Dynamics of Catalytic Nanoparticles

Abhaya K. Datye¹, Andrew Delariva¹, John Gabaldon¹, Lani Miyoshi Sanders¹, Ron Goeke¹, Qing Xu¹

Thomas Hansen^1,2, Stig Helveg², Poul Hansen², Bjerne Clausen²,

¹Ceramic and Composite Materials Center

Department of Chemical & Nuclear Engineering

University of New Mexico, Albuquerque, NM 87131, USA

²Haldor Topse A/S, Nymollevej 55, DK-2800 Lyngby, Denmark

Nanometer sized particles constitute the active phase in heterogeneous catalysts, such as those used in automotive exhaust pollution control, in energy conversion and for synthesis of chemicals.  The unique properties of heterogeneous catalysts, their activity and selectivity, depend on the size and composition of nanoparticles.  Since catalysts are used at elevated temperatures, these nanoparticles undergo coalescence and ripening leading to particle growth.  Understanding and controlling these growth processes is critical since supplies of precious metals (such as Platinum, or Gold) are limited and demand keeps increasing, for example in fuel cells.