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Title: Enhanced photocatalytic performance in atomic layer deposition grown TiO{sub 2} thin films via hydrogen plasma treatment

Abstract

The authors report the effect of hydrogen plasma treatment on TiO{sub 2} thin films grown by atomic layer deposition as an effective approach for modifying the photoanode materials in order to enhance their photoelectrochemical performance. Hydrogen plasma treated TiO{sub 2} thin films showed an improved absorption in the visible spectrum probably due to surface reduction. XPS analysis confirmed the formation of Ti{sup 3+} states upon plasma treatment. Hydrogen plasma treatment of TiO{sub 2} films enhanced the measured photocurrent densities by a factor of 8 (1 mA/cm{sup 2} at 0.8 V versus normal hydrogen electrode) when compared to untreated TiO{sub 2} (0.12 mA/cm{sup 2}). The enhancement in photocurrent is attributed to the formation of localized electronic states in mid band-gap region, which facilitate efficient separation and transportation of photo excited charge carriers in the UV region of electromagnetic spectrum.

Authors:
; ; ;  [1];  [2]
  1. Institute of Inorganic Chemistry, University of Cologne, Greinstrasse 6, Cologne 50939 (Germany)
  2. Department of Chemistry, Technische Universität Berlin, Berlin 10623 (Germany)
Publication Date:
OSTI Identifier:
22392124
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Vacuum Science and Technology. A, Vacuum, Surfaces and Films; Journal Volume: 33; Journal Issue: 1; Other Information: (c) 2014 American Vacuum Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; 42 ENGINEERING; ABSORPTION; CHARGE CARRIERS; ELECTRODES; HYDROGEN; PERFORMANCE; PHOTOCATALYSIS; PLASMA; SURFACES; THIN FILMS; TITANIUM IONS; TITANIUM OXIDES; VISIBLE SPECTRA; X-RAY PHOTOELECTRON SPECTROSCOPY

Citation Formats

Sasinska, Alexander, Singh, Trilok, Wang, Shuangzhou, Mathur, Sanjay, E-mail: sanjay.mathur@uni-koeln.de, and Kraehnert, Ralph. Enhanced photocatalytic performance in atomic layer deposition grown TiO{sub 2} thin films via hydrogen plasma treatment. United States: N. p., 2015. Web. doi:10.1116/1.4904503.
Sasinska, Alexander, Singh, Trilok, Wang, Shuangzhou, Mathur, Sanjay, E-mail: sanjay.mathur@uni-koeln.de, & Kraehnert, Ralph. Enhanced photocatalytic performance in atomic layer deposition grown TiO{sub 2} thin films via hydrogen plasma treatment. United States. doi:10.1116/1.4904503.
Sasinska, Alexander, Singh, Trilok, Wang, Shuangzhou, Mathur, Sanjay, E-mail: sanjay.mathur@uni-koeln.de, and Kraehnert, Ralph. 2015. "Enhanced photocatalytic performance in atomic layer deposition grown TiO{sub 2} thin films via hydrogen plasma treatment". United States. doi:10.1116/1.4904503.
@article{osti_22392124,
title = {Enhanced photocatalytic performance in atomic layer deposition grown TiO{sub 2} thin films via hydrogen plasma treatment},
author = {Sasinska, Alexander and Singh, Trilok and Wang, Shuangzhou and Mathur, Sanjay, E-mail: sanjay.mathur@uni-koeln.de and Kraehnert, Ralph},
abstractNote = {The authors report the effect of hydrogen plasma treatment on TiO{sub 2} thin films grown by atomic layer deposition as an effective approach for modifying the photoanode materials in order to enhance their photoelectrochemical performance. Hydrogen plasma treated TiO{sub 2} thin films showed an improved absorption in the visible spectrum probably due to surface reduction. XPS analysis confirmed the formation of Ti{sup 3+} states upon plasma treatment. Hydrogen plasma treatment of TiO{sub 2} films enhanced the measured photocurrent densities by a factor of 8 (1 mA/cm{sup 2} at 0.8 V versus normal hydrogen electrode) when compared to untreated TiO{sub 2} (0.12 mA/cm{sup 2}). The enhancement in photocurrent is attributed to the formation of localized electronic states in mid band-gap region, which facilitate efficient separation and transportation of photo excited charge carriers in the UV region of electromagnetic spectrum.},
doi = {10.1116/1.4904503},
journal = {Journal of Vacuum Science and Technology. A, Vacuum, Surfaces and Films},
number = 1,
volume = 33,
place = {United States},
year = 2015,
month = 1
}
  • No abstract prepared.
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