Titanium dioxide(TiO 2) samples of different crystal forms were prepared by hydrolysis tetrabutyl titanate in various water to alkoxide ratios and sintering the hydrolysis product at different temperatures. The photo...Titanium dioxide(TiO 2) samples of different crystal forms were prepared by hydrolysis tetrabutyl titanate in various water to alkoxide ratios and sintering the hydrolysis product at different temperatures. The photocatalysts coated on hollow glass beads and loaded with platinum varying from 0.2% to 2.4% by weight.The photocatalytic degradation rate of sodium pentachlorophenolate (PCP-Na) depends on the preparing conditions such as: sintering temperatures, water to alkoxide ratios( R ), platinum content and the size. The proper conditions of preparation photocatalysts are as follows: the ratio of TiO 2 : sodium silicate : hollow glass beads : platinum is 10:5:20:0.15(w/w), R is 100, sintering temperature is 650℃, and the size of hollow glass is 0.5-1 mm. Under these conditions, the ratio between acatase and rutile of the photocatalyst is 2:1, and the photocatalytic activity is high.展开更多
Nanocrystalline TiO2 thin films were successfully prepared by a new “water-cooked” method on both conductive glass substrates and flexible substrates at low temperature. Dye-sensitized solar cells based on these fil...Nanocrystalline TiO2 thin films were successfully prepared by a new “water-cooked” method on both conductive glass substrates and flexible substrates at low temperature. Dye-sensitized solar cells based on these films have exhibited high overall light-to-electricity conversion efficiencies of 4.67 % and 1.94 % on conductive glass substrate and flexible substrate, respectively, under the illumination at 100 mW/cm2.展开更多
A Ni/TiO2（TBT） catalyst was prepared through in situ precipitation, using tetrabutyl titanate（TBT） as the TiO2 precursor, and was studied in CO methanation. A Ni catalyst supported on conunercial TiO2 was also pre...A Ni/TiO2（TBT） catalyst was prepared through in situ precipitation, using tetrabutyl titanate（TBT） as the TiO2 precursor, and was studied in CO methanation. A Ni catalyst supported on conunercial TiO2 was also prepared through post precipitation and studied to compare the influence of Ni precipitation conditions on the catalyst＇s performance. To gain insight on their structure and physicochemical properties, the catalysts were characterized with N2-adsorption, X-ray diffraction, transimission electron microscopy, H2 temperature programmed reduction and temperatttre programmed desorption. The results showed that the in situ precipitation method was beneficial to the dispersion of Ni and the formation of more active sites on the Ni/TiO2 catalyst. In addition, the density of the metal- support boundary and its interaction with the active component were also increased. These characteristics of Ni/TiO2（TBT） led to a lower light-off temperature and a suppression of Ni sintering during CO methanation. As a consequence, the Ni/TiO2（TBT） exhibited better catalytic behavior, with a CO conversion of 99.4% and CH4 selectivity of 90.4% tinder the following conditions： p=1 MPa, t=320℃, n（H2）/n（CO）=3, gas hour space velocity （GHSV）=2×10^4 mL·g^-1·h^-1. The life test results of the two catalysts showed that Ni/TiO2（TBT） was more stable and the catalytic activity remained at its initial level after being used for 30 h.展开更多
In this paper an improvement in the photocatalytic performance of TiO2 was carried out via hybridizing with graphene.Graphene-TiO2（GR-TiO2/nanocomposites with different weight addition ratios of graphene oxide（GO）h...In this paper an improvement in the photocatalytic performance of TiO2 was carried out via hybridizing with graphene.Graphene-TiO2（GR-TiO2/nanocomposites with different weight addition ratios of graphene oxide（GO）have been prepared via a facile microwave irradiation of GO and tetrabutyl titanate in isopropyl alcohol.Raman spectroscopy（RS）,X-ray diffraction（XRD）,scanning electron microscopy（SEM）,transmission electron microscopy（TEM）,UV–visible spectroscopy（UV–vis）,Fourier transform infrared spectra（FTIR）,energy dispersive X-ray spectroscopy（EDX）and photoluminescence spectra（PL）are employed to determine the properties of the samples.Microwave irradiation can heat the reactant to a higher temperature in a short time,simultaneously GO is reduced to graphene and TiO2 nanoparticles grown on the surface of GR.GR-TiO2 nanocomposites synthesized via this approach have efficient electron conductivity in GR,resulting in a reduced electron–hole recombination rate.Among the synthesized nanocomposites,GT-8wt% exhibited the best photocatalytic activity toward photocatalytic degradation of MB.Our current work provides a new insight for the fabrication of GR-TiO2 nanocomposites within a short reaction time and also explains the mechanism of photocatalysis employing radical and hole scavengers.展开更多
文摘Titanium dioxide(TiO 2) samples of different crystal forms were prepared by hydrolysis tetrabutyl titanate in various water to alkoxide ratios and sintering the hydrolysis product at different temperatures. The photocatalysts coated on hollow glass beads and loaded with platinum varying from 0.2% to 2.4% by weight.The photocatalytic degradation rate of sodium pentachlorophenolate (PCP-Na) depends on the preparing conditions such as: sintering temperatures, water to alkoxide ratios( R ), platinum content and the size. The proper conditions of preparation photocatalysts are as follows: the ratio of TiO 2 : sodium silicate : hollow glass beads : platinum is 10:5:20:0.15(w/w), R is 100, sintering temperature is 650℃, and the size of hollow glass is 0.5-1 mm. Under these conditions, the ratio between acatase and rutile of the photocatalyst is 2:1, and the photocatalytic activity is high.
基金The authors appreciate the generous financial support of this work by the Major State Basic Research Development Program(Grant No.G200028205)Innovative Foundation of the Chinese Academy of Science(Grant No.KGCX2-303-02)+1 种基金the National Natural Science Foundation of China(Grant No.50221201)High-Tech Research and Development of China Program(Grant No.2002 AA302403).
文摘Nanocrystalline TiO2 thin films were successfully prepared by a new “water-cooked” method on both conductive glass substrates and flexible substrates at low temperature. Dye-sensitized solar cells based on these films have exhibited high overall light-to-electricity conversion efficiencies of 4.67 % and 1.94 % on conductive glass substrate and flexible substrate, respectively, under the illumination at 100 mW/cm2.
基金Supported by the National Natural Science Foundation of China（No. 51661145011）, the National Science and Technology Supporting Plan, China（No.2015BAD 15B06）, the Foundation of the State Key Laboratory of Clean Energy Utilization, China（No. ZJUCEU2016001 ）.
文摘A Ni/TiO2（TBT） catalyst was prepared through in situ precipitation, using tetrabutyl titanate（TBT） as the TiO2 precursor, and was studied in CO methanation. A Ni catalyst supported on conunercial TiO2 was also prepared through post precipitation and studied to compare the influence of Ni precipitation conditions on the catalyst＇s performance. To gain insight on their structure and physicochemical properties, the catalysts were characterized with N2-adsorption, X-ray diffraction, transimission electron microscopy, H2 temperature programmed reduction and temperatttre programmed desorption. The results showed that the in situ precipitation method was beneficial to the dispersion of Ni and the formation of more active sites on the Ni/TiO2 catalyst. In addition, the density of the metal- support boundary and its interaction with the active component were also increased. These characteristics of Ni/TiO2（TBT） led to a lower light-off temperature and a suppression of Ni sintering during CO methanation. As a consequence, the Ni/TiO2（TBT） exhibited better catalytic behavior, with a CO conversion of 99.4% and CH4 selectivity of 90.4% tinder the following conditions： p=1 MPa, t=320℃, n（H2）/n（CO）=3, gas hour space velocity （GHSV）=2×10^4 mL·g^-1·h^-1. The life test results of the two catalysts showed that Ni/TiO2（TBT） was more stable and the catalytic activity remained at its initial level after being used for 30 h.
基金financial support of this research by the University Grants Commission (UGC)
文摘In this paper an improvement in the photocatalytic performance of TiO2 was carried out via hybridizing with graphene.Graphene-TiO2（GR-TiO2/nanocomposites with different weight addition ratios of graphene oxide（GO）have been prepared via a facile microwave irradiation of GO and tetrabutyl titanate in isopropyl alcohol.Raman spectroscopy（RS）,X-ray diffraction（XRD）,scanning electron microscopy（SEM）,transmission electron microscopy（TEM）,UV–visible spectroscopy（UV–vis）,Fourier transform infrared spectra（FTIR）,energy dispersive X-ray spectroscopy（EDX）and photoluminescence spectra（PL）are employed to determine the properties of the samples.Microwave irradiation can heat the reactant to a higher temperature in a short time,simultaneously GO is reduced to graphene and TiO2 nanoparticles grown on the surface of GR.GR-TiO2 nanocomposites synthesized via this approach have efficient electron conductivity in GR,resulting in a reduced electron–hole recombination rate.Among the synthesized nanocomposites,GT-8wt% exhibited the best photocatalytic activity toward photocatalytic degradation of MB.Our current work provides a new insight for the fabrication of GR-TiO2 nanocomposites within a short reaction time and also explains the mechanism of photocatalysis employing radical and hole scavengers.
