A kind of photoelectrode was innovated by anodising titanium mesh in H 2SO 4 solution and photo reduced in HAuCl 4 solution and named Ti/Au TiO 2 mesh electrode. The structural and surface morphology of the Ti/Au TiO ...A kind of photoelectrode was innovated by anodising titanium mesh in H 2SO 4 solution and photo reduced in HAuCl 4 solution and named Ti/Au TiO 2 mesh electrode. The structural and surface morphology of the Ti/Au TiO 2 mesh was examined by X ray diffraction, laser Raman spectra, scanning electronic microscopy(SEM) and X ray photoelectron spectroscopy respectively. The results indicate that its crystal structure, morphology and the size of pore are affected greatly by gold deposition. XPS measurement shows that the valence band of Ti/TiO 2 has two peaks: a wide one at 4.97 eV and a narrow one at 6.61 eV, which correspond mainly to π(nonbonding) and σ (bonding) O 2p orbitals. The emission intensity of O 2p orbitals becomes stronger and the width of the valence band increases with the increase of Au content. And the emission of nonbonding shifts toward lower binding energy and that of bonding O 2p orbitals shifts toward higher binding energy. The photoelectrocatalytic(PEC) oxidation of humic acid(HA) was investigated in terms of TOC. The PEC oxidation efficiency of Ti/Au TiO 2 mesh with optimal content of gold is higher than that of Ti/TiO 2 mesh. It is suggested that the recombination of electrons and holes is hindered owing to gold deposition. The investigation shows that PEC oxidation is a convenient way to mineralize organic matter for water treatment.展开更多
This paper reports that single-layer and graded Au-TiO2 granular composite films with Au atom content 15%- 66% were prepared by using reactive co-sputtering technique. The third-order optical nonlinearity of single-la...This paper reports that single-layer and graded Au-TiO2 granular composite films with Au atom content 15%- 66% were prepared by using reactive co-sputtering technique. The third-order optical nonlinearity of single-layer and graded composite films was investigated by using s- and p-polarized Z-scans in femtosecond time scale. The nonlinear absorption coefficient βeff of single-layer Au-TiO2 films is measured to be -2.3×10^3-0.76×10^3 cm/GW with Au atom content 15%-66%. The βeff value of the 10-layer Au-TiO2 graded film is enhanced to be -2.1×10^4cm/GW calculated from p-polarized Z-scans, which is about ten times the maximum βeff of single-layer films. Broadened response in the wavelength region 730-860 nm of the enhanced optical nonlinearity of graded Au-TiO2 composite films was also investigated.展开更多
In this work, we developed a templated self-assembly approach to fabricate self-supporting Au/TiO2 binary nanoparticles-nanotubes （NPNTs） for the first time. The stable Au/TiO2 nanoparticles colloids were pre-synthe...In this work, we developed a templated self-assembly approach to fabricate self-supporting Au/TiO2 binary nanoparticles-nanotubes （NPNTs） for the first time. The stable Au/TiO2 nanoparticles colloids were pre-synthesized and then deposited onto an AAO template, following by a mild calcination process. Au/TiO2 binary NPNTs can be achieved after removing the AAO template by NaOH solution. In addition, Au/TiO2 NPNTs with different thicknesses and size distributions could be achieved by tailoring the process parameters, such as the molar ratio of AuNPs to TiO2NPs, deposition modes and calcinations conditions. Therefore, these findings made controllable formation of Au/TiO2 NPNTs attractive for promising fabrication methodologies of metal/metal oxides NPNTs.展开更多
文摘A kind of photoelectrode was innovated by anodising titanium mesh in H 2SO 4 solution and photo reduced in HAuCl 4 solution and named Ti/Au TiO 2 mesh electrode. The structural and surface morphology of the Ti/Au TiO 2 mesh was examined by X ray diffraction, laser Raman spectra, scanning electronic microscopy(SEM) and X ray photoelectron spectroscopy respectively. The results indicate that its crystal structure, morphology and the size of pore are affected greatly by gold deposition. XPS measurement shows that the valence band of Ti/TiO 2 has two peaks: a wide one at 4.97 eV and a narrow one at 6.61 eV, which correspond mainly to π(nonbonding) and σ (bonding) O 2p orbitals. The emission intensity of O 2p orbitals becomes stronger and the width of the valence band increases with the increase of Au content. And the emission of nonbonding shifts toward lower binding energy and that of bonding O 2p orbitals shifts toward higher binding energy. The photoelectrocatalytic(PEC) oxidation of humic acid(HA) was investigated in terms of TOC. The PEC oxidation efficiency of Ti/Au TiO 2 mesh with optimal content of gold is higher than that of Ti/TiO 2 mesh. It is suggested that the recombination of electrons and holes is hindered owing to gold deposition. The investigation shows that PEC oxidation is a convenient way to mineralize organic matter for water treatment.
基金Project supported by the National Natural Science Foundation of China (Grant No 10474075)
文摘This paper reports that single-layer and graded Au-TiO2 granular composite films with Au atom content 15%- 66% were prepared by using reactive co-sputtering technique. The third-order optical nonlinearity of single-layer and graded composite films was investigated by using s- and p-polarized Z-scans in femtosecond time scale. The nonlinear absorption coefficient βeff of single-layer Au-TiO2 films is measured to be -2.3×10^3-0.76×10^3 cm/GW with Au atom content 15%-66%. The βeff value of the 10-layer Au-TiO2 graded film is enhanced to be -2.1×10^4cm/GW calculated from p-polarized Z-scans, which is about ten times the maximum βeff of single-layer films. Broadened response in the wavelength region 730-860 nm of the enhanced optical nonlinearity of graded Au-TiO2 composite films was also investigated.
基金supports provided by National Natural Science Foundation of China(No. 51104194)Doctoral Fund of Ministry of Education of China(No. 20110191120014)+1 种基金No.43 Scientific Research Foundation for the Returned Overseas Chinese ScholarsState Education Ministry and Fundamental Research Funds for the Central Universities(Nos. CDJZR13130035,CDJZR12248801 and CDJZR12135501.Chongqing University,China)
文摘In this work, we developed a templated self-assembly approach to fabricate self-supporting Au/TiO2 binary nanoparticles-nanotubes （NPNTs） for the first time. The stable Au/TiO2 nanoparticles colloids were pre-synthesized and then deposited onto an AAO template, following by a mild calcination process. Au/TiO2 binary NPNTs can be achieved after removing the AAO template by NaOH solution. In addition, Au/TiO2 NPNTs with different thicknesses and size distributions could be achieved by tailoring the process parameters, such as the molar ratio of AuNPs to TiO2NPs, deposition modes and calcinations conditions. Therefore, these findings made controllable formation of Au/TiO2 NPNTs attractive for promising fabrication methodologies of metal/metal oxides NPNTs.
