Atomic layer deposition of metastable β-Fe₂O₃ via isomorphic epitaxy for photoassisted water oxidation

Jonathan D Emery; Christian M Schlepütz; Peijun Guo; Shannon C Riha; Robert P H Chang; Alex B F Martinson

doi:10.1021/am507065y

Atomic layer deposition of metastable β-Fe₂O₃ via isomorphic epitaxy for photoassisted water oxidation

ACS Appl Mater Interfaces. 2014 Dec 24;6(24):21894-900. doi: 10.1021/am507065y. Epub 2014 Dec 9.

Authors

Jonathan D Emery¹, Christian M Schlepütz, Peijun Guo, Shannon C Riha, Robert P H Chang, Alex B F Martinson

Affiliation

¹ Materials Science Division and ‡X-ray Science Division, Argonne National Laboratory , 9700 South Cass Avenue, Argonne, Illinois 60439, United States.

PMID: 25490778
DOI: 10.1021/am507065y

Abstract

We report the growth and photoelectrochemical (PEC) characterization of the uncommon bibyite phase of iron(III) oxide (β-Fe2O3) epitaxially stabilized via atomic layer deposition on an conductive, transparent, and isomorphic template (Sn-doped In2O3). As a photoanode, unoptimized β-Fe2O3 ultrathin films perform similarly to their ubiquitous α-phase (hematite) counterpart, but reveal a more ideal bandgap (1.8 eV), a ∼0.1 V improved photocurrent onset potential, and longer wavelength (>600 nm) spectral response. Stable operation under basic water oxidation justifies further exploration of this atypical phase and motivates the investigation of other unexplored metastable phases as new PEC materials.

Keywords: PEC water oxidation; atomic layer deposition; epitaxial stabilization; iron(III) oxide; α-Fe2O3; β-Fe2O3.

Publication types

Letter
Research Support, Non-U.S. Gov't
Research Support, U.S. Gov't, Non-P.H.S.