Smaller Is Better in the Viscous Zone
When matter is in this transitional state, a catalyst can achieve its utmost potential with the right combination of catalyst particle size and temperature, reports Duke University researchers
Story content courtesy of Duke University News, US
This finding could have broad implications in almost every catalyst-based reaction, according to Professors Stefano Curtarolo and Jie Liu at Duke, who reported their findings in the journal ACS-NANO. The team found that the surface-to-volume ratio of the catalyst particle – its size -- is more important than generally appreciated.
Their series of experiments were conducted using carbon nanotubes, and the scientists believe the same principles they described in their paper apply to all catalyst-driven processes. By growing the nanotubes using different catalyst particle sizes and at different temperatures, Dr. Liu was able to determine the “sweet spot” at which the nanotubes grew the fastest and longest—which happened when the particle was in its viscous state, and that smaller was better than larger. These measurements provided the experimental underpinning of Dr. Curtarolo’s hypothesis that given a particular temperature, smaller nanoparticles are more effective and efficient per unit area than larger catalysts of the same type when they reside in that dimension between solid and liquid.
The research was supported by the Office of Naval Research, the National Science Foundation, the Department of Energy and the National Council of Science and Technology (CONACYT), Mexico.