Researchers at the University of Central Florida have developed new ways to generate energy and materials using methane, a harmful greenhouse gas.
Pound-for-pound, the comparative impact of methane on the Earth’s atmosphere is 28 times greater than carbon dioxide — another major greenhouse gas — over a 100-year period, according to the U.S. Environmental Protection Agency.
It is because methane, which has a shorter life in the air than carbon dioxide does, is more effective at trapping radiations.
The major sources of methane are energy and industry.
UCF’s new innovations allow methane to used as a green energy source and for the creation of high-performance materials that can be used to make smart devices, biotechnology and solar cells.
These inventions are the result of a collaboration between UCF’s nanotechnologist Laurene Têtard and Richard Blair, a catalysis expert. Both have worked together in research for over 10 years.
Tetard is an associate professor and associate chair of UCF’s Department of Physics and a researcher with the NanoScience Technology Center, and Blair is a research professor at UCF’s Florida Space Institute.
The Cleaner, Better Way to Produce Hydrogen
First, a method is developed to produce hydrogen without releasing carbon dioxide from hydrocarbons like methane.
By using visible light — such as a laser, lamp or solar source — and defect-engineered boron-rich photocatalysts, the innovation highlights a new functionality of nanoscale materials for visible light-assisted capture and the conversion of hydrocarbons like methane. The term defect engineering is used to describe the creation of irregularly-structured materials.
The UCF invention is able to produce hydrogen free of contaminants such as carbon dioxide, higher polyaromatics, or carbon monoxide that are commonly found in reactions carried out at higher temperatures using conventional catalysts.
This new technology could lower the price of catalysts for energy creation, increase photocatalytic efficiency in the visible range and allow more solar energy to be used for catalysis.
Solar farms, for example, could produce large quantities of hydrogen and convert methane.
“That invention is actually a twofer,” Blair says. “You get green hydrogen, and you remove — not really sequester — methane. You’re processing methane into just hydrogen and pure carbon that can be used for things like batteries.”
He said the traditional method of hydrogen production is to heat water and methane at high temperatures. However, this process also produces carbon dioxide.
“Our process takes a greenhouse gas, methane and converts it into something that’s not a greenhouse gas and two things that are valuable products, hydrogen and carbon,” Blair says. “And we’ve removed methane from the cycle.”
He noted that at UCF’s Exolith Lab they were able to generate hydrogen from methane gas using sunlight by putting the system on a large solar concentrator.
Knowing this, he says countries that don’t have abundant sources of power could use the invention since all they would need is methane and sunlight.
Methane is also found in landfills, agricultural and industrial areas, and at wastewater treatment sites.
Growing Contaminant Free Carbon Nano/Microstructures
Tetard’s and Blair’s technology allows the production of carbon structures at controlled sizes, both on the nanoscale and microscale. The photocatalyst is engineered with defects to produce well-defined, patterned nanoscale and microscopic structures. Examples include methanes, ethanes, propanes, propenes, and carbon dioxide.
“It’s like having a carbon 3D printer instead of a polymer 3D printer,” Tetard says. “If we have a tool like this, then maybe there are even some carbon scaffolding designs we can come up with that are impossible today.”
Blair said that the dream was to produce high-performance carbon material from methane. However, this is not being done at all.
“So, this invention would be a way to make such materials from methane in a sustainable manner on a large industrial scale,” Blair says.
Carbon structures can be produced in small sizes, yet they are very well constructed. They also come with a variety of patterns and sizes.
“Now you’re talking high-dollar applications, perhaps for medical devices or new chemical sensors,” Blair says. “This becomes a platform for developing all sorts of products. The application is only limited by the imagination.”
As the growth can be controlled at different wavelengths by using various lasers and solar illumination, there are many design options.
Tetard’s lab, which works at the nanoscale, is now trying to reduce the size.
“We’re trying to think of a way to learn from the process and see how we could make it work at even the smaller scales — control the light in a tiny volume,” she says.
“Right now, the size of the structures is microscale because the light focal volume we create is microsize,” she says. “So, if we can control the light in a tiny volume, maybe we can grow nano-sized objects for patterned nanostructures a thousand times smaller. That’s something we’re thinking of implementing in the future. And then, if that becomes possible, there are many things we can do with that.”
The Cleaner, Better Technology to Produce Carbon
The researchers’ better, cleaner technology for producing hydrogen was actually inspired by an earlier innovative method of theirs that makes carbon from defect-engineered boron-nitride using visible light.
The researchers discovered a way to produce hydrogen and carbon through the chemical cracking process of hydrocarbons using visible light coupled with defect-engineered boron nitride, a catalyst that is free from metals.
Compared to other methods, it’s better because it doesn’t require significant energy, time, or special reagents or precursors that leave impurities.
All that’s left is carbon and some traces of boron and nitrogen, none of which are toxic to humans or the environment.
The photochemical technology is applicable to many fields, such as sensors, new components for nanoelectronics or quantum devices, energy storage and green hydrogen production.
Strong Collaboration
As longtime research collaborators Tetard and Blair are all too familiar with the old saying, “If at first you don’t succeed, try, try again.”
“It took a while to get some really exciting results,” Tetard says. “In the beginning, a lot of the characterization that we tried to do was not working the way we wanted. We sat down to discuss puzzling observations so many times.”
They persisted, and it paid off in the form of their new inventions.
“Richard has a million different ideas on how to fix problems,” Tetard says. “So eventually, we would find something that works.”
She and Blair joined forces shortly after meeting in 2013 at UCF’s physics department. Blair had just discovered catalytic properties in the chemical compound boron nitride that were “unheard of” and wanted to publish the information and do more research.
He had a collaborator for theoretical modeling, Talat Rahman, a distinguished Pegasus Professor in the Department of Physics, but he needed someone to help characterize the findings.
“At the characterization level, that’s not where my strength is,” he says. “I have strengths that complement Laurene’s strengths. It made sense to see if we could do something together and if she could add some insight to what we were seeing.”
They hoped that, with Rahman’s collaboration and funding from the U.S. National Science Foundation (NSF), they could gain a molecular insight into the catalytic properties of boron nitride hexagonal crystal structure, a catalyst free of metal.
Typical catalysts often consist of metals, and boron nitride, sometimes called “white graphite,” has had many industrial uses due to its slippery properties, but not for catalysis.
“Until we came along, that kind of boron nitride was considered just inert,” Blair says. “Maybe a lubricant, maybe for cosmetics. But it didn’t have any chemical use. However, with defect engineering, the research team found that the compound had great potential for producing carbon and green hydrogen, possibly in large volumes.”
The team was surprised to discover that they could make carbon by using visible-light from boron nitride containing defects.
Blair says that to analyze the catalyst’s surface, they would place it in a small container, pressurize it with a hydrocarbon gas, such as propene, and then expose it to laser light.
“Each time, it did two things that were frustrating,” he says. “The catalyst itself emitted light that obscured any data we needed, and the student kept saying, ‘it’s getting burned’ and I would say that’s impossible. There’s no carbon on the catalyst.”
“And there was no oxygen,” adds Tetard. They were baffled.
“If we wanted to study that burning spot, it needed to be bigger,” she says.
They then placed the larger sample under an electron microscope.
“We started seeing some lines, but it’s a loose, messy powder, so it shouldn’t be ordered,” Tetard said. “But when we zoomed in some more, we saw some carbon and lots of it, with the defect-engineered boron-nitride powder clinging to the top of it.”
It was not a problem at all, but rather a fortunate discovery that would allow the production of hydrogen and carbon as by-products without any release of pollutants or greenhouse gases.
Researchers’ Credentials
Blair is a materials chemist with a PhD from the University of California at Los Angeles. He joined UCF’s faculty in 2007, and is an expert on catalysis and its applications. This includes the catalytic treatment of bio-derived compounds as fuels or chemical feedstock. He is now a research professor at the Florida Space Institute and a Fellow of the National Academy of Inventors. See the Blair Research Group site for more information.
Tetard received her doctorate in physics from the University of Tennessee, Knoxville, and joined UCF’s NanoScience Technology Center and Physics Department in 2013. She is also an associate chair and professor in the department. Tetard has a specialization in the development and application of high-resolution microscopes and spectroscopy instruments to better understand the behavior of complex materials and systems. See the Tetard Research Group site for more information.
Technology available for license
To learn more about the research team’s work and additional potential licensing or sponsored research opportunities, contact Andrea Adkins ([email protected](407-823-0138)
