Hybrid FeNiOOH/α-Fe 2 O 3 /Graphene Photoelectrodes with Advanced Water Oxidation Performance.

Autor: Kormányos A; Department of Physical Chemistry and Materials Science University of Szeged Szeged H-6720 Hungary., Kecsenovity E; Department of Physical Chemistry and Materials Science University of Szeged Szeged H-6720 Hungary., Honarfar A; Chemical Physics and NanoLund Lund University Box 124 Lund 22100 Sweden., Pullerits T; Chemical Physics and NanoLund Lund University Box 124 Lund 22100 Sweden., Janáky C; Department of Physical Chemistry and Materials Science University of Szeged Szeged H-6720 Hungary.; ELI-ALPS ELI-HU Non-Profit Ltd. Wolfgang Sandner utca 3 Szeged H-6728 Hungary.
Jazyk: angličtina
Zdroj: Advanced functional materials [Adv Funct Mater] 2020 Aug 03; Vol. 30 (31), pp. 2002124. Date of Electronic Publication: 2020 Jun 25.
DOI: 10.1002/adfm.202002124
Abstrakt: In this study, the photoelectrochemical behavior of electrodeposited FeNiOOH/Fe 2 O 3 /graphene nanohybrid electrodes is investigated, which has precisely controlled structure and composition. The photoelectrode assembly is designed in a bioinspired manner where each component has its own function: Fe 2 O 3 is responsible for the absorption of light, the graphene framework for proper charge carrier transport, while the FeNiOOH overlayer for facile water oxidation. The effect of each component on the photoelectrochemical behavior is studied by linear sweep photovoltammetry, incident photon-to-charge carrier conversion efficiency measurements, and long-term photoelectrolysis. 2.6 times higher photocurrents are obtained for the best-performing FeNiOOH/Fe 2 O 3 /graphene system compared to its pristine Fe 2 O 3 counterpart. Transient absorption spectroscopy measurements reveal an increased hole-lifetime in the case of the Fe 2 O 3 /graphene samples. Long-term photoelectrolysis measurements in combination with Raman spectroscopy, however, prove that the underlying nanocarbon framework is corroded by the photogenerated holes. This issue is tackled by the electrodeposition of a thin FeNiOOH overlayer, which rapidly accepts the photogenerated holes from Fe 2 O 3 , thus eliminating the pathway leading to the corrosion of graphene.
Competing Interests: The authors declare no conflict of interest.
(© 2020 The Authors. Published by WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim.)
Databáze: MEDLINE
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