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Masel, Richard I. Thomas, Patrick Allen 2011-05-07T12:39:32Z 2011-05-07T12:39:32Z 10000-01-01 1989 A new type of Scanning Tunneling Microscope (STM) was designed and constructed to study the surface morphology of small catalyst particles. This is the first application of the STM in the study of supported metal particles. The STM was used to study the surface morphology of Au/Pd films that were sputter deposited onto mica and subsequently sintered in air, as well as equilibrium gold particles formed and supported on graphite. New structures were observed on both the film and particle samples. The surfaces are very rough on the nanometer scale range that the STM can easily resolve. The Au/Pd films were observed to deposit uniformly on atomically fat mica even at low thickness (50 A). Annealing the metal film resulted in surface roughening, and particle-like formations on the surface. The smooth film character disappeared after short annealing times, and extended annealing resulted in discontinuous film samples that could no longer be imaged with the STM. The surface roughness of small gold particles supported on graphite appeared to be dependent upon the particle size. Small particles ($$300 A) were seen to possess a wavy surface with generally smooth features. The significance of these results is greatest in the field of heterogeneous catalysis. The structures observed on these small, model catalyst materials, may provide an insight into the structure/function relationship of supported metal catalysts. Processing conditions appear to influence the surface structure of these small particles, perhaps allowing more specific catalyst preparations to be developed. Made available in DSpace on 2011-05-07T12:39:32Z (GMT). No. of bitstreams: 2 license.txt: 4922 bytes, checksum: 910b249b4beec47e7ab768910c8f966f (MD5) 9011050.pdf: 10210848 bytes, checksum: 71920034fcd1e3eb5aa8b9c66ccee9ca (MD5) Previous issue date: 1989 Item marked as restricted to the 'UIUC Users [automated]' Group (id=2) by Howard Ding (hding2@illinois.edu) on 2011-05-07T14:43:58Z Item is restricted indefinitely. Restriction data tranferred 2014-07-01T11:19:18-05:00 Original Data Group with Access UIUC Users [automated] Release Date: none Reason: ETDs are only available to UIUC Users without author permission ETDs are only available to UIUC Users without author permission U of I Only AAI9011050 (UMI)AAI9011050 http://hdl.handle.net/2142/20449 eng Copyright 1989 Thomas, Patrick Allen Engineering, Chemical A scanning tunneling microscopy study of metal films and supported gold particles text Chemical and Biomolecular Engineering Chemical Engineering University of Illinois at Urbana-Champaign Dissertation Ph.D.