The Role of Surface States in the Oxygen Evolution Reaction on Hematite
Artikel i vetenskaplig tidskrift, 2014

Hematite (alpha-Fe2O3) is an extensively investigated semiconductor for photoelectrochemical (PEC) water splitting. The nature and role of surface states on the oxygen evolution reaction (OER) remain however elusive. First-principles calculations were used to investigate surface states on hematite under photoelectrochemical conditions. The density of states for two relevant hematite terminations was calculated, and in both cases the presence and the role of surface states was rationalized. Calculations also predicted a Nerstian dependence on the OER onset potential on pH, which was to a very good extent confirmed by PEC measurements on hematite model photoanodes. Impedance spectroscopy characterization confirmed that the OER takes place via the same surface states irrespective of pH. These results provide a framework for a deeper understanding of the OER when it takes place via surface states.

water splitting

energy conversion

hematite

surface states

photoelectrochemistry

Författare

Beniamino Iandolo

Chalmers, Teknisk fysik, Kemisk fysik

Anders Hellman

Chalmers, Teknisk fysik, Kemisk fysik

Angewandte Chemie - International Edition

1433-7851 (ISSN) 1521-3773 (eISSN)

Vol. 53 13404-13408

Styrkeområden

Nanovetenskap och nanoteknik

Transport

Energi

Materialvetenskap

Infrastruktur

C3SE (Chalmers Centre for Computational Science and Engineering)

Ämneskategorier

Atom- och molekylfysik och optik

DOI

10.1002/anie.201406800