Fe2O3 Blocking Layer Produced by Cyclic Voltammetry Leads to Improved Photoelectrochemical Performance of Hematite Nanorods

Poornajar M, Nguyen NT, Ahn HJ, Buechler M, Liu N, Kment S, Zbořil R, Yoo JE, Schmuki P (2019)

Publication Type: Journal article

Publication year: 2019

Journal

Surfaces MDPI

Book Volume: 2

Pages Range: 131-144

Journal Issue: 1

DOI: 10.3390/surfaces2010011

Abstract

Hematite is a low band gap, earth abundant semiconductor and it is considered to be a promising choice for photoelectrochemical water splitting. However, as a bulk material its efficiency is low because of excessive bulk, surface, and interface recombination. In the present work, we propose a strategy to prepare a hematite (alpha -Fe2O3) photoanode consisting of hematite nanorods grown onto an iron oxide blocking layer. This blocking layer is formed from a sputter deposited thin metallic iron film on fluorine doped tin oxide (FTO) by using cyclic voltammetry to fully convert the film into an anodic oxide. In a second step, hematite nanorods (NR) are grown onto the layer using a hydrothermal approach. In this geometry, the hematite sub-layer works as a barrier for electron back diffusion (a blocking layer). This suppresses recombination, and the maximum of the incident photon to current efficiency is increased from 12% to 17%. Under AM 1.5 conditions, the photocurrent density reaches approximately 1.2 mA/cm(2) at 1.5 V vs. RHE and the onset potential changes to 0.8 V vs. RHE (using a Zn-Co co-catalyst).

Authors with CRIS profile

Nhat Truong Nguyen Lehrstuhl für Werkstoffwissenschaften (Korrosion und Oberflächentechnik) Hyo-Jin Ahn Lehrstuhl für Werkstoffwissenschaften (Korrosion und Oberflächentechnik) Ning Liu Lehrstuhl für Werkstoffwissenschaften (Korrosion und Oberflächentechnik) Jeong Eun Yoo Lehrstuhl für Werkstoffwissenschaften (Korrosion und Oberflächentechnik) Patrik Schmuki Lehrstuhl für Werkstoffwissenschaften (Korrosion und Oberflächentechnik)

Involved external institutions

Regional Centre of Advanced Technologies and Materials CZ Czech Republic (CZ) Schweizerische Gesellschaft für Korrosionsschutz (SGK) CH Switzerland (CH)

How to cite

APA:

Poornajar, M., Nguyen, N.T., Ahn, H.-J., Buechler, M., Liu, N., Kment, S.,... Schmuki, P. (2019). Fe2O3 Blocking Layer Produced by Cyclic Voltammetry Leads to Improved Photoelectrochemical Performance of Hematite Nanorods. Surfaces, 2(1), 131-144. https://doi.org/10.3390/surfaces2010011

MLA:

Poornajar, Mahshid, et al. "Fe2O3 Blocking Layer Produced by Cyclic Voltammetry Leads to Improved Photoelectrochemical Performance of Hematite Nanorods." Surfaces 2.1 (2019): 131-144.

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