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Title: Reactive Ballistic Deposition of Porous TiO2 Films: Growth and Characterization

Abstract

Nanoporous, high-surface area films of TiO2 are synthesized by reactive ballistic deposition of titanium metal in an oxygen ambient. Auger electron spectroscopy (AES) is used to investigate the stoichiometric dependence of the films on growth conditions (surface temperature and partial pressure of oxygen). Scanning and transmission electron microscopy show that the films consist of arrays of separated filaments. The surface area and the distribution of binding site energies of the films are measured as functions of growth temperature, deposition angle, and annealing conditions using temperature programmed desorption (TPD) of N2. TiO2 films deposited at 50 K at 70º from substrate normal display the greatest specific surface area of ~100 m2/g. In addition, the films retain greater than 70% of their original surface area after annealing to 600 K. The combination of high surface area and thermal stability suggest that these films could serve as supports for applications in heterogeneous catalysis.

Authors:
; ; ; ; ; ; ;
Publication Date:
Research Org.:
Pacific Northwest National Laboratory (PNNL), Richland, WA (US), Environmental Molecular Sciences Laboratory (EMSL)
Sponsoring Org.:
USDOE
OSTI Identifier:
908942
Report Number(s):
PNNL-SA-52580
17490; KC0302010; TRN: US200722%%824
DOE Contract Number:
AC05-76RL01830
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Physical Chemistry C, 111(12):4765-4773; Journal Volume: 111; Journal Issue: 12
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; TITANIUM OXIDES; DEPOSITION; FILMS; STOICHIOMETRY; CRYSTAL GROWTH; SURFACE AREA; ANNEALING; CATALYST SUPPORTS; Environmental Molecular Sciences Laboratory

Citation Formats

Flaherty, David W., Dohnalek, Zdenek, Dohnalkova, Alice, Arey, Bruce W., McCready, David E., Ponnusany, Nachimuthu, Mullins, C. Buddie, and Kay, Bruce D. Reactive Ballistic Deposition of Porous TiO2 Films: Growth and Characterization. United States: N. p., 2007. Web. doi:10.1021/jp067641m.
Flaherty, David W., Dohnalek, Zdenek, Dohnalkova, Alice, Arey, Bruce W., McCready, David E., Ponnusany, Nachimuthu, Mullins, C. Buddie, & Kay, Bruce D. Reactive Ballistic Deposition of Porous TiO2 Films: Growth and Characterization. United States. doi:10.1021/jp067641m.
Flaherty, David W., Dohnalek, Zdenek, Dohnalkova, Alice, Arey, Bruce W., McCready, David E., Ponnusany, Nachimuthu, Mullins, C. Buddie, and Kay, Bruce D. Thu . "Reactive Ballistic Deposition of Porous TiO2 Films: Growth and Characterization". United States. doi:10.1021/jp067641m.
@article{osti_908942,
title = {Reactive Ballistic Deposition of Porous TiO2 Films: Growth and Characterization},
author = {Flaherty, David W. and Dohnalek, Zdenek and Dohnalkova, Alice and Arey, Bruce W. and McCready, David E. and Ponnusany, Nachimuthu and Mullins, C. Buddie and Kay, Bruce D.},
abstractNote = {Nanoporous, high-surface area films of TiO2 are synthesized by reactive ballistic deposition of titanium metal in an oxygen ambient. Auger electron spectroscopy (AES) is used to investigate the stoichiometric dependence of the films on growth conditions (surface temperature and partial pressure of oxygen). Scanning and transmission electron microscopy show that the films consist of arrays of separated filaments. The surface area and the distribution of binding site energies of the films are measured as functions of growth temperature, deposition angle, and annealing conditions using temperature programmed desorption (TPD) of N2. TiO2 films deposited at 50 K at 70º from substrate normal display the greatest specific surface area of ~100 m2/g. In addition, the films retain greater than 70% of their original surface area after annealing to 600 K. The combination of high surface area and thermal stability suggest that these films could serve as supports for applications in heterogeneous catalysis.},
doi = {10.1021/jp067641m},
journal = {Journal of Physical Chemistry C, 111(12):4765-4773},
number = 12,
volume = 111,
place = {United States},
year = {Thu Mar 29 00:00:00 EDT 2007},
month = {Thu Mar 29 00:00:00 EDT 2007}
}
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  • Highly-porous (~90%), high-surface area (~1000 m2/g), thermally stable (1200K) crystalline films of MgO are synthesized using a novel reactive ballistic deposition techniques. The film consists of a tilted array of porous nanoscale crystalline filaments. Suprisingly, the individual filaments exhibit a high degree of crystallographic order with respect to each other. These films have chemical binding sites analogous to those on MgO (100). However, the fraction of chemically active, high energy binding sites is greatly enhanced on the nanoporous film. This unique collection of properties makes these materials attractive candidates for chemical applications such as sensors and heterogeneous catalysts.
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