Near band-edge electron diffusion in electrospun Nb-doped anatase TiO2 nanofibers probed by electrochemical impedance spectroscopy

被引：31

作者：

Archana, P. S. ^{[1
]}

Jose, R. ^{[2
]}

Yusoff, M. M. ^{[2
]}

Ramakrishna, S. ^{[1
]}

机构：

[1] Natl Univ Singapore, Nanosci & Nanotechnol Initiat, Singapore 117576, Singapore

[2] Univ Malaysia Pahang, Fac Ind Sci & Technol, Kuantan 26300, Malaysia

来源：

APPLIED PHYSICS LETTERS | 2011年 / 98卷 / 15期

基金：

新加坡国家研究基金会;

关键词：

SENSITIZED SOLAR-CELLS; FILM ELECTRODES; METAL; SEMICONDUCTORS; CAPACITANCE; DENSITY;

D O I：

10.1063/1.3579194

中图分类号：

O59 [应用物理学];

学科分类号：

摘要：

Charge transport through Nb-doped anatase TiO2 nanofibers (diameter similar to 100 nm) developed by electrospinning is studied under the framework of hopping transport using electrochemical impedance spectroscopy measurements. It is observed that the Fermi level of TiO2 rise close to its conduction band and result in a band-edge type diffusion mechanism even at low bias voltages when 2 at % Nb atoms replaces the Ti atoms in the anatase lattice. The Nb-doped anatase electrospun nanofibers showed high chemical capacitance, high effective diffusion coefficient, and lower transport resistance compared to the undoped samples and conventional nanoparticles (25 nm). (C) 2011 American Institute of Physics. [doi:10.1063/1.3579194]

引用

页数：3

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