West LA Times

Researchers from UCLA and Lawrence Berkeley National Laboratory have achieved a scientific first by observing a chemical catalyst during an electrically charged reaction at the atomic level. This breakthrough was made possible through a newly developed technology that allows for real-time imaging of electrochemical reactions.

Electrochemical reactions, driven by electricity, are fundamental to the production of numerous everyday products, including aluminum, PVC pipe, soap, and paper. These reactions also play a critical role in batteries used in electronics, automobiles, and medical devices such as pacemakers. Moreover, they hold potential for sustainable energy production and resource management.

Copper catalysts are widely used in industrial electrochemistry to drive these reactions. However, understanding what happens to these catalysts during reactions has been challenging because atomic imaging could only be performed before and after the reactions. The collaboration between the California NanoSystems Institute at UCLA and Lawrence Berkeley National Laboratory has now overcome this limitation.

In a study published in Nature, researchers utilized a specially designed electrochemical cell to observe the atomic details of a copper catalyst during a reaction that breaks down carbon dioxide. This process is seen as a potential method for recycling greenhouse gases into fuel or other useful substances. The scientists observed liquid-like masses of copper forming and dissolving on the catalyst surface, which became pitted as a result.

"For something that is all over our lives, we actually understand very little about how catalysts work in real time," said co-author Pri Narang, professor of physical sciences at UCLA College and member of CNSI. "We now have the ability to look at what's happening at an atomic level and understand it from a theoretical standpoint."

Narang emphasized the importance of this research for sustainable energy solutions: "Everyone would benefit from turning carbon dioxide straight to fuel, but how do we do it cheaply, reliably, and at scale? This is the type of fundamental science that should move the needle in addressing those challenges."

Co-author Yu Huang highlighted the broader implications: "Any information we can get about what really happens in electrocatalysis is a tremendous help in our fundamental understanding and search for practical designs." Huang compared previous efforts without such detailed information to "throwing darts blindfolded."

The images were captured using a high-power electron microscope at Berkeley Lab's Molecular Foundry. Electron microscopy typically struggles with revealing atomic structures in liquids required for electrochemical reactions due to interference from running electricity through samples. Corresponding author Haimei Zheng and her team developed a hermetically sealed device to address these challenges.

The researchers ensured that their observations were not affected by electrical interference by conducting controlled experiments. They focused on changes occurring where the copper catalyst met the liquid electrolyte over approximately four seconds.

During this period, they noted that the copper's structure shifted from an orderly crystal lattice into an amorphous mass containing atoms and positively charged ions of copper along with water molecules. This disordered bundle flowed over the catalyst surface before returning to its crystalline structure.

"We never expected the surface to turn amorphous and then return back to the crystalline structure," said co-author Yang Liu, a UCLA graduate student in Huang's research group. "Without this special tool for watching the system in operation, we would never be able to capture that moment."

The study’s co-first authors include Qiubo Zhang and Xianhu Sun from Berkeley Lab and Zhigang Song from Harvard University. Other contributors include Sophia Betzler, Qi Zheng, Junyi Shangguan, Karen Bustillo, Peter Ercius from Berkeley Lab; Jiawei Wan affiliated with UC Berkeley; among others.

Funding for this study was provided by the Department of Energy along with support for Berkeley Lab's Molecular Foundry.

___