Many modern industrial processes depend on complex chemistry. Take fertilizer production, for example: to make it, companies must first produce ammonia, a key ingredient.
These chemical processes need ingredients of their own — catalysts, which speed up reactions without being consumed or creating unwanted byproducts.
One emerging type of catalyst — known as a "single-atom" or "atomically dispersed" catalyst — is getting a lot of attention for its potential to make industrial processes cleaner and more efficient. Academic journals are overflowing with studies on them.
Now, thanks to an invitation from the editor of a top scientific journal, a University of Virginia chemical engineer is making sense of all the changes and points the way for future breakthroughs.
How It Happened
An editor at Nature Chemistry recently noticed a standout journal article peer review written by Jason Bates , an assistant professor of engineering at UVA's School of Engineering and Applied Science. The editor emailed an invitation: Could Bates write a perspective on how to investigate atomically dispersed catalysts to ensure proper rigor and reproducibility?
Publication submissions in this new area of catalysis research are surging, the editor told Bates, but too often, the researchers' claims promise more than they deliver based on their science.
Bates agreed. His article, "Progress and pitfalls in designing heterogeneous catalysts with molecular precision," was published by Nature Chemistry in February.
"I hope it will guide research toward the right directions so that we can discover new things faster," Bates said, "without generating misleading conclusions."
What Are Atomically Dispersed Catalysts?
Catalysts are widely used in industry to increase efficiency, lower costs and reduce environmental impact. They typically fall into two categories.
Homogeneous catalysts, dissolved in liquid, offer precise control and consistent results. But they are expensive and best suited for high-value, small-scale production, like pharmaceuticals.
Heterogeneous catalysts, which are solid and used at large scales, power industries like fuel refining and fertilizer production. These usually consist of tiny clusters of metal atoms — like platinum or iron — spread over a support material.
But traditional heterogeneous catalysts can wear down under tough operating conditions. Over time, their structure and effectiveness degrade.
Atomically dispersed catalysts aim to combine the best of both worlds: the precision of homogeneous systems with the durability and scalability of heterogeneous ones. Instead of metal clusters, these use single metal atoms anchored to a solid surface, which serve as the reaction sites.
"They're attractive," Bates said, "because you can design them with the specificity of a homogeneous catalyst, but they function in practical environments like a heterogeneous one."
This matters because many industrial processes have already reached peak efficiency with current technology. Take ammonia production again: while the process itself emits little CO₂, making the hydrogen it requires does — because that hydrogen comes from fossil fuels.
"So, we need new ways to make hydrogen in a less carbon-intensive way," Bates said. "Atomically dispersed catalysts could be part of the solution."
Putting the Puzzle Together
Atomically dispersed catalysts allow for precise design — but they're still complex systems. Testing and characterizing them requires painstaking work, which Bates argues is too often skipped or rushed.
He likens their structure to a jigsaw puzzle. There are many methods for finding the pieces, but they must be assembled to get a complete picture.
"Many researchers will put down one piece and say, now I know what the rest of the puzzle looks like without considering the alternative hypotheses and techniques," he said. "The reality of research in this area is that you almost never can get every piece of the puzzle."
Bates believes the field needs to slow down and focus on repeatable, rigorous science. Only then, he argues, can researchers confidently understand what they've made — and how to make it better.
His paper has already struck a chord. E. Charles Sykes, a professor of chemistry at Tufts University who reviewed Bates' work for Nature Chemistry, agreed with the call for caution.
"The myriad reports of new atomically dispersed catalysts are often not well-characterized or tested. This limits fundamental insight," Sykes said. "Jason's review points out many of the common pitfalls and should serve as a guide for the ever-growing community."
