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Title: Room temperature alcohol sensing by oxygen vacancy controlled TiO{sub 2} nanotube array

Abstract

Oxygen vacancy (OV) controlled TiO{sub 2} nanotubes, having diameters of 50–70 nm and lengths of 200–250 nm, were synthesized by electrochemical anodization in the mixed electrolyte comprising NH{sub 4}F and ethylene glycol with selective H{sub 2}O content. The structural evolution of TiO{sub 2} nanoforms has been studied by field emission scanning electron microscopy. Variation in the formation of OVs with the variation of the structure of TiO{sub 2} nanoforms has been evaluated by photoluminescence and X-ray photoelectron spectroscopy. The sensor characteristics were correlated to the variation of the amount of induced OVs in the nanotubes. The efficient room temperature sensing achieved by the control of OVs of TiO{sub 2} nanotube array has paved the way for developing fast responding alcohol sensor with corresponding response magnitude of 60.2%, 45.3%, and 36.5% towards methanol, ethanol, and 2-propanol, respectively.

Authors:
; ; ;  [1];  [2]
  1. Nano-Thin Films and Solid State Gas Sensor Devices Laboratory, Department of Electronics and Telecommunication Engineering, Indian Institute of Engineering Science and Technology (IIEST), Shibpur, Howrah (India)
  2. Department of Metallurgy and Materials Engineering, Indian Institute of Engineering Science and Technology (IIEST), Shibpur, Howrah (India)
Publication Date:
OSTI Identifier:
22310941
Resource Type:
Journal Article
Resource Relation:
Journal Name: Applied Physics Letters; Journal Volume: 105; Journal Issue: 8; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
77 NANOSCIENCE AND NANOTECHNOLOGY; ALCOHOLS; AMMONIUM FLUORIDES; ANODIZATION; ELECTROCHEMISTRY; ELECTROLYTES; ETHANOL; FIELD EMISSION; METHANOL; NANOTUBES; OXYGEN; PHOTOLUMINESCENCE; PROPANOLS; SCANNING ELECTRON MICROSCOPY; SENSORS; TEMPERATURE RANGE 0273-0400 K; TITANIUM OXIDES; VACANCIES; WATER; X-RAY PHOTOELECTRON SPECTROSCOPY

Citation Formats

Hazra, A., Dutta, K., Bhowmik, B., Bhattacharyya, P., E-mail: pb-etc-besu@yahoo.com, and Chattopadhyay, P. P. Room temperature alcohol sensing by oxygen vacancy controlled TiO{sub 2} nanotube array. United States: N. p., 2014. Web. doi:10.1063/1.4894008.
Hazra, A., Dutta, K., Bhowmik, B., Bhattacharyya, P., E-mail: pb-etc-besu@yahoo.com, & Chattopadhyay, P. P. Room temperature alcohol sensing by oxygen vacancy controlled TiO{sub 2} nanotube array. United States. doi:10.1063/1.4894008.
Hazra, A., Dutta, K., Bhowmik, B., Bhattacharyya, P., E-mail: pb-etc-besu@yahoo.com, and Chattopadhyay, P. P. Mon . "Room temperature alcohol sensing by oxygen vacancy controlled TiO{sub 2} nanotube array". United States. doi:10.1063/1.4894008.
@article{osti_22310941,
title = {Room temperature alcohol sensing by oxygen vacancy controlled TiO{sub 2} nanotube array},
author = {Hazra, A. and Dutta, K. and Bhowmik, B. and Bhattacharyya, P., E-mail: pb-etc-besu@yahoo.com and Chattopadhyay, P. P.},
abstractNote = {Oxygen vacancy (OV) controlled TiO{sub 2} nanotubes, having diameters of 50–70 nm and lengths of 200–250 nm, were synthesized by electrochemical anodization in the mixed electrolyte comprising NH{sub 4}F and ethylene glycol with selective H{sub 2}O content. The structural evolution of TiO{sub 2} nanoforms has been studied by field emission scanning electron microscopy. Variation in the formation of OVs with the variation of the structure of TiO{sub 2} nanoforms has been evaluated by photoluminescence and X-ray photoelectron spectroscopy. The sensor characteristics were correlated to the variation of the amount of induced OVs in the nanotubes. The efficient room temperature sensing achieved by the control of OVs of TiO{sub 2} nanotube array has paved the way for developing fast responding alcohol sensor with corresponding response magnitude of 60.2%, 45.3%, and 36.5% towards methanol, ethanol, and 2-propanol, respectively.},
doi = {10.1063/1.4894008},
journal = {Applied Physics Letters},
number = 8,
volume = 105,
place = {United States},
year = {Mon Aug 25 00:00:00 EDT 2014},
month = {Mon Aug 25 00:00:00 EDT 2014}
}
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