Tailoring properties of nanostructured MoO3−x thin films by aqueous solution deposition

Katherine Inzani, Mohammadreza Nematollahi, Sverre M. Selbach, Tor Grande, Magnus Langøien Waalekalv, Thomas Brakstad, Turid Worren Reenaas, Morten Kildemo, Fride Vullum-Bruer (Corresponding Author)

Research output: Contribution to journalArticleAcademicpeer-review

1 Citation (Scopus)

Abstract

Molybdenum oxide films are required for a large range of optical, electronic and catalytic applications, and optimal film characteristics are similarly broad. Furthermore, the layered crystal structure of MoO3 is suited to nanostructuring, which can be adapted to enhance the film properties. Here, we present a simple, aqueous route to MoO3 thin films and attain nanostructured morphologies by control of solution parameters. Smooth and homogeneous thin films were achieved by control of the molecular species in solution by pH. The sensitivity of film quality to pH was demonstrated with the addition of PVA to the solution, which resulted in large spherical particulates on the surface. Film thickness was adjusted from 10 to 60 nm, whilst maintaining good film quality, by changing the solution concentration. Moreover, the grain size and nanocrystallite orientation varied with solution concentration. The importance of film morphology is revealed in the compositional changes of the films during hydrogen reduction, with differences in breakdown of film coverage and growth of reduced phases. Furthermore, spectroscopic ellipsometry was used to determine the optical properties of the films. This revealed changes in the dielectric function and band gap that were dependent on the level of reduction. The nanoscale morphologies presented demonstrate the potential to precisely control film morphology, dimensions, oxygen stoichiometry and phase composition by a low-cost wet chemical route.

Original languageEnglish
Pages (from-to)822-829
Number of pages8
JournalApplied surface science
Volume459
DOIs
Publication statusPublished - 30 Nov 2018
Externally publishedYes

Fingerprint

Thin films
Molybdenum oxide
Spectroscopic ellipsometry
Phase composition
Stoichiometry
Oxide films
Film thickness
Hydrogen
Energy gap
Optical properties
Crystal structure
Oxygen
Costs
molybdenum trioxide

Keywords

  • Nanostructured thin films
  • Optical properties
  • Solution processing
  • Molybdenum oxide

Cite this

Inzani, K., Nematollahi, M., Selbach, S. M., Grande, T., Waalekalv, M. L., Brakstad, T., ... Vullum-Bruer, F. (2018). Tailoring properties of nanostructured MoO3−x thin films by aqueous solution deposition. Applied surface science, 459, 822-829. https://doi.org/10.1016/j.apsusc.2018.07.196
Inzani, Katherine ; Nematollahi, Mohammadreza ; Selbach, Sverre M. ; Grande, Tor ; Waalekalv, Magnus Langøien ; Brakstad, Thomas ; Reenaas, Turid Worren ; Kildemo, Morten ; Vullum-Bruer, Fride. / Tailoring properties of nanostructured MoO3−x thin films by aqueous solution deposition. In: Applied surface science. 2018 ; Vol. 459. pp. 822-829.
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Inzani, K, Nematollahi, M, Selbach, SM, Grande, T, Waalekalv, ML, Brakstad, T, Reenaas, TW, Kildemo, M & Vullum-Bruer, F 2018, 'Tailoring properties of nanostructured MoO3−x thin films by aqueous solution deposition' Applied surface science, vol. 459, pp. 822-829. https://doi.org/10.1016/j.apsusc.2018.07.196

Tailoring properties of nanostructured MoO3−x thin films by aqueous solution deposition. / Inzani, Katherine; Nematollahi, Mohammadreza; Selbach, Sverre M.; Grande, Tor; Waalekalv, Magnus Langøien; Brakstad, Thomas; Reenaas, Turid Worren; Kildemo, Morten; Vullum-Bruer, Fride (Corresponding Author).

In: Applied surface science, Vol. 459, 30.11.2018, p. 822-829.

Research output: Contribution to journalArticleAcademicpeer-review

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AU - Inzani, Katherine

AU - Nematollahi, Mohammadreza

AU - Selbach, Sverre M.

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AU - Waalekalv, Magnus Langøien

AU - Brakstad, Thomas

AU - Reenaas, Turid Worren

AU - Kildemo, Morten

AU - Vullum-Bruer, Fride

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