Exploring the Spatial Distribution and Transport Behavior of Charge Carriers in a Single Titania Nanowire

被引:89
作者
Tachikawa, Takashi [1 ]
Majima, Tetsuro [1 ]
机构
[1] Osaka Univ, SANKEN, Inst Sci & Ind Res, Osaka 5670047, Japan
关键词
TIO2 NANOTUBE ARRAYS; OXIDE SEMICONDUCTOR-FILMS; BAND-EDGE MOVEMENT; SOLAR-CELLS; ELECTRON-TRANSPORT; QUANTUM-DOT; SPECTROSCOPIC DETERMINATION; RECOMBINATION KINETICS; SURFACE-STATES; PHOTOLUMINESCENCE;
D O I
10.1021/ja900194m
中图分类号
O6 [化学];
学科分类号
0703 ;
摘要
One-dimensional nanostructures of metal oxide semiconductors have both potential and demonstrated applications for use in light waveguides, photodetectors, solar energy conversion, photocatalysis, etc. We investigated the transport and reaction dynamics of the photogenerated charge carriers in individual titania nanowires using single-particle photoluminescence (PL) spectroscopy. Examination of the spectral and kinetic characteristics revealed that the photoluminescence bands originating from defects in the bulk and/or on the surface appeared in the visible region with numerous photon bursts by photoirradiation using a 405-nm laser under an At atmosphere. From the single-molecule kinetic analysis of the bursts, it was found that the quenching reaction of trapped electrons by molecular oxygen follows a Langmuir-Hinshelwood mechanism. In addition, a novel spectroscopic method, i.e., single-molecule spectroelectrochemistry, was utilized to explore the nature of the defect states inherent in the wires. The spatially resolved PL imaging techniques thus enable us to ascertain the location of the luminescent active sites that are related to the heterogeneously distributed defects and to present experimental evidence of the long-distance transport of charge carriers in the wire. Consequently, this study provides a great opportunity to understand the role of defects in the behavior of charge carriers in TiO2 nanomaterials with various morphologies.
引用
收藏
页码:8485 / 8495
页数:11
相关论文
共 89 条
[81]  
2-W
[82]   Photoinduced fluorescence enhancement in mono- and multilayer films of CdSe/ZnS quantum dots: Dependence on intensity and wavelength of excitation light [J].
Uematsu, T ;
Maenosono, S ;
Yamaguchi, Y .
JOURNAL OF PHYSICAL CHEMISTRY B, 2005, 109 (18) :8613-8618
[83]   Photoelectrochemical study on charge transfer properties of TiO2-B nanowires with an application as humidity sensors [J].
Wang, Geng ;
Wang, Qiang ;
Lu, Wu ;
Li, Jinghong .
JOURNAL OF PHYSICAL CHEMISTRY B, 2006, 110 (43) :22029-22034
[84]   Highly polarized photoluminescence and photodetection from single indium phosphide nanowires [J].
Wang, JF ;
Gudiksen, MS ;
Duan, XF ;
Cui, Y ;
Lieber, CM .
SCIENCE, 2001, 293 (5534) :1455-1457
[85]   Multicolor luminescence patterning by photoactivation of semiconductor nanoparticle films [J].
Wang, Y ;
Tang, ZY ;
Correa-Duarte, MA ;
Liz-Marzán, LM ;
Kotov, NA .
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY, 2003, 125 (10) :2830-2831
[86]   A solution-phase, precursor route to polycrystalline SnO2 nanowires that can be used for gas sensing under ambient conditions [J].
Wang, YL ;
Jiang, XC ;
Xia, YN .
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY, 2003, 125 (52) :16176-16177
[87]   Intensity-dependent relaxation of photoconductivity in nanocrystalline titania thin films [J].
Xie, Z ;
Burlakov, VM ;
Henry, BM ;
Kirov, KR ;
Smith, HE ;
Grovenor, CRM ;
Assender, HE ;
Briggs, GAD ;
Kano, M ;
Tsukahara, Y .
PHYSICAL REVIEW B, 2006, 73 (11)
[88]   Removing structural disorder from oriented TiO2 nanotube arrays:: Reducing the dimensionality of transport and recombination in dye-sensitized solar cells [J].
Zhu, Kai ;
Vinzant, Todd B. ;
Neale, Nathan R. ;
Frank, Arthur J. .
NANO LETTERS, 2007, 7 (12) :3739-3746
[89]   Enhanced charge-collection efficiencies and light scattering in dye-sensitized solar cells using oriented TiO2 nanotubes arrays [J].
Zhu, Kai ;
Neale, Nathan R. ;
Miedaner, Alexander ;
Frank, Arthur J. .
NANO LETTERS, 2007, 7 (01) :69-74