Engineers pioneer platinum shell formation process, achieve first-ever observation

August 9, 2017
A shell of platinum grows layer by layer during oxygen annealing. Credit: Pan Group / UCI

UCI researchers have devised a new method of dynamically forming a platinum shell on a metallic alloy nanoparticle core, a development that may lead to better materials for oxygen reduction reactions in fuel cells that power some cars and electronic devices. In a first, engineers were able to observe the process directly, in real time, in UCI's state-of-the-art transmission electron microscopy facility, part of the recently established Irvine Materials Research Institute.

Reported in Nature Communications, the method centers on an oxygen annealing treatment to enrich the concentration of the metal on the platinum-cobalt nanomaterial core, a more effective procedure than traditional acid leaching or reductive annealing, according to the research team.

"A deeper understanding of platinum shell formation is critical for synthesis and structural control of platinum-metallic nanoparticles," said team leader Xiaoqing Pan, Henry Samueli Endowed Chair in Engineering and professor of chemical engineering & science at UCI. "We were able to achieve atomic-scale observation of the reaction process at atmospheric pressures in our TEM, something that has never been successfully accomplished until now."

Pan, who's also the inaugural director of the Irvine Materials Research Institute and a professor of physics & astronomy, said his group's work "may open a new avenue to study gas-solid interactions at atomic scale under the atmospheric pressure at which many real gas-phase reactions take place."

The project was supported by IMRI and the National Science Foundation.

Explore further: Rough surfaces provide additional sites for energy-generating reactions in fuel cells

More information: Sheng Dai et al. In situ atomic-scale observation of oxygen-driven core-shell formation in Pt3Co nanoparticles, Nature Communications (2017). DOI: 10.1038/s41467-017-00161-y

Related Stories

Study reveals exactly how low-cost fuel cell catalysts work

August 3, 2017

In order to reduce the cost of next-generation polymer electrolyte fuel cells for vehicles, researchers have been developing alternatives to the prohibitively expensive platinum and platinum-group metal (PGM) catalysts currently ...

Recommended for you

Artificial photosynthesis gets big boost from new catalyst

November 20, 2017

A new catalyst created by U of T Engineering researchers brings them one step closer to artificial photosynthesis—a system that, just like plants, would use renewable energy to convert carbon dioxide (CO2) into stored chemical ...

Scientific advances can make it easier to recycle plastics

November 17, 2017

Most of the 150 million tons of plastics produced around the world every year end up in landfills, the oceans and elsewhere. Less than 9 percent of plastics are recycled in the United States, rising to about 30 percent in ...

The spliceosome—now available in high definition

November 17, 2017

UCLA researchers have solved the high-resolution structure of a massive cellular machine, the spliceosome, filling the last major gap in our understanding of the RNA splicing process that was previously unclear.

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.