TPD characterization of surface adsorption sites of model Ziegler–Natta polymerization catalysts

Kim, SH; Somorjai, GA

HERO ID

854054

Reference Type

Journal Article

Year

2000

HERO ID 854054
In Press No
Year 2000
Title TPD characterization of surface adsorption sites of model Ziegler–Natta polymerization catalysts
Authors Kim, SH; Somorjai, GA
Journal Applied Surface Science
Volume 161
Issue 3-4
Page Numbers 333-339
Abstract The surface adsorption sites of titanium chloride films that can be used as model Ziegler-Natta polymerization catalysts have been investigated with temperature-programmed desorption (TPD) of various probe molecules. The adsorption sites can be differentiated depending on the heat of desorption of the molecule. Two titanium chloride films were produced by electron-induced chemical vapor deposition of TiCl4 and co-deposition of Mg and TiCl4 on gold substrates. The surfaces of both films were chlorine-terminated. 1,3,5-Trimethylbenzene (mesitylene) was found to be an effective and non-destructive molecule for TPD characterization of adsorption sites on the model catalysts. The film produced by the electron-induced chemical vapor deposition had a distribution of adsorption sites that were not thermodynamically stable and subject to high-temperature annealing, while the film prepared by the co-deposition had a stable surface structure that was composed of domains of the MgCl2(001) basal plane structure. (C) 2000 Elsevier Science B.V. All rights reserved.
Doi 10.1016/s0169-4332(00)00131-8
Wosid WOS:000088701500005
Url http://linkinghub.elsevier.com/retrieve/pii/S0169433200001318
Is Certified Translation No
Dupe Override No
Is Public Yes
Keyword Ziegler-Natta catalyst; adsorption site; temperature-programmed desorption; chemical vapor deposition; TiCl4; MgCl2
Is Qa No