ICC: Size and Structure Sensitivity of Metal Nanoparticle Reactivity in the Aerosol State

点击翻译按钮获取中文摘要

We propose to study the uptake and reaction of small, catalytically relevant molecules- e.g., oxygen, hydrogen, carbon monoxide, and simple unsaturated hydrocarbons- onto unsupported gold particles in the aerosol state. The gold particles will be produced evaporatively in a furnace or by thermal decomposition of a suitable metal organic precursor. Specific issues to be addressed are:Adsorption and desorption kinetics, as revealed by measurements of sticking probabilities and thermal desorption rates. These experiments will make use of an instrument developed in Roberts’ laboratory that relates changes in electric mobility to uptake and loss of sub-monolayer quantities of material.Detailed heterogeneous reaction pathways, using an instrument developed by Kasper in which aerosol photoemission spectroscopy (APES) is used to study catalytic activity in metal aerosol nanoparticles under atmospheric pressure conditions.Size-dependent effects. These experiments will be enabled by a new generation of particle electric mobility analyzers that can create monodisperse streams of selected diameter as small as 1.5 nm, a size usually considered to be the border between molecular clusters and particles.