In(OH)3 photocatalyst was prepared using ultrasonic hydrolysis precipitation followed by calcining at temperature lower than 160 ℃.The characterizations by XRD,DRS,TG-DSC,TEM and FTIR show that the solid is a cubic c...In(OH)3 photocatalyst was prepared using ultrasonic hydrolysis precipitation followed by calcining at temperature lower than 160 ℃.The characterizations by XRD,DRS,TG-DSC,TEM and FTIR show that the solid is a cubic crystal with 10—15 nm size,and has two band gaps,direct band gap 5.48 and indirect gap 5.02 eV.Evaluation of the photocatalytic activity toward oxidation reactions of benzene under UV irradiation(λmax=254 nm) showed that In(OH)3 presented much higher photoactivity and active stability than commercial Degussa-P25 TiO2.FTIR characterization for the samples before and after the photocatalytic reaction suggested that the better photocatalytic behavior of In(OH)3 than the TiO2 is due to lower aggradations of the intermediate species on its surface in photocatalytic process.展开更多
Photocatalytic degradation of paraquat (PQ) aqueous solutions was studied in a fixed bed photoreactor under UV irradiation at 368 nm. This contained β-SiC alveolar foams coated with TiO2 P25 by dip-coating method. SE...Photocatalytic degradation of paraquat (PQ) aqueous solutions was studied in a fixed bed photoreactor under UV irradiation at 368 nm. This contained β-SiC alveolar foams coated with TiO2 P25 by dip-coating method. SEM analyses revealed that the surface of the film did not exhibit cracks in the presence of TTIP as a binder in the TiO2 P25 suspension. The following parameters were studied in continuous mode operation: the flow rate in the reactor, the initial concentration of the paraquat, the pH of the solution, the weight of photocatalytic material with the number of foams in the reactor and the weight of the catalyst deposited onto the support. The results showed that by working under optimal operating conditions at natural pH (pH = 6.7), low paraquat (Co = 10 ppm), and flow (26 mL/min), we recorded approximately (43.16 ± 1.00)% oxidation of paraquat and a decrease in total organic carbon (TOC) of (27.13 ± 1.00)% after about 70 minutes. The apparent rate constant is in the order of (0.0656 ± 0.0010) min-1. In addition, by increasing the amount of β-SiC foams coated with TiO2, we improve the degradation of paraquat in the same order. The study of aging of the material showed its stability over time. However, photocatalytic activity was limited after 20 minutes of UV irradiation due to the limitation of the diffusion of the paraquat molecules towards the surface of the photocatalyst. As an outcome, we obtained an efficient TiO2/β-SiC material for photocatalytic degradation of organic compounds in water.展开更多
Pure anatase TiO2 films have been made via hydration of titanium isopropoxide using a sol-gel tech- nique, while mixed TiO2 films which contained both anatase and rutile TiO2 were made from commercial P25 powder. Quas...Pure anatase TiO2 films have been made via hydration of titanium isopropoxide using a sol-gel tech- nique, while mixed TiO2 films which contained both anatase and rutile TiO2 were made from commercial P25 powder. Quasi-solid state dye-sensitized solar cells were fabricated with these two kinds of mesoporous films and a comparison study was carried out. The result showed that the open-circuit photovoltages (Voc) for both kinds of cells were essentially the same, whereas the short-circuit photo- currents (Isc) of the anatase-based cells were about 33% higher than that of the P25-based cells. The highest photocurrent intensity of the anatase-based cell was 6.12 mA/cm2 and that of the P25-based cell was 4.60 mA/cm2. Under an illumination with the light intensity of 30 mW/cm2, the corresponding en- ergy conversion efficiency was measured to be 7.07% and 6.89% for anatase-based cells and P25-based cells, respectively.展开更多
Photodynamic therapy （PDT） is one of the latest biomedical technologies used for treatment of various neoplastic and non-neoplastic diseases. However, there still exist some well-known problems regarding its efficac...Photodynamic therapy （PDT） is one of the latest biomedical technologies used for treatment of various neoplastic and non-neoplastic diseases. However, there still exist some well-known problems regarding its efficacy, e.g. effective concentra- tion of the drug at the desired sites, the irradiation light dosimetry and biocompatibility of the photosensitizer. The introduction of nanotechnology and nanomaterial like biocompatible nano-titania （i.e., nano-TiO2） may facilitate to solve some of these problems. In this study we have explored the possibility of combining tetra sulphonatophenyl porphyrin （TSPP） with nano-titania （PT） for efficient PDT with least adverse effects. The spectroscopic properties of these nano-cornposites were characterized by using fluorescence and UV-Vis absorption spectroscopic study. The singlet oxygen quantum yield was deter- mined by using 2,5-diphenyl-3,4-benzofuran （DPBF）, while the effect of nano TiO2 with TSPP on the synovial fibroblast cells from human （HSC） and rat models （RSC） were investigated by confocal laser microscopy and 3-（4,5-dimethylthiazol-2-yl）- 2,5-diphenyltetrazolium bromide （MTT） assay. Our results suggest that nano TiO2 with TSPP can be readily utilized for effec- tive PDT treatment of Rheumatoid Arthritis （RA）.展开更多
The influence of NH3-treating temperature on the visible light photocatalytic activity of N-doped P25-TiO2 as well as the relationship between the surface composition structure of TiO2 and its visible light photocatal...The influence of NH3-treating temperature on the visible light photocatalytic activity of N-doped P25-TiO2 as well as the relationship between the surface composition structure of TiO2 and its visible light photocatalytic activity were investigated.The results showed that N-doped P25-TiO2 treated at 600℃ had the highest activity.The structure of P25-TiO2 was converted from anatase to rutile at 700℃.Moreover,no N-doping was detected at the surface of P25-TiO2.There was no simply linear relationship between the visible light photocatalytic activity and the concentration of doped nitrogen,and visible light absorption.The visible light photocatalytic activity of N-doped P25-TiO2 was mainly influenced by the synergistic action of the following factors:(i) the formation of the single-electron-trapped oxygen vacancies(denoted as Vo);(ii) the doped nitrogen on the surface of TiO2;(iii) the anatase TiO2 structure.展开更多
文摘In(OH)3 photocatalyst was prepared using ultrasonic hydrolysis precipitation followed by calcining at temperature lower than 160 ℃.The characterizations by XRD,DRS,TG-DSC,TEM and FTIR show that the solid is a cubic crystal with 10—15 nm size,and has two band gaps,direct band gap 5.48 and indirect gap 5.02 eV.Evaluation of the photocatalytic activity toward oxidation reactions of benzene under UV irradiation(λmax=254 nm) showed that In(OH)3 presented much higher photoactivity and active stability than commercial Degussa-P25 TiO2.FTIR characterization for the samples before and after the photocatalytic reaction suggested that the better photocatalytic behavior of In(OH)3 than the TiO2 is due to lower aggradations of the intermediate species on its surface in photocatalytic process.
文摘Photocatalytic degradation of paraquat (PQ) aqueous solutions was studied in a fixed bed photoreactor under UV irradiation at 368 nm. This contained β-SiC alveolar foams coated with TiO2 P25 by dip-coating method. SEM analyses revealed that the surface of the film did not exhibit cracks in the presence of TTIP as a binder in the TiO2 P25 suspension. The following parameters were studied in continuous mode operation: the flow rate in the reactor, the initial concentration of the paraquat, the pH of the solution, the weight of photocatalytic material with the number of foams in the reactor and the weight of the catalyst deposited onto the support. The results showed that by working under optimal operating conditions at natural pH (pH = 6.7), low paraquat (Co = 10 ppm), and flow (26 mL/min), we recorded approximately (43.16 ± 1.00)% oxidation of paraquat and a decrease in total organic carbon (TOC) of (27.13 ± 1.00)% after about 70 minutes. The apparent rate constant is in the order of (0.0656 ± 0.0010) min-1. In addition, by increasing the amount of β-SiC foams coated with TiO2, we improve the degradation of paraquat in the same order. The study of aging of the material showed its stability over time. However, photocatalytic activity was limited after 20 minutes of UV irradiation due to the limitation of the diffusion of the paraquat molecules towards the surface of the photocatalyst. As an outcome, we obtained an efficient TiO2/β-SiC material for photocatalytic degradation of organic compounds in water.
基金the National Basic Research Program of China (Grant No. 2002CB613405)the National Natural Science Foundation of China (Grant Nos. 50325310 and 50473009)
文摘Pure anatase TiO2 films have been made via hydration of titanium isopropoxide using a sol-gel tech- nique, while mixed TiO2 films which contained both anatase and rutile TiO2 were made from commercial P25 powder. Quasi-solid state dye-sensitized solar cells were fabricated with these two kinds of mesoporous films and a comparison study was carried out. The result showed that the open-circuit photovoltages (Voc) for both kinds of cells were essentially the same, whereas the short-circuit photo- currents (Isc) of the anatase-based cells were about 33% higher than that of the P25-based cells. The highest photocurrent intensity of the anatase-based cell was 6.12 mA/cm2 and that of the P25-based cell was 4.60 mA/cm2. Under an illumination with the light intensity of 30 mW/cm2, the corresponding en- ergy conversion efficiency was measured to be 7.07% and 6.89% for anatase-based cells and P25-based cells, respectively.
基金supported by the National Natural Science Foundation of China (81325011)National High Technology Research & Development Program of China (2015AA020502, 2012AA022703)+1 种基金the Major Science & Technology Project of Suzhou (ZXY2012028)the National Science Foundation CREST program (NSF HRD-0932421)
文摘Photodynamic therapy （PDT） is one of the latest biomedical technologies used for treatment of various neoplastic and non-neoplastic diseases. However, there still exist some well-known problems regarding its efficacy, e.g. effective concentra- tion of the drug at the desired sites, the irradiation light dosimetry and biocompatibility of the photosensitizer. The introduction of nanotechnology and nanomaterial like biocompatible nano-titania （i.e., nano-TiO2） may facilitate to solve some of these problems. In this study we have explored the possibility of combining tetra sulphonatophenyl porphyrin （TSPP） with nano-titania （PT） for efficient PDT with least adverse effects. The spectroscopic properties of these nano-cornposites were characterized by using fluorescence and UV-Vis absorption spectroscopic study. The singlet oxygen quantum yield was deter- mined by using 2,5-diphenyl-3,4-benzofuran （DPBF）, while the effect of nano TiO2 with TSPP on the synovial fibroblast cells from human （HSC） and rat models （RSC） were investigated by confocal laser microscopy and 3-（4,5-dimethylthiazol-2-yl）- 2,5-diphenyltetrazolium bromide （MTT） assay. Our results suggest that nano TiO2 with TSPP can be readily utilized for effec- tive PDT treatment of Rheumatoid Arthritis （RA）.
文摘The influence of NH3-treating temperature on the visible light photocatalytic activity of N-doped P25-TiO2 as well as the relationship between the surface composition structure of TiO2 and its visible light photocatalytic activity were investigated.The results showed that N-doped P25-TiO2 treated at 600℃ had the highest activity.The structure of P25-TiO2 was converted from anatase to rutile at 700℃.Moreover,no N-doping was detected at the surface of P25-TiO2.There was no simply linear relationship between the visible light photocatalytic activity and the concentration of doped nitrogen,and visible light absorption.The visible light photocatalytic activity of N-doped P25-TiO2 was mainly influenced by the synergistic action of the following factors:(i) the formation of the single-electron-trapped oxygen vacancies(denoted as Vo);(ii) the doped nitrogen on the surface of TiO2;(iii) the anatase TiO2 structure.
