The first-principles density-functional calculation was conducted to investigate the electronic band structures of titanium dioxide with heavy nitrogen doping （TiO2-xNx）.The calculation results indicate that when x...The first-principles density-functional calculation was conducted to investigate the electronic band structures of titanium dioxide with heavy nitrogen doping （TiO2-xNx）.The calculation results indicate that when x≤0.25,isolated N 2p states appear above the valence-band maximum of TiO2 without a band-gap narrowing between O 2p and Ti 3d states.When x≥0.50,an obvious band gap narrowing between O 2p and Ti 3d states was observed along with the existence of isolated N 2p states above the valence-band of TiO2,indicating that the mechanism proposed by Asahi et al operates under heavy nitrogen doping condition.展开更多
Nano-sized TiO2 doped La^3＋ , was used as photocatalysis to degrade polyethylene （PE） film in solid-state reaction. It made PE lose its mass fraction of 14.5%, and formed more quantities of CO2 and more wax yields ...Nano-sized TiO2 doped La^3＋ , was used as photocatalysis to degrade polyethylene （PE） film in solid-state reaction. It made PE lose its mass fraction of 14.5%, and formed more quantities of CO2 and more wax yields after UV irradiation for 288 h. SEM imagines displayed more and bigger holes and pits in the PE film. FT-IR spectra showed that there is a lower absorbance of groups of - CH2 and - CH3 in PE/ TiO2 and 0. 1% La2O3/TiO2/PE composite materials than that in PE film sample of photodegradation, and more carbonyl groups in PE/0.1% LaEO3/TiO2. La^3＋ doping TiO2 improves TiO2 activities of oxidation and erosion of PE film under UV irradiation.展开更多
基金Funded by the STC Program of the National Science Foundation(No.CTS-0120978)the Specialized Research Fund for the Doctoral Program of Higher Education(No.2005112001)the Natural Science Foundation of Shanxi Province(No.2006011051)
文摘The first-principles density-functional calculation was conducted to investigate the electronic band structures of titanium dioxide with heavy nitrogen doping （TiO2-xNx）.The calculation results indicate that when x≤0.25,isolated N 2p states appear above the valence-band maximum of TiO2 without a band-gap narrowing between O 2p and Ti 3d states.When x≥0.50,an obvious band gap narrowing between O 2p and Ti 3d states was observed along with the existence of isolated N 2p states above the valence-band of TiO2,indicating that the mechanism proposed by Asahi et al operates under heavy nitrogen doping condition.
文摘Nano-sized TiO2 doped La^3＋ , was used as photocatalysis to degrade polyethylene （PE） film in solid-state reaction. It made PE lose its mass fraction of 14.5%, and formed more quantities of CO2 and more wax yields after UV irradiation for 288 h. SEM imagines displayed more and bigger holes and pits in the PE film. FT-IR spectra showed that there is a lower absorbance of groups of - CH2 and - CH3 in PE/ TiO2 and 0. 1% La2O3/TiO2/PE composite materials than that in PE film sample of photodegradation, and more carbonyl groups in PE/0.1% LaEO3/TiO2. La^3＋ doping TiO2 improves TiO2 activities of oxidation and erosion of PE film under UV irradiation.
