10.1021/acs.jpcc.8b02971.s001
Pom L. Kharel
Pom L.
Kharel
Paul M. Cuillier
Paul M.
Cuillier
Kasun Fernando
Kasun
Fernando
Francis P. Zamborini
Francis P.
Zamborini
Bruce W. Alphenaar
Bruce W.
Alphenaar
Effect of Rare-Earth Metal Oxide Nanoparticles on
the Conductivity of Nanocrystalline Titanium Dioxide: An Electrical
and Electrochemical Approach
American Chemical Society
2018
trap states
undoped films
Cyclic voltammograms
charge transfer
NTD film
Doped films
samples show
nanocrystalline titanium dioxide
enhancement mechanism
electron acceptor
earth oxide
electron transport material
Nanocrystalline Titanium Dioxide
photocatalytic applications
NTD performance
Electrochemical Approach Doping
electrochemical impedance measurements
rare-earth metal oxides
light sensitivity
Rare-Earth Metal Oxide Nanoparticles
scan rate dependence
electrochemical study
rare-earth oxide-doped NTD films
trap regime
space charge density
2018-06-13 00:00:00
Journal contribution
https://acs.figshare.com/articles/journal_contribution/Effect_of_Rare-Earth_Metal_Oxide_Nanoparticles_on_the_Conductivity_of_Nanocrystalline_Titanium_Dioxide_An_Electrical_and_Electrochemical_Approach/6736607
Doping
of rare-earth metal oxides into nanocrystalline titanium
dioxide (NTD) films is known to improve performance for photovoltaic
and photocatalytic applications; however, the reasons for this improvement
are not well understood. To explore the enhancement mechanism, an
electrical and electrochemical study of rare-earth oxide-doped NTD
films was performed. Doped films were found to be 40–50 times
more conductive than undoped films, with linear current–voltage
characteristics and decreased light sensitivity. Cyclic voltammograms
of doped samples show an enhanced scan rate dependence in the deep
trap regime due to a slower charge trapping rate. Finally, electrochemical
impedance measurements reveal a decrease in space charge density and
a shift in the flat-band potential. Taken together, these results
suggest that charge transfer from the rare earth oxide neutralizes
the deep trap states in the NTD film, decreasing charge scattering,
and improving the NTD performance as an electron acceptor and electron
transport material.