MODEL CATALYSTS FABRICATED USING ELECTRON-BEAM LITHOGRAPHY AND PULSED-LASER DEPOSITION

Supported metal nanoparticles have been fabricated using electron beam lithography (EEL) and pulsed laser deposition (PLD). EEL produced ord ered two-dimensional arrays with particle diameters of 40 +/- 0.5 nm, uniform interparticle distances (230 +/- 2 nm), and uniform height (20 +/- 0.5 nm). Due to the narrow size distribution of the particles and the long-range (cm(2)) order, the arrays produced using EBL were appl ied as models for supported metal catalysts. Smaller particle sizes ca n be obtained using PLD, but with larger size and spatial distribution s of the particles. Particles fabricated with PLD have mean sizes rang ing from 2 to 50 nm, depending on the ambient pressure during depositi on. Tile nanoparticles have been characterized using TEM, AFM, UPS, an d SEM. Reaction studies of ethylene hydrogenation on Pt nanoparticle a rrays have demonstrated that detectable amounts of ethane are produced , despite the low surface area of the model catalysts.