Tag Archives: University of Illinois at Chicago (UIC)

Alloy nanoparticles make better catalysts

A Jan. 4, 2021 news item on Nanowerk describes new insights into nanoscale catalysts derived from work at the US Argonne National Laboratory,

Catalysts are integral to countless aspects of modern society. By speeding up important chemical reactions, catalysts support industrial manufacturing and reduce harmful emissions. They also increase efficiency in chemical processes for applications ranging from batteries and transportation to beer and laundry detergent.

As significant as catalysts are, the way they work is often a mystery to scientists. Understanding catalytic processes can help scientists develop more efficient and cost-effective catalysts. In a recent study, scientists from University of Illinois Chicago (UIC) and the U.S. Department of Energy’s (DOE) Argonne National Laboratory discovered that, during a chemical reaction that often quickly degrades catalytic materials, a certain type of catalyst displays exceptionally high stability and durability.

The catalysts in this study are alloy nanoparticles, or nanosized particles made up of multiple metallic elements, such as cobalt, nickel, copper and platinum. These nanoparticles could have multiple practical applications, including water-splitting to generate hydrogen in fuel cells; reduction of carbon dioxide by capturing and converting it into useful materials like methanol; more efficient reactions in biosensors to detect substances in the body; and solar cells that produce heat, electricity and fuel more effectively.

A January 4, 2021 Argonne National Laboratory news release (also on EurekAlert) by Savannah Mitchem fills in some details,

In this study, the scientists investigated “high-entropy” (highly stable) alloy nanoparticles. The team of researchers, led by Reza Shahbazian-Yassar at UIC, used Argonne’s Center for Nanoscale Materials (CNM), a DOE Office of Science user facility, to characterize the particles’ compositions during oxidation, a process that degrades the material and reduces its usefulness in catalytic reactions.

“Using gas flow transmission electron microscopy (TEM) at CNM, we can capture the whole oxidation process in real time and at very high resolution,” said scientist Bob Song from UIC, a lead scientist on the study. “We found that the high-entropy alloy nanoparticles are able to resist oxidation much better than general metal particles.”

To perform the TEM, the scientists embedded the nanoparticles into a silicon nitride membrane and flowed different types of gas through a channel over the particles. A beam of electrons probed the reactions between the particles and the gas, revealing the low rate of oxidation and the migration of certain metals — iron, cobalt, nickel and copper — to the particles’ surfaces during the process.

“Our objective was to understand how fast high-entropy materials react with oxygen and how the chemistry of nanoparticles evolves during such a reaction,” said Shahbazian-Yassar, UIC professor of mechanical and industrial engineering at the College of Engineering.

According to Shahbazian-Yassar, the discoveries made in this research could benefit many energy storage and conversion technologies, such as fuel cells, lithium-air batteries, supercapacitors and catalyst materials. The nanoparticles could also be used to develop corrosion-resistant and high-temperature materials.

“This was a successful showcase of how CNM’s capabilities and services can meet the needs of our collaborators,” said Argonne’s Yuzi Liu, a scientist at CNM. “We have state-of-the-art facilities, and we want to deliver state-of-the-art science as well.”

Here’s a link to and a citation for the paper,

In Situ Oxidation Studies of High-Entropy Alloy Nanoparticles by Boao Song, Yong Yang, Muztoba Rabbani, Timothy T. Yang, Kun He, Xiaobing Hu, Yifei Yuan, Pankaj Ghildiyal, Vinayak P. Dravid, Michael R. Zachariah, Wissam A. Saidi, Yuzi Liu, and Reza Shahbazian-Yassar. ACS Nano 2020, 14, 11, 15131–15143 DOI: https://doi.org/10.1021/acsnano.0c05250 Publication Date:October 20, 2020 Copyright © 2020 American Chemical Society

This paper is behind a paywall.

Below is one of my favourite types of video work, a ‘blob video’ from the University of Illinois showing the alloy nanoparticles as they oxidate,

Video of transmission electron microscopy, performed at Argonne’s CNM, showing the oxidation of high-entropy nanoparticles in air at 400 °C, sped up by a factor of four. The oxidation process is depicted by the dissolution of the edges of the nanoparticles in the video. (Image by University of Illinois.)

Science denial is not limited to the political right

These days, climate is the most likely topic to bring up charges of having anti-science views and/or ‘right wing’ thinking but according to a Sept. 19, 2017 news item on phys.org ‘left wing’ thinkers can also reject science,

In the wake of Hurricanes Harvey and Irma, many claims have been made that science denial, particularly as it relates to climate change, is primarily a problem of the political right.

But what happens when scientific conclusions challenge liberals’ attitudes on public policy issues, such as gun control, nuclear power or immigration?

A new study from social psychologists at the University of Illinois at Chicago [UIC] and published online in Social Psychological and Personality Science suggests people of all political backgrounds can be motivated to participate in science denial.

A Sept. 19, 2017 University of Illinois at Chicago news release (also on EurekAlert), which originated the news item, delves further,

UIC researchers Anthony Washburn, a graduate student in psychology, and Linda Skitka, professor of psychology, had participants indicate their political orientation, evaluate fabricated scientific results, and, based on the data, decide what the studies concluded.

Once they were informed of the correct interpretations of the data, participants were then asked to rate how much they agreed with, found knowledgeable, and trusted the researchers’ correct interpretation.

“Not only were both sides equally likely to seek out attitude confirming scientific conclusions, both were also willing to work harder and longer when doing so got them to a conclusion that fit with their existing attitudes,” says Washburn, the lead author of the study. “And when the correct interpretation of the results did not confirm participants’ attitudes, they were more likely to view the researchers involved with the study as less trustworthy, less knowledgeable, and disagreed with their conclusions more.”

These effects were constant no matter what issue was under consideration, which included six social issues — immigration, gun control, climate change, health care reform, nuclear power and same sex marriage — and one control issue — skin rash treatment.

Rather than strictly a conservative phenomenon, science denial may be a result of a more basic desire of people wanting to see the world in ways that fit with their personal preferences, political or otherwise, according to the researchers.

The results also shed light on science denial in public discourse, Skitka added.

“Before assuming that one group of people or another are anti-science because they disagree with one scientific conclusion, we should make an effort to consider different motivations that are likely at play, which might have nothing to do with science per se,” she said.

This research fits into a larger body of work where researchers are examining what we believe and how we use or dismiss science and fact to support our positions. Chris Mooney’s article “The Science of Why We Don’t Believe Science” for the May/June 2011 issue of Mother Jones examines the issue although it is strongly weighted with examples of research into intransigent opinion associated with right wing politics (climate change, etc.).

Getting back to more recent work, here’s link to and a citation for the paper,

Science Denial Across the Political Divide; Liberals and Conservatives Are Similarly Motivated to Deny Attitude-Inconsistent Science by Anthony N. Washburn, Linda J. Skitka. Social Psychological and Personality Science DOI: https://doi.org/10.1177/1948550617731500 First Published September 14, 2017

This paper is behind a paywall.