Issue 11, 2019

Anisotropy control in magnetic nanostructures through field-assisted chemical vapor deposition

Abstract

Chemical vapor deposition of iron pentacarbonyl (Fe(CO)5) in an external magnetic field (B = 1.00 T) was found to significantly affect the microstructure and anisotropy of as-deposited iron crystallites that could be transformed into anisotropic hematite (α-Fe2O3) nanorods by aerobic oxidation. The deterministic influence of external magnetic fields on CVD deposits was found to be substrate-independent as demonstrated by the growth of anisotropic α-Fe columns on FTO (F:SnO2) and Si (100), whereas the films deposited in the absence of the magnetic field were constituted by isotropic grains. TEM images revealed gradual increase in average crystallite size in correlation to the increasing field strength and orientation, which indicates the potential of magnetic field-assisted chemical vapor deposition (mfCVD) in controlling the texture of the CVD grown thin films. Given the facet-dependent activity of hematite in forming surface-oxygenated intermediates, exposure of crystalline facets and planes with high atomic density and electron mobilities is crucial for oxygen evolution reactions. The field-induced anisotropy in iron nanocolumns acting as templates for growing textured hematite pillars resulted in two-fold higher photoelectrochemical efficiency for hematite films grown under external magnetic fields (J = 0.050 mA cm−2), when compared to films grown in zero field (J = 0.027 mA cm−2). The dark current measurements indicated faster surface kinetics as the origin of the increased catalytic activity.

Graphical abstract: Anisotropy control in magnetic nanostructures through field-assisted chemical vapor deposition

Supplementary files

Article information

Article type
Communication
Submitted
31 Jul 2019
Accepted
25 Sep 2019
First published
17 Oct 2019
This article is Open Access
Creative Commons BY-NC license

Nanoscale Adv., 2019,1, 4290-4295

Anisotropy control in magnetic nanostructures through field-assisted chemical vapor deposition

D. Stadler, T. Brede, D. Schwarzbach, F. Maccari, T. Fischer, O. Gutfleisch, C. A. Volkert and S. Mathur, Nanoscale Adv., 2019, 1, 4290 DOI: 10.1039/C9NA00467J

This article is licensed under a Creative Commons Attribution-NonCommercial 3.0 Unported Licence. You can use material from this article in other publications, without requesting further permission from the RSC, provided that the correct acknowledgement is given and it is not used for commercial purposes.

To request permission to reproduce material from this article in a commercial publication, please go to the Copyright Clearance Center request page.

If you are an author contributing to an RSC publication, you do not need to request permission provided correct acknowledgement is given.

If you are the author of this article, you do not need to request permission to reproduce figures and diagrams provided correct acknowledgement is given. If you want to reproduce the whole article in a third-party commercial publication (excluding your thesis/dissertation for which permission is not required) please go to the Copyright Clearance Center request page.

Read more about how to correctly acknowledge RSC content.

Social activity

Spotlight

Advertisements