Vibrational Spectroscopy of Acetylene Decomposition on Palladium (111) and (100) Surfaces.
Abstract
Vibrational spectra for thermal decomposition of acetylene (C2H2) on (111) and (100) surfaces of palladium obtained with high-resolution electron energy loss spectroscopy (EELS) are described. Of particular interest is the formation of CCH species on both surfaces, which are identified spectroscopically in this context for the first time. On Pd(100) CCH forms with thermal processing of chemisorbed acetylene to approximately 400K but on Pd(111) is co-adsorbed with a triple bond C-CH3 species following 300K C2H2 adsorption. With further annealing to 450K CCH is the dominant species on both surfaces. The EELS spectra indicate that both carbon atoms are involved in the CCH interaction with the surface as implied by a C-C bond order between 1 and 2. In view of recent reports of acetylene trimerization to benzene (C6H6) on Pd surfaces the EELS spectra of C6H6 and isotopic mixtures were also analyzed but no evidence of this reaction was found.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jan 16, 1984
- Accession Number
- ADA137216
Entities
People
- G. D. Waddill
- J. A. Gates
- L. L. Kesmodel
Organizations
- Indiana University Bloomington