Adsorbed water induced electrical conduction properties of

Adsorbed water induced electrical conduction properties of hexagonal and monoclinic CePO4
Pusztai Péter1, Haspel Henrik1, Kukovecz Ákos1,2, Kónya Zoltán1,3
1 University of Szeged, Department of Applied and Environmental Chemistry, Szeged
2 MTA-SZTE "Lendület" Porous Nanocomposites Research Group, Szeged
3 MTA-SZTE Reaction Kinetics and Surface Chemistry Research Group, Szeged
The industrial and medical importance of lanthanide- and cerium-phosphate nanomaterials
has become undisputedly significant. Due to their unique electronic configuration and low
toxicity these nanomaterials can be utilized in optoelectronic devices and biomedical labeling.
The available open literature mostly focuses on the improvement of photoluminescent
properties of cerium-phosphate nanomaterials however their electronic conduction behavior
under humid condition has seldom investigated yet.
In this study we prepared hexagonal and monoclinic cerium-phosphate nanowires via two
different methods. The morphology and crystallinity of the nanowires were investigated by
transmission electron microscopy and X-ray diffractometry. Energy dispersive X-ray
spectroscopy was applied to examine the purity and elemental composition of the samples.
Nitrogen-adsorption and water-adsorption measurements were carried out to investigate the
differences in the samples’ specific surface area and their water adsorption capacity under
different relative humidity conditions.
For the electrical conduction study the nanowires were drop-casted onto alumina
supported micropatterned platinum integrated electrodes and placed into sealed vessels
containing different saturated salt solutions to ensure various relative humidity conditions.
The conduction properties of the nanowires were investigated by impedance spectroscopic
and potential step methods as a function of changing relative humidity.
The financial support of the TÁMOP-4.2.2.A-11/1/KONV-2012-0047, TÁMOP
4.2.4.A/2-11-1-2012-0001 and OTKA NN 110676 projects is acknowledged.