Their work aims to bridge two approaches to driving the reaction – one powered by heat, the other by electricity – with the goal of discovering more efficient and sustainable ways to convert carbon dioxide into useful products.
DOE/SLAC NATIONAL ACCELERATOR LABORATORY
CREDIT: GREG STEWART/SLAC NATIONAL ACCELERATOR LABORATORY
Virtually all chemical and fuel production relies on catalysts, which accelerate chemical reactions without being consumed in the process. Most of these reactions take place in huge reactor vessels and may require high temperatures and pressures.
Scientists have been working on alternative ways to drive these reactions with electricity, rather than heat. This could potentially allow cheap, efficient, distributed manufacturing powered by renewable sources of electricity.
But researchers who specialize in these two approaches – heat versus electricity – tend to work independently, developing different types of catalysts tailored to their specific reaction environments.
A new line of research aims to change that. Scientists at Stanford University and the Department of Energy’s SLAC National Accelerator Laboratory reported today that they have made a new catalyst that works with either heat or electricity. Based on nickel atoms, the catalyst accelerates a reaction for turning carbon dioxide into carbon monoxide – the first step in making fuels and useful chemicals from CO2.
The results represent an important step toward unifying the understanding of catalytic reactions in these two very different conditions with distinct driving forces at play, said Thomas Jaramillo, professor at SLAC and Stanford and director of the SUNCAT Institute for Interface Science and Catalysis, where the research took place.
“This is a rarity in our field,” he said. “The fact that we could bring it together in one framework to look at the same material is what makes this work special, and it opens up a whole new avenue to look at catalysts in a much broader way.”
The results also explain how the new catalyst drives this key reaction faster when used in an electrochemical reactor, the research team said. Their report appeared in the print edition of Angewandte Chemie this week.
Toward a sustainable chemistry future
Finding ways to transform CO2 into chemicals, fuels, and other products, from methanol to plastics and synthetic natural gas, is a major focus of SUNCAT research. If done on a large scale using renewable energy, it could create market incentives for recycling the greenhouse gas. This will require a new generation of catalysts and processes to carry out these transformations cheaply and efficiently on an industrial scale – and making those discoveries will require new ideas.
In search of some new directions, SUNCAT formed a team of PhD students involving three research groups in the chemical engineering department at Stanford: Sindhu Nathan from Professor Stacey Bent’s group, whose research focuses on heat-driven catalytic reactions, and David Koshy, who is co-advised by Jaramillo and Professor Zhenan Bao and has been focusing on electrochemical reactions.
Nathan’s work has been aimed at understanding heat-driven catalytic reactions at a fundamental, atomic level.
“Heat-driven reactions are what’s commonly used in industry now,” she said. “And for some reactions, a heat-driven process would be challenging to implement because it may require very high temperatures and pressures to get the desired reaction to proceed.”
Driving reactions with electricity could make some transformations more efficient, Koshy said, “because you don’t have to heat things up, and you can also make reactors and other components smaller, cheaper and more modular – plus it’s a good way to take advantage of renewable resources.”
Scientists who study these two types of reactions work in parallel and rarely interact, so they don’t have many opportunities to gain insights from each other that might help them design more effective catalysts.
But if the two camps could work on the same catalyst, it would establish a basis for unifying their understanding of reaction mechanisms in both environments, Jaramillo said. “We had theoretical reasons to think that the same catalyst would work in both sets of reaction conditions,” he said, “but this idea had not been tested.”
A new avenue for catalyst discovery
For their experiments, the team chose a catalyst Koshy recently synthesized called NiPACN. The active parts of the catalyst – the places where it grabs passing molecules, gets them to react and releases the products – consist of individual nickel atoms bonded to nitrogen atoms that are scattered throughout the carbon material. Koshy’s research had already determined that NiPACN can drive certain electrochemical reactions with high efficiency. Could it do the same under thermal conditions?
To answer this question, the team took the powdered catalyst to SLAC’s Stanford Synchrotron Radiation Lightsource (SSRL). They worked with Distinguished Staff Scientist Simon Bare to develop a tiny reactor where the catalyst could expedite a reaction between hydrogen and carbon dioxide at high temperatures and pressure. The setup allowed them to shine X-rays into the reaction through a window and watch the reaction proceed.
In particular, they wanted to see if the harsh conditions inside the reactor changed the catalyst as it facilitated the reaction between hydrogen and CO2.
“People might say, how do you know the atomic structure didn’t change, making this a slightly different catalyst than the one we had previously tested in electrochemical reactions?” Koshy said. “We had to show that the nickel reaction centers still look the same when the reaction is finished.”
That’s exactly what they found when they examined the catalyst in atomic detail before and after the reaction with X-rays and transmission electron microscopy.
Going forward, the research team wrote, studies like this one will be essential for unifying the study of catalytic phenomena across reaction environments, which will ultimately bolster efforts to discover new catalysts for transforming the fuel and chemical industries.
Parts of this study were carried out at the Stanford Nano Shared Facilities, the Canadian Center for Electron Microscopy and the Center for Nanophase Materials Sciences (CNMS) at DOE’s Oak Ridge National Laboratory. CNMS and SSRL are DOE Office of Science user facilities. Major funding came from the DOE Office of Science, including support from the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub.
Citation: David M. Koshy et al., Angewandte Chemie, 6 April 2021 (10.1002/anie.202101326)
SLAC is a vibrant multiprogram laboratory that explores how the universe works at the biggest, smallest and fastest scales and invents powerful tools used by scientists around the globe. With research spanning particle physics, astrophysics and cosmology, materials, chemistry, bio- and energy sciences and scientific computing, we help solve real-world problems and advance the interests of the nation.
SLAC is operated by Stanford University for the U.S. Department of Energy’s Office of Science. The Office of Science is the single largest supporter of basic research in the physical sciences in the United States and is working to address some of the most pressing challenges of our time.
JOURNAL
Angewandte Chemie
DOI
10.1002/anie.202101326
METHOD OF RESEARCH
Experimental study
SUBJECT OF RESEARCH
Not applicable
ARTICLE TITLE
Bridging Thermal Catalysis and Electrocatalysis: Catalyzing CO2 Conversion with Carbon-Based Materials
ARTICLE PUBLICATION DATE
6-Apr-2021
COI STATEMENT
No conflict declared
Carbon dioxide IS a useful product
Can they use the same catalyst to turn lead into gold?
This research has been about turning a pile of B.S. into grant money so, yes – I think so.
I disagree. There’s no lead involved.
This is what plants do all the time. We could burn biomass and recover some of the energy. But we’ve always done that.
CO2 is the product of combustion of carbon and oxygen. You cannot set the products of combustion alight again! Set water on fire and then you will have the secret
Reminds me of cold fusion.
“Based on nickel atoms, the catalyst accelerates a reaction for turning carbon dioxide into carbon monoxide “
So they have discovered a way to transform a benign and beneficial substance like CO2 into the deadly poison CO. Amazing!
If something that actually works economically at industrial scale were developed, the logical feed stock would be CO2 from power plants. This would tank the promised land of heavily subsidized rent seekers for CO2 sequestration.
This scheme sounds crazy to me but then I am a farmer and not a scientist .
The world already has very efficient ways of turning CO2 into usable fuel and it is very cheap and does not produce any nasty byproducts .
What is it ?
Here in New Zealand we cam grow pine trees continuously on a 26 to 30 year rotation .
We harvest them for timber to build houses and many other things and we make paper and cardboard from them .
The waste is burnt to power the mills and the whole process is a cycle .
Thats good you will say.
That is untill our mentally challenged government gets involved through their sister party the Greens .
These clowns are trying to encourage investors from around the world to purchase productive farmland on our hill country and plant it in pines that will never be harvested .
They are calling this carbon farming !
The investors will be paid very well for the carbon credits for 50 years and then the land will revert to the government .
Great scheme? all the greenies are cheering untill the untended trees die and fall over in storms and then burn during our dry summer weather in 20 to 50 years time .
Instead of producing meat and wool and providing work and income for the regions money from our taxes will flow overseas to investors .
Who ever thought this scheme up must hate farming and New Zealand .
Governments are elected to govern their countries and should be looking after their countries
well being not destroying the economy in the vain hope of saving the world .
This farmland is hilly and in some places quite steep but if well farmed it can gross $1000 New Zealand per hectare in pasture each year which is spent in New Zealand and the processing industries add value as the live stock are processed and shipped overseas to feed millions .
Graham
turning carbon dioxide into carbon monoxide
=======
One more step and you will have produced coal.
For about 100 times what it costs ro dig it out of the ground.
A catalytic converter for internal combustion engines which uses waste exhaust heat to convert part of the exhaust back to fuel?
Some comments mention “perpetual motion machine” in regards to pulling co2 out of the air to make fuel to burn, exhausting co2 out again, with the help of surplus electricity from turbines and panels, that seem to make power when you don’t need it.
I was thinking Rube Goldberg would be more appropriate, because we could just continue using the fuels we are currently using, and let the plants and plankton take care of the CO2. After all, the world has greened by a remarkable 15-20% during just the satellite era and crop yields have grown amazingly.
If one just had ‘to do something for the environment’, then using the intermittent turbines and solar to do carbon capture in old oil wells or to drive the oil sands production (or any other production that could make use of the variable electricity without too much of a hassle).
In the illustration at the top of the article, it appears that the dark gray circles represent carbon atoms, the red circles oxygen atoms, but what atom do the small light gray circles represent? It would appear to be hydrogen, so that this catalyst speeds up the reaction
CO2 + H2 –> CO + H2O
This is the reverse of the water-shift reaction, which is the second reaction in steam-methane reforming. Since the water-shift reaction is exothermic, this catalyzed reaction must be endothermic, with the energy input from electricity at least as high as the energy released in the water-shift reaction.
Another question is, where does the hydrogen come from? The two most popular ways of generating hydrogen are steam-methane reforming (which is endothermic) and electrolysis of water, which requires input of electrical energy.
Carbon monoxide (CO) is toxic, and should not be released to the atmosphere, so that something needs to be done with it. If it is burned back to carbon dioxide (CO2), the energy released would be similar to the energy required to run this process, with no net benefit. There are industrial uses for carbon monoxide, but using this process to generate CO probably consumes more energy (in particular, the use of hydrogen) than would be required in other processes used to generate CO (such as incomplete combustion of natural gas in an oxygen-starved atmosphere, or steam-methane reforming without the water-shift reaction).
Other than the production of CO for industrial use, there is no net value to this process.
Where’s the hydrogen coming from? So burn massive amount of fuel to reform methane to syngas. Take the hydrogen and combine it with the CO2 from the shift reactor and make CO. Yeah, that make sense.
You could just make syngas and call it good.
Here we go again …………”please send money to help us learn how to turn prune juice into Gasoline” we think we can, possibly , hopefully, perhaps, maybe so, you betcha!
Assuming they can scale this up for practical use, just wait until the warmers go apoplectic over it. The warmers fight tooth-and-nail against mitigation. They want reduction in emissions because they determined years ago that fossil fuels are destroying. So emitting carbon for plant A and recycling it at plant B just won’t fly.
These aren’t reasonable people. Facts and logic do no dissuade them.