- Next up will be Linda Nhon, from just
Chemistry and Biochemistry, speaking on
artificial photosynthesis,
From Sunlight to Fuel.
- In 20 years time, the
average global temperature
is expected to increase
by one degree Celsius,
which will cause damaging climate stress,
altering our environmental, economical
and political landscape.
This increase in temperature is caused
by carbon dioxide emissions
into the atmosphere.
Currently, one of the
major contributing factors
of CO2 emissions comes from
the transportation sector,
which still depends
heavily on the combustion
of fossil fuels to generate the gasoline
that auto cars currently run on.
Now, what if I told you that my technology
will allow you to
continue driving your car
that depends on this gasoline,
but not emit CO2 into the atmosphere?
In fact, you'll be
recycling the carbon dioxide
back into the car to
generate this liquid fuel.
Currently, I'm working on a device
that captures carbon
dioxide and reduces it
to hydrocarbons, no excess liquid fuel.
Now, for this chemical
reaction to proceed,
an external energy source is required.
Fortunately, this source is both infinite
and environmentally benign: sunlight.
Inspired by photosynthesis, I've made
a set of light-absorbent materials
to harvest the solar energy.
When these dyes absorb
the photons from the sun,
they undergo a process
known as photoexcitation.
Now, during photoexcitation,
the dye produces
an exoton, which is a
bound positive and negative
charge, kind of like two
magnets stuck together.
It's important to keep the negative charge
away from the positive, because
this negative charge is needed to activate
this catalyst that will reduce
the carbon dioxide to the hydrocarbon.
Our experiments have
shown that we can control
the directional flow of our charges,
via the careful design of our dyes.
Statistical analysis has
also shown that if our
device performs at a 12%
conversion efficiency,
with the sun deployed to just 2%
of the Earth's surface
for eight hours a day,
we will provide enough
fuel for all the vehicles
on this planet for an entire month.
In summary, my technology will alter
the energy landscape, because
it eliminates CO2 emissions,
reduces economic challenges by maintaining
our current infrastructure, and introduces
a green alternative energy source.
To close, by attacking
one of the 21st century's
greatest climate challenges,
my research will make
an incredible impact on our
energy sustainable future.
Thank you.
(applause)
