It is a question that researchers everywhere are grappling with: how can we meet an increasing global demand for energy鈥攆ueled in part by developing countries experiencing dramatic population and economic growth鈥攁nd how can we do it in ways that eliminate dangerous carbon emissions? For 黑料吃瓜网researchers like Dr. Mita Dasog, one way is as clear as day: solar energy.
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鈥淪olar is a great renewable resource,鈥� says Dr. Dasog, associate professor and Izaak Walton Killam Memorial Research Chair at the Department of Chemistry. 鈥淚t is freely available to us, and it is very abundant. In fact, we receive an entire year鈥檚 worth of energy on the earth鈥檚 surface in the form of sunlight in just 80 minutes.鈥�
Dr. Mita Daog in the lab (Daniel Abriel, photo).
But sunlight is not always available, which means we need ways to store its energy so that we can access it on cloudy days or at night. Moreover, the technologies we use to collect, convert, store, and distribute that energy are not affordable enough to be available to everyone everywhere at any time. Thanks to the work of Dal researchers like Dr. Dasog and the university鈥檚 Clean Technologies Research Institute, that could soon change.
Since its launch in 2017, the institute has dedicated itself to developing technologies that reduce the world鈥檚 reliance on non-renewable resources, limit waste production, and address the negative environmental impacts of our daily activities. These efforts include harnessing the full potential of solar energy. Through the development of innovative new technologies that transform sunlight into fuel, revolutionize solar cells, and make battery storage more feasible, the institute鈥檚 researchers are making solar energy accessible, reliable, and affordable. And their ideas are helping to create a world powered by clean energy.
No hard cell
One such idea is being explored by Dr. Ghada Koleilat, associate professor at the departments of Process Engineering & Applied Science and Electrical & Computer Engineering. Instead of rigid, bulky solar panels that are expensive to install, her lab is developing a hybrid organic-inorganic solar cell technology that can be applied like a paint or a film to any surface.
鈥淥ur technology uses materials that are low cost and can be mixed and made into a solution that is ready to be used within one hour,鈥� explains Dr. Koleilat. 鈥淲e can then apply that solution to a large surface area or a flexible substrate that can be rolled out without the expense and limitations of traditional solar cells.鈥�
Dr. Koleilat is using nanomaterials鈥攎aterials so small they can only be viewed with special equipment鈥攖o develop her solar cells. The goal is to engineer a solution that is as long-lasting and efficient in converting solar energy into electrical energy as solar panels. That means researching different raw materials, but the one that most interests her is perovskite. Studies have found that solar cells made from these earth-abundant minerals are comparable to traditional solar panels for efficiency. But there are issues related to the longevity and lead content of perovskite, both of which 鈥―r. Koleilat is working to address.
If Dr. Koleilat is successful, her efforts will enable adoption of solar energy to an extent previously unimaginable. More than benefiting Canadian households and businesses, the ability to paint solar cells onto any surface creates opportunities to make electricity available in places where costs and lack of infrastructure pose significant obstacles. That, Dr. Koleilat says, will change the world.
鈥淚n developing nations and regions that are in conflict, there is an urgent need for energy generation that is mobile, low cost, and versatile,鈥� she explains. 鈥淭his is one way to target that need. This technology could bring energy to a refugee camp, provide lamplight so a child can read at night, or make it possible to boil water. It doesn鈥檛 take much power to make lives in these areas better, so my main hope is to meet that need for energy.鈥�
Dr. Ghada Koleilat wants to harness the power of the sun using nanomaterials (Daniel Abriel, photo).听
Financial support for research like Dr. Koleilat鈥檚 could make such hopes a reality within five to 10 years. But she cautions that her work is just one of many puzzle pieces that must come together to bring the world clean energy. 鈥淣o technology is the one technology,鈥� she notes. 鈥淚t will take several complementary technologies in an integrated system that takes advantage of all the renewable resources that we have. That is what we are doing at Dalhousie, and there is real beauty in that multipronged approach for me.鈥�
Fueling the future
As Dr. Koleilat transforms solar cell technology into more practical applications, Dr. Dasog is exploring another kind of transformation: how best to turn solar energy into a fuel, specifically hydrogen, so it鈥檚 accessible when the sun is not.
鈥淗ydrogen allows you to store solar energy for a very long time, so it is available whenever you need it,鈥� Dr. Dasog explains. 鈥淗ydrogen has a high gravimetric energy density, which means it can store large amounts of energy per given mass. That makes it great for uses such as operating large transportation vehicles like ships, trains, or airplanes, and it will play an important role in meeting our need for cleaner energy.鈥�
Although hydrogen itself is a relatively clean-burning fuel, it has long been produced using fossil fuels or precious metals. Neither process is sustainable nor cost efficient, but Dr. Dasog believes she has a solution. Drawing inspiration from photosynthesis鈥攖he process through which plants transform solar energy into food鈥擠r. Dasog is developing a material that can absorb sunlight and use that energy to make hydrogen from water, thus creating a clean fuel. Her approach uses silicon as a photocatalyst, a non-toxic element that is the second most abundant on earth.
Since silicon is already being made and used for other green energy applications, Dr. Dasog is optimistic about the potential impact of her work. Large-scale hydrogen generation pilot projects are currently underway in countries such as Germany, India, Japan, and South Korea, all of which are using different catalysts. Dr. Dasog believes that silicon-based catalysts can be used in similar setups. But the big question is whether the efficiency she has achieved in her lab will be matched in the real world.
鈥淚f our efforts are successful, then we can make affordable green hydrogen,鈥� Dr. Dasog says. 鈥淭hat will not only go a long way toward addressing climate change, but also create economic opportunities for Canada because we can ship that hydrogen to other countries.鈥�
While Dr. Dasog鈥檚 project has significant economic potential, it鈥檚 the ability of her research to fundamentally change how we meet the world鈥檚 growing energy needs that fires her passion. It would facilitate the shift away from fossil fuels, which not only brings the promise of clean energy, but also would end the dominance of oil-rich countries in meeting international energy needs.
鈥淭here is some source of silicon available globally, which means we shouldn鈥檛 run into the supply issues we have seen recently where one country has the monopoly over an energy resource,鈥� she says. 鈥淏y continuing to bring the cost of green hydrogen down and improving the ability to scale up, we can take advantage of solar energy to address the challenges of climate change and energy storage and meet clean energy requirements.鈥�
A better battery
Although hydrogen offers the benefit of anytime, anywhere access to solar energy, batteries remain the best storage option for meeting the needs of our power grids and households. This is where Dr. Ian Hill hopes to make a difference. He is working on a more affordable, longer-lasting battery to charge the solar energy revolution.
Dr. Hill鈥檚 research is focused on optimizing redox flow battery technology for solar energy conversion and storage. A battery is connected to two tanks of a solution that enables an electrical charge to flow between the battery鈥檚 electrodes for charging and generating energy. The energy created through that exchange is either available for immediate use or stored for later use.
鈥淲hen the sun shines, it charges the battery,鈥� says Dr. Hill, the chair and George Munro professor at the Department of Physics and Atmospheric Science. 鈥淲hen the sun鈥檚 not shining, you use the battery to power things in your home. One advantage of this technology is that it is very affordable to scale up for larger uses if the solution in the tanks is inexpensive to produce.鈥�
Dr. Hill has been collaborating with chemists to test different low-cost organic solutions. But there is a more pressing concern on his mind: how to stop the gradual loss of energy in storage, charging, and releasing that contributes to short battery life.
鈥淚n my lab, we are charging and discharging redox flow batteries thousands of times to identify the factors which cause that loss,鈥� he says. 鈥淚f we can do that, we can determine why that loss is happening and how we can stop it. That would make the batteries last longer, and the longer we can make them last, the less expensive they will be.鈥�
Charging a new generation
It鈥檚 challenges like making a longer lasting battery that prompted Dr. Hill鈥檚 increased interest in redox flow batteries. His research has resulted in vital insights that not only have the potential to enhance battery longevity, but also have cemented Dal鈥檚 position as a leading centre for energy storage research. Dr. Hill鈥檚 determination to push the limits of this technology is informed as much by a desire to make a difference as it is by the opportunity to collaborate with a new generation that is eager to advance clean energy adoption.
鈥淥ccasionally, there is a great new discovery that really pushes the field forward. But more often it takes a lot of people working together for a very long time to make incremental improvements to the technology,鈥� he says. 鈥淢y goal is to help students realize that this is hard work. If it weren鈥檛, people would have solved this problem years ago.鈥�
One student who is stepping up to take on that hard work is Jay Deshmukh (BEng鈥�21). A Master of Applied Science candidate working at the Jeff Dahn-Michael Metzger-Chongyin Yang lab and co-supervised by Michael Freund. Deshmukh is also developing better battery technology to make widespread adoption of solar and wind energies possible. Using sodium-ion batteries as his medium, he is exploring the benefits of electrodes made from Prussian white analogues鈥攃ompounds that can be made using low-cost materials such as iron, manganese and sodium.
鈥淭hese are elements we are never going to run out of, so they are very plentiful for scaling up,鈥� Deshmukh says. 鈥淔ew people have used similar chemistries before and reported promising performance. But the sad part is that it is not as energy dense as lithium-ion and the longevity is not as good as we would like. By tweaking various parameters, we hope to address both of those issues.鈥�
Master of Applied Science candidate Jay Deshmukh (both pages) in the lab (Daniel Abriel, photo).
Deshmukh believes this will be doable at Dalhousie. He鈥檚 impressed by the breadth and depth of clean technology research being conducted here, and by the many experts he can engage to help him realize his vision. 鈥淚 saw that there were so many amazing initiatives going on here and realized I could either keep an eye on it or be part of it,鈥� he says. 鈥淭here is unique expertise in all aspects of renewable energy, whether that is batteries or solar technologies. There is also an excellent partnership with Tesla for battery research that has been beneficial for giving us insights into industry expectations that we can use to tailor our research accordingly.鈥�
A ray of hope
Solar cells that can be applied like paint. Hydrogen fuel that harnesses solar energy. Long-lasting, affordable batteries. These are just a few of the technologies 黑料吃瓜网researchers are developing to bring clean energy to everyone, everywhere. In doing so, they are also fostering the next generation of clean technology leaders, who will continue to drive progress on one of our most urgent challenges.
鈥淲e need to eventually eliminate our dependence on fossil fuels,鈥� says Dr. Ian Hill. 鈥淚f we are going to do that, we need solar energy. It鈥檚 certainly the one we would like to use the most because it鈥檚 the most beneficial and probably has the fewest negative side effects. I firmly believe we are going to get there as a society and that 黑料吃瓜网is going to play a major role in making that happen.
This story appeared in the DAL Magazine Spring/Summer 2023 issue. Flip through the rest of the issue using the links below.