Theoretical Investigation of the Adsorption and C–C Bond Scission of CCH3 on the (111) and (100) Surfaces of Pd: Comparison with Pt

• Published in: Journal of physical chemistry. C Vol. 117; no. 35; pp. 18131 - 18138
• Main Authors: Kim, Seok Ki, Shin, Jungho, Moon, Sang Heup, Kim, Jaehoon, Lee, Seung-Cheol
• Format: Journal Article
• Language: English
• Published: Columbus, OH American Chemical Society 05.09.2013
• Subjects: Catalysis; Catalysts: preparations and properties; Chemistry; Condensed matter: electronic structure, electrical, magnetic, and optical properties; Condensed matter: structure, mechanical and thermal properties; Electron states; Electronic structure and electrical properties of surfaces, interfaces, thin films and low-dimensional structures; Electronic transport phenomena in thin films and low-dimensional structures; Exact sciences and technology; General and physical chemistry; Methods of electronic structure calculations; Physics; Solid surfaces and solid-solid interfaces; Surfaces and interfaces; thin films and whiskers (structure and nonelectronic properties); Theory of reactions, general kinetics. Catalysis. Nomenclature, chemical documentation, computer chemistry; Density of states; Electronic properties; Adsorption energy; Theoretical study; Palladium; Hybridization; Electronic density of states; Carbon; Optimization; Electronic structure; Adsorption; Carbon carbon bond; Electron state; Density functional method; Charge density wave; Adsorption structure; Cleavage; Electron density; Catalyst
• ISSN: 1932-7447; 1932-7455
• DOI: 10.1021/jp406207p

Understanding the mechanism of C–C bond cleavage on the surface of a catalyst is central to the optimization of several reactions in the petrochemical industry. In this study, first-principles density functional theory calculations were performed to examine the adsorption properties, electronic structures, and energies of C–C bond scission in ethylidyne (CCH3) adsorbed on the (111) and (100) surfaces of Pd, and the results were compared with those of Pt. On the basis of the analyses of the electron density of states (DOS), partial charge density, and wave functions, it appears that on the adsorption of C–C, two types of bonding orbitals, namely, σC–C and πC–C, are formed. On both the low-index surfaces of Pd, the perpendicular adsorption of CCH3 was found to be the most stable configuration. Compared with the adsorption on the Pd(111) surface, the adsorption on the Pd(100) surface was less stable. On the contrary, the adsorption energies on the (111) and (100) surfaces of Pt were almost the same. Nevertheless, in both Pd and Pt, the C–C bond scission energy on the (111) surface was higher than that on the (100) surface because the hybridization of atomic carbon was more stable.