Interaction of ethylene and hydrogen with a commercial Pd black: carbon accumulation and possible adsorbate-induced rearrangement

The interaction of hydrogen, ethylene and their mixtures with a commercial Pd black was studied. Hydrogen treatment at 300 K created a rather clean Pd surface with some residual carbon. Ethylene introduced in high hydrogen excess exerted hardly any influence on the metallic properties of Pd, as shown by X-ray and ultraviolet photoelectron spectroscopy (XPS and UPS). The carbon content did not change. Contacting Pd with ethylene in low excess of H2 or without any hydrogen changed the Pd 3d line, indicating its chemical interaction with C. Simultaneously, a new component appeared in the C 1s region at BE∽283.5 eV. It indicated the formation of Pd–C bonds, responsible for changes in the Pd valence state. Intensity drop at the near-Fermi edge region in UPS corroborated this interaction. Pd also underwent considerable structural rearrangement, as shown by the appearance of a large peak in the UP spectra at ∽8 eV, corresponding to the enrichment of the sodium carbonate impurity on the surface. This component proved to be a good indicator of surface flexibility.

[1]  M. Bäumer,et al.  Structure-Reactivity Relationships on Supported Metal Model Catalysts: Adsorption and Reaction of Ethene and Hydrogen on Pd/Al2O3/NiAl(110) , 2001 .

[2]  R. M. Lambert,et al.  Electrochemical Promotion of Rhodium-Catalyzed NO Reduction by CO and by Propene in the Presence of Oxygen , 2001 .

[3]  R. M. Lambert,et al.  Electrochemical Promotion by Sodium of the Rhodium-Catalyzed Reduction of NO by Propene: Kinetics and Spectroscopy , 2001 .

[4]  R. Schlögl,et al.  XPS, EM, and Catalytic Studies of the Accumulation of Carbon on Pt Black , 2001 .

[5]  A. Beck,et al.  Characterization of Pd Blacks by Temperature Programmed Oxidation , 2000 .

[6]  R. Schlögl,et al.  An attempt to bridge the pressure and material gap with a disperse model catalyst for low-temperature alkane reforming , 2000 .

[7]  R. Prins,et al.  Foils, Films, and Nanostructured Surfaces: A Comparative XPS and AFM Study of Model Catalyst Surfaces† , 2000 .

[8]  D. Ramaker,et al.  A new model describing the metal-support interaction in noble metal catalysts , 1999 .

[9]  G. Somorjai,et al.  Molecular Studies of Catalytic Reactions on Crystal Surfaces at High Pressures and High Temperatures by Infrared−Visible Sum Frequency Generation (SFG) Surface Vibrational Spectroscopy , 1999 .

[10]  J. N. Andersen,et al.  Adsorption of acetylene and hydrogen on Pd(111) : Formation of a well-ordered ethylidyne overlayer , 1998 .

[11]  G. Somorjai,et al.  Palladium-catalyzed hydrogenation without hydrogen: the hydrodechlorination of chlorofluorocarbons with solid state hydrogen over the palladium (111) crystal surface and its implications , 1997 .

[12]  Z. Paâl,et al.  Transformations of n-Hexane over Platinum Black Characterized by Electron Spectroscopy at Reaction Temperature , 1997 .

[13]  I. Dékány,et al.  Sorption and Microcalorimetric Investigations of Palladium/Hydrogen Interactions on Palladium−Graphimet Intercalation Catalyst , 1997 .

[14]  L. Liotta,et al.  Effect of sodium on the electronic properties of Pd/silica−alumina catalysts , 1996 .

[15]  G. Somorjai.  The flexible surface: new techniques for molecular level studies of time dependent changes in metal surface structure and adsorbate structure during catalytic reactions , 1996 .

[16]  A. Rossi,et al.  Particle size and metal support interaction effects in pumice supported palladium catalysts , 1995 .

[17]  L. Liotta,et al.  Pumice as Support for Metal Catalysts. , 1995 .

[18]  A. Benedetti,et al.  Pumice-Supported Palladium Catalysts: II. Selective Hydrogenation of 1,3-Cyclooctadiene , 1994 .

[19]  R. Schlögl,et al.  Photoelectron spectroscopy of polycrystalline platinum catalysts , 1992 .

[20]  R. Antón,et al.  On the origin of a lattice expansion in palladium and PdAu vapour deposits on various substrates , 1991 .

[21]  F. Zaera.  Mechanisms for ethylene hydrogenation and hydrogen-deuterium exchange over platinum(111) , 1990 .

[22]  H. Hoffmann,et al.  Determination of the bonding and orientation of ethylene on Pd(111) by near-edge x-ray absorption fine structure and photoelectron spectroscopy , 1990 .

[23]  R. Schlögl,et al.  Identification of the state of palladium in various hydrogenation catalysts by XPS , 1990 .

[24]  A. Frennet,et al.  Kinetics of reactions catalyzed by metals: role of surface hydrocarbon residues in conversion of alkanes on Pt , 1990 .

[25]  F. Solymosi,et al.  Effects of potassium adlayer on the adsorption and desorption of hydrogen on a Pd(100) surface , 1989 .

[26]  H. Freund,et al.  Influence of alkali co-adsorption on the adsorption and reaction of CO2 on Pd(111) , 1989 .

[27]  A. Reller,et al.  The Microstructure of Selective Palladium Hydrogenation Catalysts Supported on Calcium Carbonate and Modified by Lead (Lindlar Catalysts), Studied by Photoelectron Spectroscopy, Thermogravimetry, X‐Ray Diffraction, and Electron Microscopy , 1987 .

[28]  R. M. Lambert,et al.  Photoelectron spectroscopy and heterogeneous catalysis: Benzene and ethylene from acetylene on palladium (111) , 1983 .

[29]  S. Louie,et al.  Interaction of hydrogen with a Pd(111) surface , 1983 .

[30]  H. Bonzel,et al.  C(1s) spectroscopy of hydrocarbons adsorbed on Pt(111) , 1983 .

[31]  J. Fuggle,et al.  Electronic structure and surface kinetics of palladium hydride studied with x-ray photoelectron spectroscopy and electron-energy-loss spectroscopy , 1982 .

[32]  J. Konvalinka,et al.  Sorption and temperature-programmed desorption of hydrogen from palladium and from palladium on activated carbon , 1977 .

[33]  G. Ertl,et al.  Interaction of NO and O2 with Pd(111) surfaces. I. , 1977 .

[34]  Z. Paâl,et al.  Radiotracer studies on the interaction of hydrogen with platinum black catalysts , 1973 .

[35]  D. Eastman,et al.  Photoemission Studies of Energy Levels in the Palladium-Hydrogen System , 1971 .