Formation of Second-Generation Nanoclusters on Metal Nanoparticles Driven by Reactant Gases.
Heterogeneous catalysis occurs at the interface between a solid catalyst and the reactants. The structure of metal catalyst nanoparticles at the metal-gas interface is a key factor that determines catalytic selectivity and activity. Here we report that second-generation nanoclusters are formed on the initial catalyst nanoparticles as a result of interaction with the reactant molecules when the nanoparticles are in a gas phase at Torr pressure or higher. The formation of the second-generation nanoclusters is manifested by a decrease of the average coordination number of the metal atoms and a shift of their core level energies in the presence of gases. The formation of second-generation nanoclusters increases the number of undercoordinated sites, which are the most active for catalysis in many cases.
Department of Chemical and Petroleum Engineering and Department of Chemistry, University of Kansas , Lawrence, Kansas 66045, United States.
Franklin Feng
FF
Tao
Department of Chemical and Petroleum Engineering and Department of Chemistry, University of Kansas , Lawrence, Kansas 66045, United States.
Luan
L
Nguyen
Department of Chemical and Petroleum Engineering and Department of Chemistry, University of Kansas , Lawrence, Kansas 66045, United States.
Shiran
S
Zhang
Department of Physics, Yeshiva University , New York, New York 10016, United States.
Yuanyuan
Y
Li
Department of Chemical and Petroleum Engineering and Department of Chemistry, University of Kansas , Lawrence, Kansas 66045, United States.
Yu
Y
Tang
Department of Chemistry, Georgia Institute of Technology , Atlanta, Georgia 30332, United States.
Lei
L
Zhang
Department of Physics, Yeshiva University , New York, New York 10016, United States.
Anatoly I
AI
Frenkel
Department of Chemistry, Georgia Institute of Technology , Atlanta, Georgia 30332, United States.
Younan
Y
Xia
Materials Science Division, Lawrence Berkeley National Lab , Berkeley, California 94720, United States.
Miquel
M
Salmeron