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Title: Enhanced photoelectrochemical activity of vertically aligned ZnO-coated TiO{sub 2} nanotubes

Abstract

Vertically aligned ZnO-TiO{sub 2} hetero-nanostructures constructed of anatase TiO{sub 2} nanotubes (NTs) and wurtzite ZnO coatings are fabricated by atomic layer deposition of ZnO coatings on electrochemical anodization formed TiO{sub 2} NTs, and their photoelectrochemical activities are studied through photoelectrochemical and electrochemical characterization. Compared with bare TiO{sub 2} NTs, the transient photocurrent increases to over 1.5-fold for the annealed ZnO-coated TiO{sub 2} NTs under visible illumination. The ZnO-coated TiO{sub 2} NTs also show a longer electron lifetime, a lower charge-transfer resistance and a more negative flat-band potential than the bare TiO{sub 2} NTs, confirming the improved photoelectrochemical activity due to the enhanced charge separation.

Authors:
; ; ; ; ;  [1]; ;  [2]
  1. Department of Optical Science and Engineering, Fudan University, Shanghai 200433 (China)
  2. Department of Electronic Engineering, East China Normal University, Shanghai 200241 (China)
Publication Date:
OSTI Identifier:
22283236
Resource Type:
Journal Article
Resource Relation:
Journal Name: Applied Physics Letters; Journal Volume: 104; Journal Issue: 5; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; 77 NANOSCIENCE AND NANOTECHNOLOGY; ANNEALING; ANODIZATION; COATINGS; COMPARATIVE EVALUATIONS; ELECTRIC CONDUCTIVITY; ELECTROCHEMISTRY; ELECTRONS; ILLUMINANCE; LIFETIME; NANOTUBES; PHOTOCURRENTS; POTENTIALS; TITANIUM OXIDES; TRANSIENTS; ZINC OXIDES

Citation Formats

Cai, Hua, Yang, Qin, You, Qinghu, Sun, Jian, Xu, Ning, Wu, Jiada, E-mail: jdwu@fudan.edu.cn, Hu, Zhigao, and Duan, Zhihua. Enhanced photoelectrochemical activity of vertically aligned ZnO-coated TiO{sub 2} nanotubes. United States: N. p., 2014. Web. doi:10.1063/1.4863852.
Cai, Hua, Yang, Qin, You, Qinghu, Sun, Jian, Xu, Ning, Wu, Jiada, E-mail: jdwu@fudan.edu.cn, Hu, Zhigao, & Duan, Zhihua. Enhanced photoelectrochemical activity of vertically aligned ZnO-coated TiO{sub 2} nanotubes. United States. doi:10.1063/1.4863852.
Cai, Hua, Yang, Qin, You, Qinghu, Sun, Jian, Xu, Ning, Wu, Jiada, E-mail: jdwu@fudan.edu.cn, Hu, Zhigao, and Duan, Zhihua. Mon . "Enhanced photoelectrochemical activity of vertically aligned ZnO-coated TiO{sub 2} nanotubes". United States. doi:10.1063/1.4863852.
@article{osti_22283236,
title = {Enhanced photoelectrochemical activity of vertically aligned ZnO-coated TiO{sub 2} nanotubes},
author = {Cai, Hua and Yang, Qin and You, Qinghu and Sun, Jian and Xu, Ning and Wu, Jiada, E-mail: jdwu@fudan.edu.cn and Hu, Zhigao and Duan, Zhihua},
abstractNote = {Vertically aligned ZnO-TiO{sub 2} hetero-nanostructures constructed of anatase TiO{sub 2} nanotubes (NTs) and wurtzite ZnO coatings are fabricated by atomic layer deposition of ZnO coatings on electrochemical anodization formed TiO{sub 2} NTs, and their photoelectrochemical activities are studied through photoelectrochemical and electrochemical characterization. Compared with bare TiO{sub 2} NTs, the transient photocurrent increases to over 1.5-fold for the annealed ZnO-coated TiO{sub 2} NTs under visible illumination. The ZnO-coated TiO{sub 2} NTs also show a longer electron lifetime, a lower charge-transfer resistance and a more negative flat-band potential than the bare TiO{sub 2} NTs, confirming the improved photoelectrochemical activity due to the enhanced charge separation.},
doi = {10.1063/1.4863852},
journal = {Applied Physics Letters},
number = 5,
volume = 104,
place = {United States},
year = {Mon Feb 03 00:00:00 EST 2014},
month = {Mon Feb 03 00:00:00 EST 2014}
}
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