The electrochemistry of iron oxide thin films nanostructured by high ion flux plasma exposure

R. Sinha, I. Tanyeli, R. Lavrijsen, M.C.M. van de Sanden, A. Bieberle-Hütter

Onderzoeksoutput: Bijdrage aan tijdschriftTijdschriftartikelAcademicpeer review

5 Citaties (Scopus)
1 Downloads (Pure)

Uittreksel

Photo-electrochemical (PEC) water splitting of hematite photoanodes suffers from low performance and efficiency. One way to increase the performance is to increase the electrochemically active surface area available for the oxygen evolution reaction. In this study, we use high ion flux, low energy helium plasma exposure to nanostructure sputtered iron thin films. Subsequent annealing in air at 645 °C leads to the formation of PEC active hematite (α-Fe2O3) phase in these films. The surface area, as derived from electrochemical impedance spectroscopy (EIS), was seen to increase 10–40 times with plasma exposure. The photocurrent density increased by 2–5 times for the plasma exposed films as compared to the unexposed films. However, the less nanostructured film showed a higher photocurrent density. These findings were explained by detailed chemical and structural characterization in combination with electrochemical characterization and attributed to the presence of secondary elements in the film as well as to the presence of secondary iron oxide phases apart from hematite. This work demonstrates the complex effect of plasma exposure on both film morphology and chemical composition of PEC thin films and provides further understanding on how this technique can be used for nanostructuring of other functional films.

Originele taal-2Engels
Pagina's (van-tot)709-717
Aantal pagina's9
TijdschriftElectrochimica Acta
Volume258
DOI's
StatusGepubliceerd - 20 dec 2017

Vingerafdruk

Electrochemistry
Iron oxides
Oxide films
Ions
Fluxes
Plasmas
Thin films
Hematite
Photocurrents
Helium
ferric oxide
Electrochemical impedance spectroscopy
Nanostructures
Iron
Annealing
Oxygen
Water
Air
Chemical analysis

Citeer dit

@article{a29957fed3b249dbacbe36da2674bd16,
title = "The electrochemistry of iron oxide thin films nanostructured by high ion flux plasma exposure",
abstract = "Photo-electrochemical (PEC) water splitting of hematite photoanodes suffers from low performance and efficiency. One way to increase the performance is to increase the electrochemically active surface area available for the oxygen evolution reaction. In this study, we use high ion flux, low energy helium plasma exposure to nanostructure sputtered iron thin films. Subsequent annealing in air at 645 °C leads to the formation of PEC active hematite (α-Fe2O3) phase in these films. The surface area, as derived from electrochemical impedance spectroscopy (EIS), was seen to increase 10–40 times with plasma exposure. The photocurrent density increased by 2–5 times for the plasma exposed films as compared to the unexposed films. However, the less nanostructured film showed a higher photocurrent density. These findings were explained by detailed chemical and structural characterization in combination with electrochemical characterization and attributed to the presence of secondary elements in the film as well as to the presence of secondary iron oxide phases apart from hematite. This work demonstrates the complex effect of plasma exposure on both film morphology and chemical composition of PEC thin films and provides further understanding on how this technique can be used for nanostructuring of other functional films.",
keywords = "Electrochemical impedance spectroscopy, Hematite, Magnetron sputtering, Plasma exposure, Water splitting",
author = "R. Sinha and I. Tanyeli and R. Lavrijsen and {van de Sanden}, M.C.M. and A. Bieberle-H{\"u}tter",
year = "2017",
month = "12",
day = "20",
doi = "10.1016/j.electacta.2017.11.117",
language = "English",
volume = "258",
pages = "709--717",
journal = "Electrochimica Acta",
issn = "0013-4686",
publisher = "Elsevier",

}

The electrochemistry of iron oxide thin films nanostructured by high ion flux plasma exposure. / Sinha, R.; Tanyeli, I.; Lavrijsen, R.; van de Sanden, M.C.M.; Bieberle-Hütter, A.

In: Electrochimica Acta, Vol. 258, 20.12.2017, blz. 709-717.

Onderzoeksoutput: Bijdrage aan tijdschriftTijdschriftartikelAcademicpeer review

TY - JOUR

T1 - The electrochemistry of iron oxide thin films nanostructured by high ion flux plasma exposure

AU - Sinha, R.

AU - Tanyeli, I.

AU - Lavrijsen, R.

AU - van de Sanden, M.C.M.

AU - Bieberle-Hütter, A.

PY - 2017/12/20

Y1 - 2017/12/20

N2 - Photo-electrochemical (PEC) water splitting of hematite photoanodes suffers from low performance and efficiency. One way to increase the performance is to increase the electrochemically active surface area available for the oxygen evolution reaction. In this study, we use high ion flux, low energy helium plasma exposure to nanostructure sputtered iron thin films. Subsequent annealing in air at 645 °C leads to the formation of PEC active hematite (α-Fe2O3) phase in these films. The surface area, as derived from electrochemical impedance spectroscopy (EIS), was seen to increase 10–40 times with plasma exposure. The photocurrent density increased by 2–5 times for the plasma exposed films as compared to the unexposed films. However, the less nanostructured film showed a higher photocurrent density. These findings were explained by detailed chemical and structural characterization in combination with electrochemical characterization and attributed to the presence of secondary elements in the film as well as to the presence of secondary iron oxide phases apart from hematite. This work demonstrates the complex effect of plasma exposure on both film morphology and chemical composition of PEC thin films and provides further understanding on how this technique can be used for nanostructuring of other functional films.

AB - Photo-electrochemical (PEC) water splitting of hematite photoanodes suffers from low performance and efficiency. One way to increase the performance is to increase the electrochemically active surface area available for the oxygen evolution reaction. In this study, we use high ion flux, low energy helium plasma exposure to nanostructure sputtered iron thin films. Subsequent annealing in air at 645 °C leads to the formation of PEC active hematite (α-Fe2O3) phase in these films. The surface area, as derived from electrochemical impedance spectroscopy (EIS), was seen to increase 10–40 times with plasma exposure. The photocurrent density increased by 2–5 times for the plasma exposed films as compared to the unexposed films. However, the less nanostructured film showed a higher photocurrent density. These findings were explained by detailed chemical and structural characterization in combination with electrochemical characterization and attributed to the presence of secondary elements in the film as well as to the presence of secondary iron oxide phases apart from hematite. This work demonstrates the complex effect of plasma exposure on both film morphology and chemical composition of PEC thin films and provides further understanding on how this technique can be used for nanostructuring of other functional films.

KW - Electrochemical impedance spectroscopy

KW - Hematite

KW - Magnetron sputtering

KW - Plasma exposure

KW - Water splitting

UR - http://www.scopus.com/inward/record.url?scp=85038210506&partnerID=8YFLogxK

U2 - 10.1016/j.electacta.2017.11.117

DO - 10.1016/j.electacta.2017.11.117

M3 - Article

AN - SCOPUS:85038210506

VL - 258

SP - 709

EP - 717

JO - Electrochimica Acta

JF - Electrochimica Acta

SN - 0013-4686

ER -