A Nanoscale Demonstration of Hydrogen Atom Spillover and Surface Diffusion Across Silica Using the Kinetics of CO2 Methanation Catalyzed on Spatially Separate Pt and Co Nanoparticles

作者：Beaumont Simon K; Alayoglu Selim; Specht Colin; Kruse Norbert; Somorjai Gabor A^*

来源：Nano Letters, 2014, 14(8): 4792-4796.

DOI：10.1021/nl501969k

• Hydrogen spillover
• nanoparticles
• catalysis
• surface diffusion
• transport limited
• CO2 methanation

Hydrogen spillover is of great importance to understanding many phenomena in heterogeneous catalysis and has long been controversial. Here we exploit well-defined nanoparticles to demonstrate its occurrence through evaluation of CO2 methanation kinetics. Combining platinum and cobalt nanoparticles causes a substantial increase in reaction rate, but increasing the spatial separation between discrete cobalt and platinum entities results in a dramatic similar to 50% drop in apparent activation energy, symptomatic of H atom surface diffusion limiting the reaction rate.

• 出版日期2014-8