of TiO2 and CN was obviously reduced during the calcination process due to the effects of SiO2.Especially,the TiO2 particles exhibit monodispersed state with particle size below 10 nm(quantum dots),resulting in the improvement of the contact area and the interaction betweenTiO2 and CN,and leading to the formation of efficient TiO2/CN Zscheme heterostructure in SiO2-TiO2/CN.Besides,the introduction of SiO2 can increase the specific surface area and light absorption of SiO2-TiO2/CN,further promoting the photocatalytic reaction.As expected,the optimum SiO2-TiO2/CN composite exhibits 12.3,3.1 and 2.9 times higher photocatalytic hydrogen production rate than that of SiO2-TiO2,CN and TiO2/CN under solar-like irradiation,while the photocatalytic active component in SiO2-TiO2/CN is only about 60 wt%.Moreover,the rhodamine B degradation rate of SiO2-TiO2/CN is also higher than that of SiO2-TiO2,CN and TiO2/CN.展开更多
The photo absorbing, photo transmitting and photoluminescence performances of WiO2 photocatalysts compounded with V2O5 or WO3 were investigated by UV-Vis spectra, transmitting spectra, and PL spectra, respectively. Th...The photo absorbing, photo transmitting and photoluminescence performances of WiO2 photocatalysts compounded with V2O5 or WO3 were investigated by UV-Vis spectra, transmitting spectra, and PL spectra, respectively. The energy band structures of TiO2 photocatalysts were analyzed. The photocatalytic activities of the TiO2 photocatalysts were investigated by splitting of water for 02 evolution. The results indicate that the band gaps of WO3 and V205 are about 2.8 and 2.14 eV, respectively, and the band gap of rutile TiO2 is about 3.08 eV. Speeds of water splitting for 2%WO3-TiO2 and 8%V2O5-TiO2 photocatalysts are 420 and 110 μmol/(L.h), respectively, under UV light irradiation. V2O5 and WO3 compounded with suitable concentration can improve the photocatalytic activity of TiO2 with Fe3+ as electron acceptor.展开更多
基金supported by the Scienceand Technology Project of Education Commission of Chongqing of China(No.KJ110709)the Key Science Project of Ministry of Education of China(No.2008119)+1 种基金the Colleges and Universities Innovation Team Project of Chongqing of China(No.KJTD201020)the Scienceand Technology Project of Engineering Research Centre for Waste Oil,Ministry of Education of China(No.FYKJ2009012)
摘要N-F-codoped TiO2 (NFTO) photocatalysts were synthesized by a simple sol-gel process with tetrabutyl titanate (Ti(OBu)4 ) as the precursor of TiO 2 and ammonium fluoride (NH4 F) as the source of N and F.The synthesized photocatalysts were investigated by X- ray diffraction (XRD),X-ray photoelectron spectroscopy (XPS),ultraviolet-visible diffuse reflectance spectroscopy (UV-Vis DRS) and photodegradation reaction tests of 4-chlorophenol under visible light irradiation to understand the relationship between the structure of NFTO catalyst and corresponding photocatalytic activity.The crystal phase and particle size of catalysts were found to be largely affected by the calcination temperature.In addition,N-F-codoping could inhibit phase transition of TiO2 from anatase to rutile.The presence of N and F atoms in the lattice of TiO2 is responsible for the visible light catalytic activity.In UV-Vis DRS tests,the spectrum of NFTO exhibited red shift compared with Degussa P25 and the band gap was reduced to around 2.92 eV.Under optimal calcination temperature and dopant concentration conditions,the NFTO photocatalyst exhibited the highest activity in the photodegradation reaction tests of 4-chlorophenol under visible light irradiation with a degradation rate of 75.84%.Besides,the 5-recycle test showed that NFTO photocatalyst could be reused and its activity kept stable under visible light irradiation.
基金Project supported by the National Natural Science Foundation of China (Grant Nos. 10647008, 50971099, and 21176199)the Research Fund for the Doctoral Program of Higher Education, China (Grant Nos. 20096101110017 and 20096101110013)+1 种基金the Key Project of the Natural Science Foundation of Shaanxi Province, China (Grant Nos. 2010JZ002 and 2011JM1001)the Graduate Innovation Fund of Northwest University, China (Grant No. 10YZZ38)
摘要First-principles plane-wave pseudopotential calculations are performed to study the geometrical structures, for- mation energies, and electronic and optical properties of Y-doped, N-doped, and (Y, N)-codoped Ti02. The calculated results show that Y and N codoping leads to lattice distortion, easier separation of photogenerated electron-hole pairs and band gap narrowing. The optical absorption spectra indicate that an obvious red-shift occurs upon Y and N codoping, which enhances visible-light photocatalytic activity.
基金supported by the National Natural Science Foundation of China(20771061 and 20871071)the 973 Program(2005CB623607)Science and Technology Commission Foundation of Tianjin(08JCYBJC00100 and 09JCYBJC03600)
摘要Nanometer SnO2 particles were synthesized by sol-gel dialytic processes and used as a support to prepare CuO supported catalysts via a deposition-precipitation method.The samples were characterized by means of TG-DTA,XRD,H2-TPR and XPS.The catalytic activity of the CuO/TiO2-SnO2 catalysts was markedly depended on the loading of CuO,and the optimum CuO loading was 8 wt.%(Tloo=80℃).The CuO/TiO2-SnO2 catalysts exhibited much higher catalytic activity than the CuO/TiO2 and CuO/SnO2 catalysts.H2-TPR result indicated that a large amount of CuO formed the active site for CO oxidation in 8 wt.%CuO/TiO2-SnO2 catalyst.
基金financially supported by the Project of Science and Technology Department of Jiangsu Province (BE2016769)the Natural Science Foundation of China (No. 51608261)+2 种基金Six talent peaks project in Jiangsu Province (2016)Open fund by Jiangsu Engineering Technology Research Center of Environmental Cleaning Materials (KFK1503)A Project Funded by the Priority Academic Program Development of Jiangsu Higher Education Institutions (PAPD)
摘要Zr-doped-TiO2 loaded glass fiber(ZT/GF) composite photocatalysts with different Zr/Ti ratios were prepared with a sol–gel process. Zr4+can replace Ti4+in the TiO2 lattice, which is conducive to forming the anatase phase and reducing the calcination temperature. The glass fiber carrier was responsible for better dispersion and loading of Zr-doped-TiO2 particles, improving the applicability of the Zr-doped-TiO2. The ZT/GF photocatalysts were characterized by X-ray diffraction(XRD), scanning electron microscope(SEM), Fourier transform infrared spectroscopy(FT-IR), ultraviolet–visible spectroscopy(UV–vis) and Barrett–Joyner–Halenda(BJH). The performance of photocatalysts with different loading was evaluated in formaldehyde degradation under visible light at room temperature. ZT/GF0.2exhibited the highest activity, with a formaldehyde removal rate as high as 95.14% being observed, which is better than that of the photocatalyst particles alone. The stability of the catalyst was also tested, and ZT/GF exhibited excellent catalytic performance with 94.38%removal efficiency, even after seven uses.
基金This project was financially supported by Specialized Research Fund for the Doctoral Program of Higher Education (No. 20050225006)the National Natural Science Foundation of China (No. 30400339).
摘要A high active novel TiO2/AC composite photocatalyst was prepared and used for phenol degradation. It was much more active than P-25 and exhibiting good decantability, less deactivation after several runs and less sensitive to pH change. Diffuse reflectance spectra (DRS) revealed that the electronic change in TiO2 did not occur by the addition of AC. Results of SEM and XRD suggested that better TiO2 distribution can be achieved when optimal AC content was adopted. The performance of the prepared TiO2/5AC catalyst revealed great practical potential in wastewater treatment field.
基金partly supported by the National Natural Science Foundation of China(Nos.21577132,21978276)。
摘要Using low-cost precipitated silica(SiO2) as the carrier,a ternary SiO2-TiO2/g-C3N4 composite photocatalyst was prepared via the sol-gel method associated with a wet-grinding process.The asprepared composite exhibits photocatalytic hydrogen production and pollutant degradation performance under solar-like irradiation.The effect of SiO2 carrier on the properties of the heterostructure between TiO2 and g-C3N4(CN) was systematically studied.It is found that SiO2 has important effects on promoting the interaction between TiO2 and CN.The particle size of TiO2 and CN was obviously reduced during the calcination process due to the effects of SiO2.Especially,the TiO2 particles exhibit monodispersed state with particle size below 10 nm(quantum dots),resulting in the improvement of the contact area and the interaction betweenTiO2 and CN,and leading to the formation of efficient TiO2/CN Zscheme heterostructure in SiO2-TiO2/CN.Besides,the introduction of SiO2 can increase the specific surface area and light absorption of SiO2-TiO2/CN,further promoting the photocatalytic reaction.As expected,the optimum SiO2-TiO2/CN composite exhibits 12.3,3.1 and 2.9 times higher photocatalytic hydrogen production rate than that of SiO2-TiO2,CN and TiO2/CN under solar-like irradiation,while the photocatalytic active component in SiO2-TiO2/CN is only about 60 wt%.Moreover,the rhodamine B degradation rate of SiO2-TiO2/CN is also higher than that of SiO2-TiO2,CN and TiO2/CN.
基金Project(11JJ5010) supported by the Natural Science Foundation of Hunan Province, ChinaProject(2011RS4069) supported by the Planned Science and Technology Program of Hunan Province, ChinaProject supported by the Postdoctoral Science Foundation of Central South University,China
摘要The photo absorbing, photo transmitting and photoluminescence performances of WiO2 photocatalysts compounded with V2O5 or WO3 were investigated by UV-Vis spectra, transmitting spectra, and PL spectra, respectively. The energy band structures of TiO2 photocatalysts were analyzed. The photocatalytic activities of the TiO2 photocatalysts were investigated by splitting of water for 02 evolution. The results indicate that the band gaps of WO3 and V205 are about 2.8 and 2.14 eV, respectively, and the band gap of rutile TiO2 is about 3.08 eV. Speeds of water splitting for 2%WO3-TiO2 and 8%V2O5-TiO2 photocatalysts are 420 and 110 μmol/(L.h), respectively, under UV light irradiation. V2O5 and WO3 compounded with suitable concentration can improve the photocatalytic activity of TiO2 with Fe3+ as electron acceptor.