TU Darmstadt / ULB / TUprints

Pinning of the Fermi Level in CuFeO₂ by Polaron Formation Limiting the Photovoltage for Photochemical Water Splitting

Hermans, Yannick ; Klein, Andreas ; Sarker, Hori Pada ; Huda, Mohammad N. ; Junge, Henrik ; Toupance, Thierry ; Jaegermann, Wolfram (2021)
Pinning of the Fermi Level in CuFeO₂ by Polaron Formation Limiting the Photovoltage for Photochemical Water Splitting.
In: Advanced Functional Materials, 2020, 30 (10)
doi: 10.26083/tuprints-00019358
Article, Secondary publication, Publisher's Version

[img]
Preview
Text
adfm.201910432.pdf
Copyright Information: CC BY-NC-ND 4.0 International - Creative Commons, Attribution NonCommercial, NoDerivs.

Download (3MB) | Preview
Item Type: Article
Type of entry: Secondary publication
Title: Pinning of the Fermi Level in CuFeO₂ by Polaron Formation Limiting the Photovoltage for Photochemical Water Splitting
Language: English
Date: 2021
Place of Publication: Darmstadt
Year of primary publication: 2020
Publisher: Wiley
Journal or Publication Title: Advanced Functional Materials
Volume of the journal: 30
Issue Number: 10
Collation: 10 Seiten
DOI: 10.26083/tuprints-00019358
Corresponding Links:
Origin: Secondary publication service
Abstract:

CuFeO₂ is recognized as a potential photocathode for photo(electro)chemical water splitting. However, photocurrents with CuFeO₂-based systems are rather low so far. In order to optimize charge carrier separation and water reduction kinetics, defined CuFeO₂/Pt, CuFeO₂/Ag, and CuFeO₂/NiOx(OH)y heterostructures are made in this work through a photodeposition procedure based on a 2H CuFeO₂ hexagonal nanoplatelet shaped powder. However, water splitting performance tests in a closed batch photoreactor show that these heterostructured powders exhibit limited water reduction efficiencies. To test whether Fermi level pinning intrinsically limits the water reduction capacity of CuFeO₂, the Fermi level tunability in CuFeO₂ is evaluated by creating CuFeO₂/ITO and CuFeO₂/H₂O interfaces and analyzing the electronic and chemical properties of the interfaces through photoelectron spectroscopy. The results indicate that Fermi level pinning at the Fe³⁺/Fe²⁺ electron polaron formation level may intrinsically prohibit CuFeO₂ from acquiring enough photovoltage to reach the water reduction potential. This result is complemented with density functional theory calculations as well.

Status: Publisher's Version
URN: urn:nbn:de:tuda-tuprints-193588
Classification DDC: 500 Science and mathematics > 540 Chemistry
600 Technology, medicine, applied sciences > 620 Engineering and machine engineering
Divisions: 11 Department of Materials and Earth Sciences > Material Science > Electronic Structure of Materials (ESM)
11 Department of Materials and Earth Sciences > Material Science > Surface Science
Date Deposited: 26 Aug 2021 12:27
Last Modified: 21 Nov 2022 07:20
URI: https://tuprints.ulb.tu-darmstadt.de/id/eprint/19358
PPN: 495587540
Export:
Actions (login required)
View Item View Item