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May 20-21, 2019 | Vienna, Austria
Biomaterials and Nanomaterials &
Materials Physics and Materials Science
2
nd
International Conference on
Journal of Materials Science and Nanotechnology | Volume 3
Core-shell SrTaO
2
N nanowire photoanode for photoelectrochemical water oxidation
Adam Slabon
Tockholm University, Sweden
S
olar fuel generation in the form of hydrogen derived
directly from water represents an environment-friendly
technology to obtain clean energy. Oxynitrides are promising
candidates for photoanodes in water-splitting cells due to
their tunable bandgaps and low cost. Especially quaternary
oxynitrides exhibit small band gap values, between 1.8 and
2.3 eV, suggesting their potential for high solar-to-hydrogen
efficiencies.
Light absorbers in a strongly anisotropic morphology, e.g.
nanowires, enable to decouple the long axis responsible for
high light harvesting from the orthogonal axis responsible
for charge transport. This results in efficient light harvesting
while simultaneously ensuring improved charge-carrier
conductivity. Most nitrides and oxynitrides are usually
obtained in the form of microcrystals by nitridation of a
precursor oxide phase. Although Ta
3
N
5
nanowires can be
synthesized by nitridation of Ta2O5 nanowires, this method
cannot be applied to quaternary oxynitrides.
The perovskite-related oxynitride SrTaO
2
N is a prospective
photoanode candidatewith favourable band-edge positions.
We have synthesized SrTaO
2
N nanowires by hydrothermal
synthesis on a tantalum substrate and nitridation under
flowing ammonia and hydrogen. This is the first trial of a
SrTaO
2
N photoanode based on nanowires.
e
:
adam.slabon@mmk.su.se