Dynamic Surface Processes of Nanostructured Pd2Ga Catalysts Derived from Hydrotalcite-Like Precursors

The stability of the surface termination of intermetallic Pd2Ga nanoparticles and its effect on the hydrogenation of acetylene was investigated. For this purpose, a precursor synthesis approach was applied to synthesize supported intermetallic Pd2Ga nanoparticles. A series of Pd-substituted MgGa-hydrotalcite (HT)-like compounds with different Pd loading was prepared by coprecipitation and studied in terms of loading, phase formation, stability and catalytic performance in the selective hydrogenation of acetylene. Higher Pd loadings than 1 mol % revealed an incomplete incorporation of Pd into the HT lattice, as evidenced by XANES and TPR measurements. Upon thermal reduction in hydrogen, Pd2Ga nanoparticles were obtained with particle sizes varying with the Pd loading, from 2 nm to 6 nm. The formation of intermetallic Pd2Ga nanoparticles led to a change of the CO adsorption properties as was evidenced by IR spectroscopy. Dynamic changes of the surface were noticed at longer exposure times to CO and higher c...

[1]  R. Schlögl,et al.  Surface dynamics of the intermetallic catalyst Pd2Ga, Part I – Structural stability in UHV and different gas atmospheres , 2014 .

[2]  R. Schlögl,et al.  Surface dynamics of the intermetallic catalyst Pd2Ga, Part II - Reactivity and stability in liquid-phase hydrogenation of phenylacetylene , 2014 .

[3]  Chao Ma,et al.  Partial hydrogenation of acetylene using highly stable dispersed bimetallic Pd–Ga/MgO–Al2O3 catalyst , 2014 .

[4]  P. Midgley,et al.  Revealing the Atomic Structure of Intermetallic GaPd2 Nanocatalysts by using Aberration‐Corrected Scanning Transmission Electron Microscopy , 2013 .

[5]  K. Föttinger The effect of CO on intermetallic PdZn/ZnO and Pd2Ga/Ga2O3 methanol steam reforming catalysts: A comparative study , 2013 .

[6]  P. Claus,et al.  Kinetics and reactor modeling of a Pd-Ag/Al2O3 catalyst during selective hydrogenation of ethyne , 2012 .

[7]  D. Ferri,et al.  Comparative study of hydrotalcite-derived supported Pd2Ga and PdZn intermetallic nanoparticles as methanol synthesis and methanol steam reforming catalysts , 2012 .

[8]  D. Teschner,et al.  Alloys in catalysis: phase separation and surface segregation phenomena in response to the reactive environment , 2012 .

[9]  R. Schlögl,et al.  In situ study of the formation and stability of supported Pd2Ga methanol steam reforming catalysts , 2012 .

[10]  N. López,et al.  Promoters in the hydrogenation of alkynes in mixtures: insights from density functional theory. , 2012, Chemical communications.

[11]  Matthias Friedrich,et al.  Synthesis and catalytic properties of nanoparticulate intermetallic Ga-Pd compounds. , 2011, Journal of the American Chemical Society.

[12]  R. Schlögl,et al.  Intermetallic Compound Pd2Ga as a Selective Catalyst for the Semi-Hydrogenation of Acetylene: From Model to High Performance Systems† , 2011 .

[13]  R. Schlögl,et al.  Pd-Ga intermetallic compounds as highly selective semihydrogenation catalysts. , 2010, Journal of the American Chemical Society.

[14]  D. Ferri,et al.  The Effect of the State of Pd on Methane Combustion in Pd-Doped LaFeO3 , 2010 .

[15]  S. Kühl,et al.  Phase-pure Cu,Zn,Al Hydrotalcite-like Materials as Precursors for Copper rich Cu/ZnO/Al2O3 Catalysts , 2010 .

[16]  R. Schlögl,et al.  In situ Surface Characterization of the Intermetallic Compound PdGa – A Highly Selective Hydrogenation Catalyst , 2009 .

[17]  Di Wang,et al.  Pd/Ga2O3 methanol steam reforming catalysts: Part I. Morphology, composition and structural aspects , 2009 .

[18]  B. Gates,et al.  CO oxidation catalyzed by gold supported on MgO: Spectroscopic identification of carbonate-like species bonded to gold during catalyst deactivation , 2009 .

[19]  R. Schlögl,et al.  Understanding palladium hydrogenation catalysts: when the nature of the reactive molecule controls the nature of the catalyst active phase. , 2008, Angewandte Chemie.

[20]  Robert Schlögl,et al.  Palladium Gallium Intermetallic Compounds for the Selective Hydrogenation of Acetylene Part II: Surface Characterization and Catalytic Performance , 2008 .

[21]  R. Schlögl,et al.  Palladium–gallium intermetallic compounds for the selective hydrogenation of acetylene: Part I: Preparation and structural investigation under reaction conditions , 2008 .

[22]  G. Bond,et al.  Selective Hydrogenation of Ethyne in Ethene‐Rich Streams on Palladium Catalysts, Part 2: Steady‐State Kinetics and Effects of Palladium Particle Size, Carbon Monoxide, and Promoters , 2008 .

[23]  Thomas Bligaard,et al.  Identification of Non-Precious Metal Alloy Catalysts for Selective Hydrogenation of Acetylene , 2008, Science.

[24]  Axel Knop-Gericke,et al.  The Roles of Subsurface Carbon and Hydrogen in Palladium-Catalyzed Alkyne Hydrogenation , 2008, Science.

[25]  D. Tichit,et al.  LDH Nanocomposites with Different Guest Entities as Precursors of Supported Ni Catalysts , 2008 .

[26]  R. Schlögl,et al.  The mechanism of carbonate formation on Pd-Al2O3 catalysts. , 2008, Chemical communications.

[27]  M. Bäumer,et al.  Pd nanoparticles with highly defined structure on MgO as model catalysts : An FTIR study of the interaction with CO, O2, and H2 under ambient conditions , 2007 .

[28]  Tetsuya Shishido,et al.  Preparation of supported metal catalysts starting from hydrotalcites as the precursors and their improvements by adopting “memory effect” , 2007 .

[29]  R. Schlögl,et al.  Alkyne hydrogenation over Pd catalysts: A new paradigm , 2006 .

[30]  G. Bond,et al.  Selective Hydrogenation of Ethyne in Ethene‐Rich Streams on Palladium Catalysts. Part 1. Effect of Changes to the Catalyst During Reaction , 2006 .

[31]  David G. Evans,et al.  Layered Double Hydroxides , 2006 .

[32]  T. Hibino,et al.  Chapter 13.1 Layered Double Hydroxides , 2006 .

[33]  M. Bäumer,et al.  The application of infrared spectroscopy to probe the surface morphology of alumina-supported palladium catalysts. , 2005, The Journal of chemical physics.

[34]  M. Neurock,et al.  First-principles analysis of the effects of alloying Pd with Ag for the catalytic hydrogenation of acetylene-ethylene mixtures. , 2005, The journal of physical chemistry. B.

[35]  H. Freund,et al.  Surface reactivity of Pd nanoparticles supported on polycrystalline substrates as compared to thin film model catalysts: infrared study of CH3OH adsorption , 2004 .

[36]  G. Ghiotti,et al.  Pd/Mg(Al)O catalysts obtained from hydrotalcites: investigation of acid–base properties and nature of Pd phases , 2004 .

[37]  N. Iwasa,et al.  New Supported Pd and Pt Alloy Catalysts for Steam Reforming and Dehydrogenation of Methanol , 2003 .

[38]  J. Fierro,et al.  Gallium–Hydrogen Bond Formation on Gallium and Gallium–Palladium Silica-Supported Catalysts , 2002 .

[39]  S. Srivastava,et al.  Catalytic characterization of bi-functional catalysts derived from Pd-Mg-Al layered double hydroxides , 2002 .

[40]  C. L. Cruz,et al.  The reliability of vibrational spectroscopy as a means of identification of the structures of chemisorbed species on metal surfaces: the cases of CO, NO and C2 hydrocarbon surface species , 2001 .

[41]  B. Harbrecht,et al.  Phase equilibria in the palladium-rich part of the gallium–palladium system. The crystal structures of Ga3Pd7 and Ga1−xPd2+x , 2001 .

[42]  A. Baiker,et al.  Selectivity enhancement in heterogeneous catalysis induced by reaction modifiers , 2000 .

[43]  Vicente Rives,et al.  Layered double hydroxides with the hydrotalcite-type structure containing Cu2+, Ni2+ and Al3+ , 2000 .

[44]  W. Tysoe,et al.  The Hydrogenation of Acetylene Catalyzed by Palladium: Hydrogen Pressure Dependence , 1999 .

[45]  K. Chang,et al.  Effect of Ag‐promotion on Pd catalysts by XANES , 1998 .

[46]  A. D. Roy Lamellar Double Hydroxides , 1998 .

[47]  S. Tauster Strong metal-support interactions , 1986 .

[48]  R. Harlow,et al.  Formation of interstitial palladium-carbon phase by interaction of ethylene, acetylene, and carbon monoxide with palladium , 1985 .

[49]  S. C. Fung,et al.  Strong metal-support interactions. Group 8 noble metals supported on titanium dioxide , 1978 .

[50]  R. D. Shannon Revised effective ionic radii and systematic studies of interatomic distances in halides and chalcogenides , 1976 .

[51]  G. Bond,et al.  The selective hydrogenation of acetylene , 1958 .