Atomic-level study provides real-time view of fuel cell catalysts

Fuel cells use platinum catalysts that enable the reactions that convert chemical energy into electricity. Alloying platinum with noble metals such as cobalt reduces the overall cost, but these alloyed catalysts can vary in performance.

An ORNL team is said to have used scanning transmission electron microscopy to track atomic reconfigurations in individual platinum-cobalt nanoparticle catalysts as the particles were heated inside the microscope.

The in-situ measurements - acquired in real time in the vacuum of the microscope column - allowed the researchers to collect atomic level data that could not be obtained with conventional microscopy techniques.

The study is published as Surface faceting and elemental diffusion behavior at atomic scale for alloy nanoparticles during in situ annealing in Nature Communications.

“This is the first time individual nanoparticles have been tracked this way - to image the structural and compositional changes at the atomic level from the start of an annealing process to the finish,” said Karren More, ORNL co-author.