Assessing the Suitability of Iron Tungstate (Fe<sub>2</sub>WO<sub>6</sub>) as a Photoelectrode Material for Water Oxidation
Fatwa F. Abdi
Abdelkrim Chemseddine
Sean P. Berglund
Roel van de Krol
10.1021/acs.jpcc.6b10695.s001
https://acs.figshare.com/articles/journal_contribution/Assessing_the_Suitability_of_Iron_Tungstate_Fe_sub_2_sub_WO_sub_6_sub_as_a_Photoelectrode_Material_for_Water_Oxidation/4498469
Orthorhombic
iron tungstate (Fe<sub>2</sub>WO<sub>6</sub>), with
a reported bandgap of ∼1.5–1.7 eV, is a potentially
attractive material as the top absorber in a tandem photoelectrochemical
(PEC) device. Few studies have been carried out on this material,
and most of the important optical, electronic, and PEC properties
are not yet known. We fabricated thin film Fe<sub>2</sub>WO<sub>6</sub> photoanodes by spray pyrolysis and identified the performance limitations
for PEC water oxidation. Poor charge separation is found to severely
limit the photocurrent, which is caused by a large mismatch between
the light penetration depth (∼300 nm) and carrier diffusion
length (<10 nm) of the material. In addition, the conduction band
of Fe<sub>2</sub>WO<sub>6</sub> lies 0.65 V positive of the reversible
hydrogen electrode potential, which means that a large external bias
potential is required for water oxidation. On the basis of these observations,
we critically discuss the suitability of Fe<sub>2</sub>WO<sub>6</sub> as a novel photoelectrode material for photoelectrochemical and
photocatalytic applications.
2016-12-15 00:00:00
Water Oxidation Orthorhombic iron tungstate
spray pyrolysis
water oxidation
conduction band
novel photoelectrode material
Poor charge separation
tandem photoelectrochemical
PEC properties
hydrogen electrode
photocatalytic applications
PEC water oxidation
Iron Tungstate
film Fe 2 WO 6 photoanodes
0.65 V
Few studies
nm
Photoelectrode Material
Fe 2 WO 6
performance limitations