Engineering Transparent Conducting Materials for High-Efficiency
Photoelectrochemical Cells
Alberto Vomiero
Chair in Experimental Physics
Division of Materials Science,
Department of Engineering Science and Mathematics
Luleå University of Technology, Luleå, Sweden
The typical photoanode in several photoelectrochemical systems including dye- and quantum
dot- sensitized solar cells and photoelectrochemical cells for water splitting is composed of a
wide band gap semiconductor, which acts as electron transporter. Anatase TiO
2
nanoparticles
are one of the most used oxides and are able to deliver the highest photoconversion efficiency
in this kind of solar cells, but intense research in the last years was also addressed to ZnO and
other composite systems. [1] Modulation of the composition and shape of nanostructured
photoanodes is key element to tailor the physical chemical processes regulating charge
dynamics and, ultimately, to boost the efficiency of the end user device, by favoring charge
transport and collection, while reducing charge recombination.
We investigated several systems: (i) TiO
2
nanoparticles / ZnO nanowires; (ii) Multiwall
carbon nanotubes (MWCNTs) / TiO
2
nanoparticles; (iii) TiO
2
nanotubes; (iv) Hierarchically
self-assembled ZnO sub-microstructures. Both dye molecules and semiconducting quantum
dots were applied as light harvesters. Exciton generation and separation plays critical role in
these systems. For this reason, we investigated exciton dynamics in different semiconducting
nanocrystals couple with suitable transparent conducting oxides. [2-4]
Possible tailoring of structure and morphology of the photoanodes and of the quantum dots,
and their implication in improving the functional properties of these kinds of solar cells will
be discussed in detail.
References
[1] I. Concina and A. Vomiero,
Small
,
2015,
11
, 1744-1774.
[2] I Concina et al.
J. Phys. Chem. Lett.
,
2015,
6
, 2489−2495.
[3] H. Zhao et al.
Nanoscale
2016
,
8
, 4217-4226.\
[4] L. Jin et al.
Advanced Science
,
2016
,
3
, 1500345
I 14
-96-
