Renewable Energy & Sustainability Heroes by GineersNow Engineering GineersNow Engineering Magazine Issue No. 017, Ren | Page 28

Converting Carbon Dioxide Emissions Into Fuel
It turns out that the agent lies in our sand all this time.
Scientists and engineers have been working
on the conversion of carbon dioxide
emissions to energy for a long time, finding
the perfect material to efficiently convert
sunlight, carbon dioxide and water or
hydrogen to fuel. The issue is always about
the chemical stability of carbon dioxide. But
now, scientists from the University of Toronto
(U of T) might have discovered the material to
combat that issue.
They believe that they have developed a
way to perform this conversion of emissions
to energy-rich fuel and that is through
silicon. This element is an abundant natural
resource being readily available in sand, and
the seventh most abundant element in the
universe and the second most abundant
element on the Earth’s crust.
Geoffrey Ozin, a chemistry professor in U
of T’s Faculty of Arts & Science, said that a
chemistry solution to climate change requires
a material that is a highly active and selective
catalyst to enable the conversion of carbon
dioxide to fuel. He added that it also needs to
be made of elements that are low cost, non-
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Renewable Green Leaders • May 2017
toxic and readily available. Silicon is so far
the best candidate.
As indicated in a report in the Nature
Communications, the hydride-terminated
silicon nanocrystals, or nanostructured
hydrides, have an average diameter of 3.5
nanometres and feature a surface area and
optical absorption strength sufficient to
efficiently harvest the near-infrared, visible
and ultraviolet wavelengths of light from
the sun together with a powerful chemical-
reducing agent on the surface that efficiently
and selectively converts gaseous carbon
dioxide to gaseous carbon monoxide.
This only means that soon we can produce
energy without the usual harmful emissions.
The U of T Solar Fuels Research Cluster,
where Ozin is its leader, sees the great
potential in this new discovery and works on
increasing the activity, enhancing the scale
and boosting the rate of production. The lab
now aims to have its demonstration unit and
moreover, a solar refinery.