Catalytic converters, which were widely introduced in American vehicles in the 1970s, use precious metals as catalysts to help scrub deadly and harmful chemicals from combustion engine exhaust. As the price of precious metals has continued to rise, so has the number of catalytic converter thefts.

In recent studies appearing in and the Journal of the American Chemical Society, UCF researchers showed that they could, respectively, use atomic platinum to control pollutants and , which is crucial to removing harmful chemicals when a vehicle first starts.

Fine-tuning Platinum Atom Location

In the Nature Communications study, UCF research teams led by Fudong Liu, assistant professor in the , and Talat Rahman, distinguished Pegasus Professor in the , successfully constructed platinum single atoms with different atomic coordination environments at specific locations on ceria. Ceria is a metal oxide that helps improve catalytic reaction performance.

Liu and Rahman are also affiliated with the Catalysis Cluster for Renewable Energy and Chemical Transformations (REACT).

The platinum atoms exhibited strikingly distinct behaviors in catalytic reactions, such as carbon monoxide oxidation and ammonia oxidation in a diesel engine exhaust aftertreatment system, the researchers say.

The oxidation converts deadly carbon monoxide to carbon dioxide, and harmful ammonia to nitrogen and water molecules.

Their results suggest that the catalytic performance of single atom catalysts in targeted reactions can be maximized by optimizing their local coordination structures through simple and industrial-scalable strategies, Liu says.

鈥淏y combining electronic structure calculations with state-of-the-art experiments, the Liu and Rahman teams have made a breakthrough that can significantly benefit the heterogenous catalysis community in designing highly efficient single atom catalysts for both environmental and energy related needs,鈥� Liu says.

鈥淲e have successfully developed a facile strategy to selectively fine-tune the local coordination environment of platinum single atoms to achieve satisfactory catalytic performance in different target reactions, which will push the understanding of single-atom catalysis a significant step forward,鈥� he says.

Rahman says their collaborative work demonstrates how theory and experiments working in tandem can unveil microscopic mechanisms responsible for enhancing catalytic activity and selectivity.

Efficient Carbon Monoxide Oxidation Catalyst

In the Journal of the American Chemical Society study, Liu and collaborators from Virginia Tech and Beijing 海角直播 of Technology significantly improved the carbon monoxide purification efficiency of a platinum-ceria-alumina catalyst by 3.5 to 70 times compared to the regularly used platinum catalysts.

They did this through the precise control of coordination structures of platinum at the atomic level on an industrial-available ceria-alumina support.

鈥淭he local structure of the active site within a catalyst determines its catalytic performance,鈥� Liu says. 鈥淗owever, the precise control of the local coordination structure of active sites and the elucidation of intrinsic structure-performance relationships are of great challenges in the heterogeneous catalysis field.鈥�

鈥淲e鈥檝e worked to control the local coordination structure of metal sites at an atomic level, develop a highly efficient catalyst in environmental purification related reactions and reveal the structure-performance relationship of the newly fabricated catalysts for guiding the future catalyst design,鈥� he says.

Using a surface defect enrichment strategy, Liu and his team reported the successful fabrication of platinum atomic single-layer and platinum single-atom structures with precisely controlled local coordination environment on ceria-alumina supports.

Using high-angle annular dark-field scanning transmission electron microscopy, one of the key coauthors, Yue Lu from Beijing 海角直播 of Technology, directly observed that the platinum atomic single-layer and platinum single-atom structures showing 100% metal exposure were embedded into ceria lattice or adsorbed on ceria surface.

The embedded platinum atomic single-layer site showed the highest efficiency in carbon monoxide purification, which was 3.5 times of that on the adsorbed platinum atomic single-layer and 10 to 70 times of that on platinum single-atom sites.

In collaboration with Hongliang Xin鈥檚 research group at Virginia Tech, from both experimental and theoretical aspects, the team concluded that the unique embedded platinum atomic single-layer structure could promote the activation of interfacial oxygen species and thus benefit the carbon monoxide oxidation at low temperatures.

The work is highly important because it will help the environmental catalysis community better design more active metal catalysts with 100% metal utilization efficiency for targeted environmental applications, Liu says.

鈥淲e showed how to control and utilize the structures of metal single-atom, atomic single-layer and cluster sites in emission control related reactions, and how to understand their structure-performance relationship using both experimental and theoretical simulation approaches,鈥� Liu says. 鈥淭his will pave the way for future environmental catalyst design at the atomic level and achieve high efficiency in practical applications.鈥�

Authors and Acknowledgements for the Nature Communications Study

Study co-authors were vitiating doctoral student Wei Tan, postdoctoral scholar Shaohua Xie, research scientist Duy Le’12PhD and doctoral student 聽Dave Austin ’22MA from UCF; Weijian Diao from Villanova 海角直播; Meiyu Wang, Fei Gao and Lin Dong from Nanjing 海角直播; Ke-Bin Low from BASF Corporation; Sampyo Hong from Brewton-Parker College; and Lu Ma and Steven Ehrlich from the National Synchrotron Light Source II (NSLS-II), Brookhaven National Laboratory.

The study was supported with funding from the U.S. National Science Foundation grant and Startup Fund (Liu) from UCF. Xie was partially supported by UCF鈥檚 Preeminent Postdoctoral program.

Licensing Opportunities

The low-temperature catalyst invention is available for . Contact Raju Nagaiah at UCF鈥檚 Office of Technology Transfer for more information.

Authors and Acknowledgements for the Journal of the American Chemical Society Study

Study co-authors were Shaohua Xie and Kailong Ye from UCF; Liping Liu from Virginia Tech; Chunying Wang, Yaobin Li and Yan Zhang from the Chinese Academy of Sciences; Sufeng Cao and Maria Flytzani-Stephanopoulos from Tufts 海角直播; Weijian Diao from Villanova 海角直播; Jiguang Deng from Beijing 海角直播 of Technology; Wei Tan, a visiting doctoral student at UCF from Nanjing 海角直播; and Lu Ma and Steven Ehrlich from the National Synchrotron Light Source II (NSLS-II), Brookhaven National Laboratory.

The work was supported by the Startup Fund (Liu) from UCF and UCF鈥檚 Preeminent Postdoctoral program (Xie).

Researcher Credentials

Liu is an assistant professor in the Department of Civil, Environmental, and Construction Engineering, part of UCF鈥檚 , and a core faculty in the Catalysis Cluster for Renewable Energy and Chemical Transformations (REACT) at UCF. Prior to his appointment at UCF, he worked at BASF Corporation as a senior chemist developing new concepts and catalyst technologies for vehicle emission control. Now, his research interests are mainly focused on heterogeneous catalysis for pollution control, greenhouse gas reduction/ultilization and clean energy source conversion. These topics include single atom catalysis, nanomaterial synthesis and catalysis, automotive emission control, CO₂ and CH₄ utilization, H₂ production, etc. Liu has published 121 peer reviewed papers with more than 9,200 citations and H-index of 48 (Google Scholar), four book chapters and applied 41 patents in environmental catalysis field.

Rahman is a trustee chair professor and Pegasus Professor in the Department of Physics, part of UCF鈥檚 , and leads the faculty cluster in Renewable Energy and Chemical Transformations (REACT) at UCF. She joined UCF as chair of physics in 2006, prior to which she was a university distinguished professor at Kansas State 海角直播. Her research interests are in computational design of functional nanomaterials through microscopic understanding of their physical and chemical properties. At UCF, she has led the effort to transform undergraduate instructions by infusing active learning environments. She is a fellow of the American Association for the Advancement of Science; the American Physical Society; AVS: Science and Technology of Materials, Interfaces and Processing; and Royal Society of Chemistry (UK). She is also the recipient of several professional awards including the Research Incentive and Excellence awards from UCF, Visiting Miller Professorship from 海角直播 of California-Berkeley, Alexander von Humboldt Research Prize, Higuchi Research award from the 海角直播 of Kansas, and the Distinguished Graduate Faculty award, Kansas State 海角直播. She has published more than 320 refereed papers, mentored over three dozen doctoral students, and engaged in promoting scientific collaborations in developing countries. Her work has been cited over 10,700 times. She has also been involved in efforts to promote the participation of women and minorities, particularly through the Bridge program of American Physical Society.

The conference, which has been held annually for over 20 years, advertises itself as the 鈥渓argest innovation pipeline on the planet.鈥� It has connected over 20,000 inventions with industry partners.

Bruder and Welch鈥檚 invention, which is awaiting a patent, resulted from research looking for ways to improve wearable headgear people use when entering AR environments. The new tech allows the user to magnify objects in real time, mimicking how our eyes naturally magnify and adjust objects with the blink of an eye.

Current AR technology allows users to magnify objects but only from photos or by activating other steps in the headgear. Bruder and Welch鈥檚 invention, however, implements machine learning to allow users to focus and react in real time. Users can even utilize hand gestures to customize the degree of magnification.

The team鈥檚 initial research shows the technology can be applied to magnify heads, allowing users to observe facial expressions in greater detail. Users can also gain a tactical advantage by magnifying objects such as cars or equipment. In the future, Bruder expects it may be used to enhance military and commercial surveillance.

This technology has been years in the making, the collaborators say.

Bruder has a master鈥檚 degree and a doctorate in computer science from the 海角直播 of M眉nster in Germany. In 2016, he left his native Germany to start working at UCF, where he met Welch, a Pegasus Professor who co-directs the housed at IST. They鈥檝e been working together ever since. A year ago, they submitted an invention disclosure and began the process of commercializing their research.

鈥淏efore I joined UCF, I鈥檇 never seen this level of interest in the research I鈥檓 doing,鈥� Bruder says. 鈥淭his university, and my institute in particular, are tremendously good at making connections between basic researchers like me and people in the industry.鈥�

During the commercialization process, the Technology Transfer Office helped Bruder and Welch file for a patent, and suggested potential uses for the research they wouldn鈥檛 have imagined otherwise.

Jennifer McKinley, who leads business development for the Department of Physical Sciences, encouraged the duo to submit their innovation to the TechConnect Conference. McKinley also delivered the presentation for the award-winning technology in November on behalf of the research team. The technology was also recently recognized at the 2021 Spatial User Interaction Conference, receiving the 鈥淏est Poster/Demo Award.

Welch is no stranger to innovation. Since arriving at UCF, his research has helped produce at least 10 patents.

Others connected with UCF were also recognized at the conference, held late last month.

This year, materials science and engineering grad Christina Drake 鈥�07PhD participated in the Innovation Showcase, with a nanoparticle disinfectant spray her company, Kismet Technologies, is developing in collaboration with two other UCF professors. At the 2020 virtual conference, Assistant Professor of Environmental Engineering Fudong Liu received a Defense Innovation Award for his work using catalysts to minimize pollutants in engine exhaust.

The 2020 TechConnect Defense Innovation Award is a recognition for a technology that removes more than 90 percent of pollutants from engine exhaust at low temperatures by utilizing novel environmental catalysts with universal, scalable fabrication techniques. The award recognizes the best technologies submitted to the conference for their potential to positively impact national security.

Engineering Professor Fudong Liu and his environmental catalysis team member Shaohua Xie developed the technology with an eye toward automakers, who need to meet increasingly stringent government emissions standards. But the tech also has a number of potential applications.

Liu joined the Department of Civil, Environmental and Construction Engineering and the university鈥檚 Catalysis Cluster for Renewable Energy and Chemical Transformations in 2018. He has a doctorate in environmental science and has published more than 80 peer-reviewed journal articles with more than 6,300 citations.

Catalysts spark and speed up chemical reactions and are critical in industries that transform raw materials into products. UCF鈥檚 tech expedites chemical reactions to help reduce harmful emissions from automobiles. The Office of Technology Transfer showcases innovations at national conferences to identify prospective licensing partners to transform inventions into impactful products.

The conference brings together defense, private industry, federal agencies and academia together to accelerate state-of-the-art technology solutions that will safeguard national security. Typically, the conference is held in a city, but this year it is virtual because of COVID-19.

Other technologies UCF will showcase at the conference Nov. 17-19 are:

• An autograft-extracting device for autologous osteochondral transplantation.

Engineering Professor Sang-Eun Song developed a bone and/or cartilage removal device to harvest a precisely defined autologous graft for mosaicplasty, a technique in which bone and cartilage (‘osteochondral’) lesions are repaired by harvesting and transplanting cylindrical plugs of bone and cartilage.

• Uncooled Frequency Selective LWIR detector for Chemical Sensing.

CREOL and NanoScience Technology Center Researcher Debashis Chanda developed a chemical sensing system that narrows emission lines of various gas molecules, which cannot be detected with present day broadband detectors.

A UCF-led team of scientists and engineers are hunting for ways to reduce the need for noble metals such as platinum in promoting chemical reactions by reducing the total amount needed or swapping it out for other materials that are just as effective. The team will explore whether single atoms of platinum, palladium or other metal-based materials will work just as effectively if properly prepped on other inexpensive surfaces such as ceria or zinc oxide. The National Science Foundation recently gave them more than $750,000 grant to see if the approach will work.

鈥淚f we can do it, we will have discovered a material that can reduce the noble metals usage or replace noble metals at a fraction of the cost,鈥� says Talat Rahman, a physics professor, who is leading the project. 鈥淥nce our fundamental research can establish the propensity of the proposed single atom catalysts and nano catalyst and we can show how to prepare them effectively, they will be good candidates for large scale applications for both environmental and energy sustainability.鈥�

In other words, if highly stable and effective single atom catalysts can be predicted and synthesized facilely, industries would need less than one tenth of the present noble metals to achieve similar or even higher catalytic performance, to purify the air we breathe, to clean the water we drink, to produce vital chemical build-blocks, or to generate clean fuels such as hydrogen that drive our mobility. The substitution of noble metals using single atom base metals as catalysts will further reduce the production cost without sacrificing performance, making the process more environment friendly and energy sustainable.

Rahman, UCF engineering assistant professor Fudong Liu and Brewton-Parker College physics associate professor Sampyo Hong will work with undergraduate and graduate students including several from underrepresented groups as part of the project.

Sounds like an easy endeavor, but scientists and engineers have been trying to crack this mystery for years. The challenge is that at the quantum level, smaller than what can be seen with standard microscopes, the rules of physics in the macro world don鈥檛 appear to apply. Objects don鈥檛 always behave the way we would expect, making it even more difficult to anticipate and predict reactions. That鈥檚 why the interdisciplinary nature of this team is one of its strength, Rahman said. Bringing together chemistry, physics, engineering and material science expertise was the key to coming up with the idea.

Rahman and Liu have been working on this idea for a while. They are members of the Renewable Energy and Chemical Transformation (REACT) cluster at UCF. Rahman collaborated with Hong while he was a research associate at UCF before taking the teaching position at Brewton-Parker.

鈥淚t鈥檚 exciting work that my experimental team can closely work with theory experts like Dr. Rahman and Dr. Hong on such a timely research topic,鈥� Liu says. 鈥淚n this project, we will move away from the Edisonian method of trial and error and move towards computation and experiments working in tandem.鈥�

Instead of starting synthesis of a catalyst by using age old recipes of mixing various components etc., Rahman, Hong and their students will first carry out modeling and simulation of catalyst nanostructures based on insights that they have already gained from many years of work in the field which have helped them develop certain hypothesis and a set of guidelines for arriving at the ideal local atomic environment that could facilitate a chemical reaction of interest.

The team鈥檚 simulations will further modify these guidelines or establish new ones, which would then set the stage for the synthesis and experimental characterization of the proposed catalysts. Once experimental results on rationally designed catalysts are obtained from Liu and his team, the theory and computation team will help rationalize the results and fine tune the guidelines leading to more experiments, more characterization, more computation and repeat of the feedback cycle. This is a paradigm shift in single catalysis and nano catalysis research.

An important part of the project to the researchers is the ability to give hands-on experience to students of color. Rahman serves as the site leader for the American Physical Society Bridge Program, which aims to increase the number of physics doctorates awarded to students of underrepresented groups.

鈥淓ven before the internet ushered the technological revolution, scientists were very busy finding common language and techniques so individuals from different disciplines could bring their expertise together to solve some of the grand challenges of our times,鈥� Rahman says. 鈥淣ow it has become almost a requirement that this be the case. It is thus our responsibility to train our students in interdisciplinary thinking and collaborative research to tackle big scientific and technological issues, such as discovering cost effective materials to serve our energy needs. Such training not only opens new doors for our students, it also helps develop a holistic and competitive work force ready to anticipate the new challenges of future generation.鈥�

Liu agrees.

鈥淲e, as engineers, usually try to solve many problems using our hands-on experience,鈥� he says. 鈥淭he world is changing so fast requiring both efficiency and accuracy, and theoretical prediction and machine learning can greatly help us to narrow down the targets we want to shoot in catalysis research. I am very glad to be part of this excellent project team, so I can train the next generation of catalysis engineers in a different way than I had before.鈥�

Liu joined UCF in 2018. He has a doctorate in environmental science and has published more than 70 peer-reviewed journal articles.

Rahman joined UCF in 2006. She has multiple degrees including a doctorate in physics. REACT cluster. She is a frequent speaker at national and international conferences and has published more than 250 peer-reviewed articles.