Surface Science Letters Ethane Hydrogenolysis over Single Crystals of Nickel: Direct Detection of Structure Sensitivity *
نویسنده
چکیده
Single crystal catalysts have been used to investigate ethane hydrogenolysis. The apparatus used in these studies allows for catalyst preparation and surface characterization in ultrahigh vacuum (UHV) with an in vacua transfer to a second UHV chamber designed for high pressure kinetic studies. Kinetic measurements on single crystals of nickel show the hydrogenolysis of ethane to be “structure sensitive”. Absolute rate and activation energy differences are observed over different facets of nickel. The (100) surface is observed to be significantly more active for this reaction than the (111) surface.
منابع مشابه
Dissociative Adsorption and Hydrogenolysis of Ethane over Clean and Ni-Covered
The hydrogenolysis of ethane has been investigated on clean and Ni-covered Pt( 1 1 1) at reactant partial pressures between 0.5 and 4 Torr of ethane and between 80 and 270 Torr of hydrogen and for surface temperatures from 550 to 640 K. On clean Pt( 1 1 1) the hydrogenolysis reaction proceeds with an activation energy of 36.6 kcal/mol and reaction orders in C2H6 and H2 pressures of 1 and -1.8, ...
متن کاملStructural and Catalytic Properties of Model Supported Nickel Catalysts
published in Aduonce ACS Abstracts, January 1, 1994. 0022-36S4/94/2098-124S%04.S0/0 nation at present. Martini2 and Goodmani3 have suggested that the activity of different crystal planes toward hydrogenolysis is responsible for the observed variations in activity with metal particle size. Single-crystal surface science studies have shown these structure-sensitive reactions to proceed more rapid...
متن کاملChemical Modification of Chemisorptive and Catalytic Properties of Nickel
Several reactions representing important categories of catalytic systems have been studied on chemically modified single crystal surfaces. These reactions are methanation of CO and CO:. hydrogenolysis of ethane. hydrogenation of ethylene. and q&propane ring-opening and hydrogenolysis. Poisoning of the above reactions by ordered. suhmonolayer coverages of sulfur shou large nonlinear effects for ...
متن کاملDetection of Polymer Brushes developed via Single Crystal Growth
Single crystals consisting various surface morphologies and epitaxial structures were applied to investigate the effect of other phase regions in the vicinity of a given tethered chains-covered area having a certain molecular weight of amorphous brushes. The designed experiments demonstrated that regardless of the type of surface morphology (patterned and especial mixed-brushes, homo and co...
متن کاملHigh-surface-area catalyst design: Synthesis, characterization, and reaction studies of platinum nanoparticles in mesoporous SBA-15 silica.
Platinum nanoparticles in the size range of 1.7-7.1 nm were produced by alcohol reduction methods. A polymer (poly(vinylpyrrolidone), PVP) was used to stabilize the particles by capping them in aqueous solution. The particles were characterized by X-ray diffraction (XRD) and transmission electron microscopy (TEM). TEM investigations demonstrate that the particles have a narrow size distribution...
متن کامل