Hi,
The CORE-CM seminar this week is:**
*
March 21: Juan Bisquert *
/Department of Physics, University Jaume I, Castello Spain /
"Solar energy conversion with nanoheterostructures"
The abstract is below
BPS 1400 at 12:00pm,
Pizza and cookies available at 11:45am
Phil Duxbury
Full seminar list is at:
http://www.pa.msu.edu/cmp/CORE-CM/SeminarSpring2013.html
*
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Abstract
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Nanostructures based on inorganic semiconductor layers, molecular
catalysts and colloidal quantum dots, are very promising candidates to
achieve efficient solar cells and photoelectrochemical cells for the
production of solar fuels. Empirical progress has been realized but
fundamental methods of analysis are required to relate electronic
operation to composition and structure. Here we discuss fundamental
processes that induce the directionality of photogenerated electron and
hole carriers towards a productive result, either electrical power or
chemical fuel. We address specific mechanisms and electronic processes
of dye-sensitized solar cells, organic solar cells, quantum dot solar
cells, and visible light absorber semiconductor heterostructures for
solar water splitting. Recent analysis based on Impedance Spectroscopy
(IS) results allows to derive a simple model that works well in many
cases. The model *c*onsists on a combination of recombination resistance
and chemical capacitance, and it provides the separation of energetic
and kinetic components of the solar cells operation. I discuss the
relation between recombination resistance and capacitance of the cell
measured by IS, with the j-V curve both in the dark and under (1 sun)
illumination. We can provide a detailed energetic map that shows the
limitation to injection (photocurrent) and split of Fermi levels
(photovoltage) by recombination. We also discuss the application of
impedance spectroscopy experimental and theoretical tools to identify
the mechanism of operation of photoanodes for solar fuel production.
