Could carbon dioxide be the solution to climate change?

In the drama of climate change, carbon dioxide has long played the role of arch-villain.

Now, though, Canada Research Chair of Materials Chemistry and Nanochemistry and University Professor of Chemistry Geoffrey Ozin wants to recast the infamous greenhouse-gas scoundrel in the role of hero, placing it centre stage in the development of carbon-neutral, renewable energy.  

And thanks to an investment of $1 million from the Connaught Global Challenge Award program, he is setting out to do just that.

“The public has heard of carbon capture and storage,” Ozin says. “They haven’t heard about carbon capture and utilization.”

Carbon dioxide, it turns out, plays many roles other than heating the planet. It’s used to manufacture industrial chemicals and polymers. It’s a component in urea, a key part of many fertilizers.  

And, it can be used to make methane and diesel fuels. 

“Carbon dioxide already forms the basis of a megaton industry for making chemicals, materials, cement and fertilizers,” says Ozin. “Why not use it as much as you can? You could build a global economy on a resource that’s all around us. And if you happen to use Gigatons every year, then you could keep atmospheric carbon dioxide levels at sustainable levels indefinitely.”

Ozin (pictured at right) is leading a multidisciplinary team, dubbed “The U of T Solar Fuels Cluster” on a quest to develop a process for converting carbon dioxide into an energy-rich renewable fuel, using a carbon-neutral cycle.  

Ozin’s approach fits the nature of the Global Challenge Award perfectly. The award was created in 2011 to bring together the university’s leading researchers from multiple disciplines with innovators from other sectors to enhance U of T’s contributions to issues facing global society. Proposals come from the U of T research community, involving large interdisciplinary teams and are subjected to the highest level of international peer review.   

The Connaught Fund is currently valued at more than $105 million. It was founded in 1972 from the sale of the Connaught Laboratories for $29 million. The labs had produced vaccines and, notably, insulin after it was discovered by U of T researchers Frederick Banting and Charles Best in 1921. The Connaught fund has since awarded more than $135 million to U of T scholars.  

“The Connaught Fund has always been focused on enabling research relevant to society,” says Professor Vivek Goel, U of T’s vice-president, research and innovation. “The goal of the Global Challenge Award provides a level of funding that helps our researchers go very deeply into a problem that affects everyone on the planet and create progress on solutions to that problem. 

“These challenges demand experts from a wide range of areas coming together – no sole scholar can do it alone. The focus of the Ozin team on renewable energy will addressone of the great problems of our time. The Connaught Committee believes the wide range of expertise on Geoff’s team can deliver important advances on this vital topic.”

Ozin is joined in the project by

• Charles Mims, chemical engineering and applied chemistry (CEAC)
• Nazir Kherani, materials science and engineering (MSE) and electrical and computer engineering (MSE)
• Douglas Perovic, MSE
• Cathy Chin, CEAC
• Ben Hatton, MSE
• Chandra Veer Singh, MSE
• Zhenghong Lu, MSE

Ozin says people tend to view carbon dioxide as a waste product because it’s what’s left over after burning fuel or breathing air. It’s a very stable molecule, which doesn’t react easily with other materials. But given the right catalyst, it can be broken up and transformed into carbon monoxide, methane, methanol, ethylene, formic acid and other highly useful chemicals. 

Finding the right catalyst involves more than identifying substances that can coax reactions out of CO2. Ozin researches how to shape materials on a nanoscopic scale, creating structures a few billionths of a metre in size. Nanostructuring can do things like maximize the surface area where gas and catalyst interact. More surface area means more chemical reaction. 

“A carbon dioxide economy will depend on nanostructured forms of semiconductors and metals,” Ozin says. “We foresee a sunlight-assisted conversion of gaseous CO2 to fuel, using catalysis to create a ‘solar refinery’ that is, critically, predicated on existing industrial infrastructure and combustion processes.”

Ozin first turned his attention to this problem seven years ago when he was 65 years old. He says it sometimes feels odd to be working on something so tied to immediately pressing global challenges, where mere discovery is only a part of the recipe on a long road to success. 

“I’m an academic used to doing basic science,” he says. “But for global industry, you have to create materials that are not just different from what already exists, but that do a particular job better. You have to boil things down to simpler, scalable components that are abundant, low-cost, and stable under every imaginable condition – in varying sunlight levels, at different temperatures, and under reaction.” 

Despite the challenges, he remains convinced that science and engineering can reform CO2 into a productive part of global society.

“I believe that carbon dioxide should be viewed as more than a combustion waste product of fossil fuel,” he says. “We should think of it as a chemical resource to be harvested and recycled into renewable fuel.”

His mantra is “solar fuels from the sun not fossil fuels from the earth”. 

The support from the Connaught Fund runs from September 2015 to December 2017. 

The Connaught Committee also made a $170,000 Global Challenge Award to a second interdisciplinary team led by Professor Amr Helmy of electrical and computer engineering for his project entitled The Quantum Internet: Charting the Critical Path.  U of T News will post a feature on this project soon.  

(See the original image of Australia's carbon emissions from Carbon Visuals on Flickr)