1-Methyl-3-carboxymethyl imidazolium chlorine（\C2OOHmim\Cl） ionic liquid surface-capped TiO 2 nanoparticles were prepared by using tetra-n-butyl titanate ethanol solution as a precursor. The structure of nanoparticl...1-Methyl-3-carboxymethyl imidazolium chlorine（\C2OOHmim\Cl） ionic liquid surface-capped TiO 2 nanoparticles were prepared by using tetra-n-butyl titanate ethanol solution as a precursor. The structure of nanoparticles was characterized by FTIR, TEM, XRD and XPS. The results confirmed that \KG-1/5C2OOHmim\·Cl ionic liquid combined with TiO 2 nanoparticles by chelation, the average diameter of TiO 2 nanoparticles was about 8 nm and anatase state was obtained. And only anatase existed even after calcinated at 750 ℃. As to the formation mechanism, we think that the inorganic-organic copolymerized surface-capped layer and repulsive force of positive charge played an important role in the formation and stabilization of TiO 2 nanoparticles.展开更多
A facile and reproducible method has been developed for the synthesis of ordered anatase Mn-TiO2 nanospheres with controllable sizes in the range 200-300 nm by simply varying the amount of manganese（lI） chloride add...A facile and reproducible method has been developed for the synthesis of ordered anatase Mn-TiO2 nanospheres with controllable sizes in the range 200-300 nm by simply varying the amount of manganese（lI） chloride added. The samples were characterized by X-ray diffraction （XRD）, X-ray photoelectron spectroscopy （XPS）, scanning electron microscope （SEM）, and transmission electron microscope （TEM） measurements, and it was found that the manganese exists in multivalent forms （Mn4＋/Mn3＋） and substitutes for some of the Ti4＋ in the anatase TiO2 lattice. The presence of Mn significantly influences the morphology and high-temperature stability of TiO2, and extends its light absorption range. Surface photovoltage and photocurrent measurements revealed that an electronic interaction between the Mn and TiO2 was present, in which Mn served as an electron acceptor and effectively inhibited the charge recombination in TiO2; this is thought to be responsible for the highly efficient photocatalytic activity of the material in the degradation of rhodarnine B （RhB） under visible-light irradiation （λ 〉 420 nm）.展开更多
Uniquely structured rutile TiO2 microspheres with exposed nano-acicular single crystals have been successfully synthesized via a facile hydrothermal method. After calcination at 450 ℃ for 2 h, the futile TiO2 microsp...Uniquely structured rutile TiO2 microspheres with exposed nano-acicular single crystals have been successfully synthesized via a facile hydrothermal method. After calcination at 450 ℃ for 2 h, the futile TiO2 microspheres with a high surface area of 132 m2/g have been utilized as a light harvesting enhancement material for dye-sensitized solar cells （DSSCs）. The resultant DSSCs exhibit an overall light conversion efficiency of 8.41% for TiO2 photoanodes made of futile TiO2 microspheres and anatase TiO, nanoparticles （mass ratio of 1：1）, significantly higher than that of pure anatase TiO2 nanoparticle photoanodes of similar thickness （6.74%）. Such a significant improvement in performance can be attributed to the enhanced light harvesting capability and synergetic electron transfer effect. This is because the photoanodes made of futile TiO2 microsphere possess high refractive index which improves the light utilisation efficiency, suitable microsphere core sizes （450-800 nm） to effectively scatter visible light, high surface area for dye loading, and synergetic electron transfer effects between nanoparticulate anatase and nano-acicular futile single crystals phases giving high electron collection efficiency.展开更多
文摘1-Methyl-3-carboxymethyl imidazolium chlorine（\C2OOHmim\Cl） ionic liquid surface-capped TiO 2 nanoparticles were prepared by using tetra-n-butyl titanate ethanol solution as a precursor. The structure of nanoparticles was characterized by FTIR, TEM, XRD and XPS. The results confirmed that \KG-1/5C2OOHmim\·Cl ionic liquid combined with TiO 2 nanoparticles by chelation, the average diameter of TiO 2 nanoparticles was about 8 nm and anatase state was obtained. And only anatase existed even after calcinated at 750 ℃. As to the formation mechanism, we think that the inorganic-organic copolymerized surface-capped layer and repulsive force of positive charge played an important role in the formation and stabilization of TiO 2 nanoparticles.
基金This work was supported by National Program on Key Basic Research Project （973 Program） （No. 2007CB613303） and the National Natural Science Foundation of China （Nos. 20703020 and 20873053）.
文摘A facile and reproducible method has been developed for the synthesis of ordered anatase Mn-TiO2 nanospheres with controllable sizes in the range 200-300 nm by simply varying the amount of manganese（lI） chloride added. The samples were characterized by X-ray diffraction （XRD）, X-ray photoelectron spectroscopy （XPS）, scanning electron microscope （SEM）, and transmission electron microscope （TEM） measurements, and it was found that the manganese exists in multivalent forms （Mn4＋/Mn3＋） and substitutes for some of the Ti4＋ in the anatase TiO2 lattice. The presence of Mn significantly influences the morphology and high-temperature stability of TiO2, and extends its light absorption range. Surface photovoltage and photocurrent measurements revealed that an electronic interaction between the Mn and TiO2 was present, in which Mn served as an electron acceptor and effectively inhibited the charge recombination in TiO2; this is thought to be responsible for the highly efficient photocatalytic activity of the material in the degradation of rhodarnine B （RhB） under visible-light irradiation （λ 〉 420 nm）.
文摘Uniquely structured rutile TiO2 microspheres with exposed nano-acicular single crystals have been successfully synthesized via a facile hydrothermal method. After calcination at 450 ℃ for 2 h, the futile TiO2 microspheres with a high surface area of 132 m2/g have been utilized as a light harvesting enhancement material for dye-sensitized solar cells （DSSCs）. The resultant DSSCs exhibit an overall light conversion efficiency of 8.41% for TiO2 photoanodes made of futile TiO2 microspheres and anatase TiO, nanoparticles （mass ratio of 1：1）, significantly higher than that of pure anatase TiO2 nanoparticle photoanodes of similar thickness （6.74%）. Such a significant improvement in performance can be attributed to the enhanced light harvesting capability and synergetic electron transfer effect. This is because the photoanodes made of futile TiO2 microsphere possess high refractive index which improves the light utilisation efficiency, suitable microsphere core sizes （450-800 nm） to effectively scatter visible light, high surface area for dye loading, and synergetic electron transfer effects between nanoparticulate anatase and nano-acicular futile single crystals phases giving high electron collection efficiency.
