Thursday, November 3, 2016 3:00 pm
-
4:00 pm
EDT (GMT -04:00)
The Waterloo Institute for Nanotechnology (WIN) presents a seminar by Professor Ayse Turak, from the Department of Engineering Physics, McMaster University – Ontario, Canada
Solution processed nanoparticles for interfacial engineering in organic photovoltaics
Abstract
The
next
generation
of
solar
cells
need
to
be
cheap,
accessible
and
flexible
for
widespread
adoption.
Solar
cells
based
on
semiconducting
organic
molecules
(organic
photovoltaics
or
OPVs)
have
already
been
recognized
as
a
key
strategic
approach
for
flexible
and
economic
solar
power
devices.
Among
all
alternative
solar
technologies,
OPVs
have
the
potential
to
be
the
most
cost-effective
for
consumers
in
the
long
term.
However,
the
success
of
OPVs
depends
on
resolving
current
technological
obstacles:
low
efficiencies,
short
lifetimes
and
high
costs.
Our
work,
focussing
on
cheap
solution-based
routes
for
nanostructuring
in
OPVs,
are
critical
to
meeting
the
10-10
performance
and
stability
targets
(10%
efficiency,
10
year
lifetime)
necessary
for
device
commercialization.
In
our
work,
we
focus
on
nanoparticle
dispersions
in
periodic,
quasi-periodic,
oriented,
and
randomly
distributed
networks
at
electrode
interfaces
with
organic
semiconductors.
Incorporation
of
interlayers
at
the
electrode
surface
is
a
key
design
strategy
for
improving
device
efficiency,
light
management,
and
operational
stability.
Typically
interlayers
are
deposited
by
vacuum
thermal
evaporation,
adding
complexity
and
cost
to
device
manufacture.
Systematically
controlling
the
dispersion
during
evaporation
is
extremely
challenging.
Our
approach
is
to
use
solution
chemistry
methods
to
deposit
and
control
the
dispersion
of
our
interlayers,
using
a
simple
technique
for
assembling
a
2D
array
of
nanoparticles:
reverse
micelle
deposition.
Using
this
approach,
we
have
been
studying
a
variety
of
oxide
and
dielectric
nanoparticles
to
understand
the
nature
of
interfaces
in
such
devices.
By
varying
the
chemistry,
morphology,
refractive
indicies,
and
work
functions
of
our
nanoparticle
arrays,
we
aim
to
shed
light
on
the
coupling
of
electronic
and
optical
enhancements
in
device
structures,
to
decouple
the
effects
of
interfacial
reactions
from
those
from
non-homogeneous
electric
field
distributions
on
device
degradation,
and
to
uncover
the
complicated
effects
of
optimized
submonolayer
coverage.