Topic
Chemisorption
About: Chemisorption is a research topic. Over the lifetime, 16298 publications have been published within this topic receiving 554989 citations.
Papers published on a yearly basis
Papers
More filters
TL;DR: In this article, the adsorption of N2 on clean Fe(100) and Fe(111) single-crystal surfaces was studied in the temperature range 140-1000 K by means of Auger electron spectroscopy (AES), low-energy electron diffraction (LEED), ultraviolet photoelectron spectroscopic (UPS), thermal-desorption (TDS) and work-function measurements (Δφ).
349 citations
TL;DR: In this article, it was shown that small perturbations to the energy of the iron (III) 2p electrons can be attributed to changes in crystal structure and multiplet splitting and shake-up in the iron oxides contributes to iron 2p peak widths; the chemisorption of water has a marked effect upon the observed peak profiles; the oxygen 1s peaks due to oxide, hydroxyl, and adsorbed water have been characterised.
Abstract: X-Ray photoelectron spectroscopy has been used to study a series of iron oxides. It has been shown that iron metal has a different ionisation energy from a number of iron(III) oxides. Small perturbations to the energy of the iron (III) 2p electrons can be attributed to changes in crystal structure. Multiplet splitting and shake-up in the iron oxides contributes to iron 2p peak widths. The chemisorption of water has a marked effect upon the observed peak profiles; the oxygen 1s peaks due to oxide, hydroxyl, and adsorbed water have been characterised.
348 citations
TL;DR: In this paper, a study of the chemistry involved in preparation, pretreatment, and reduction of Ni Al 2 O 3 catalysts was carried out using hydrogen chemisorption, thermal gravimetric analysis, and chromatographic analysis.
347 citations
TL;DR: In this article, the H-graphite interaction is studied for the first time in the framework of density functional theory, and a coronene-like model of the 0001 graphite surface is considered.
347 citations
Book•
22 Jul 2005TL;DR: In this paper, the authors proposed a method for determining the presence of mass and heat transfer effects in a reaction in a single-site ad-orption setup using the Madon-Boudart method.
Abstract: Foreword Preface List of Symbols 1. Regular Symbols 2. Greek Symbols 3. Subscripts 1: Introduction 2: Definitions and Concepts 2.1 Stoichiometric Coefficients 2.2 Extent of Reaction 2.3 Rate of Reaction 2.4 Turnover Frequency or Specific Activity 2.5 Selectivity 2.6 Structure-Sensitive and Structure4nsensitive Reactions 2.7 Elementary Step and Rate Determining Step (RDS) 2.8 Reaction Pathway or Catalytic Cycle 2.9 Most Abundant Reaction Intermediate (MARI) 2.10 Chain Reactions 2.11 Reaction Rates in Reactors 2.12 Metal Dispersion (Fraction Exposed) 2.13 Meta1Support Interactions (MSI) References 3: Catalyst Characterization 3.1 Total (BET) Surface Area 3.2 Pore Volume and Pore Size Distribution 3.2.1 Hg Porosimetry Method 3.2.2 N2 Desorption Method 3.2.3 Overall Pore Size Distribution 3.3 Metal Surface Area, Crystallite Size, and Dispersion 3.3.1 Transmission Electron Microscopy (TEM) 3.3.2 X-Ray Techniques 3.3.2.1 Line Broadening of X-Ray Diffraction (XRD) Peaks 3.3.2.2 Extended X-Ray Absorption Fine Structure (EXAFS) 3.3.3 Magnetic Measurements 3.3.4 Chemisorption Methods 3.3.4.1 H2 Chemisorption 3.3.4.2 CO Chemisorption 3.3.4.3 02 Chemisorption 3.3.4.4 H2-02 Titration Techniques 3 3.5 Relationships Between Metal Dispersion, Surface Area, and Crystallite Size References Problems 4: Acquisition and Evaluation of Reaction Rate Data 4.1 Types of Reactors 4.1.1 Batch Reactor 4.1.2 Semi-Batch Reactor 4.1.3 Plug-Flow Reactor (PFR) 4.1.4 Continuous Flow Stirred-Tank Reactor (CSTR) 4.2 Heat and Mass Transfer Effects 4.2.1 Interphase (External) Gradients (Damkohler Number) 4.2.1.1 Isothermal Conditions 4.2.1.2 Nonisothermal Conditions 4.2.2 Intraphase (Internal) Gradients (Thiele Modulus) 4.2.1.1 Isothermal Conditions 4.2.2.2Nonisothermal Conditions 4.2.2.3 Determining an Intraphase (Internal) Effectiveness Factor from a Thiele Modulus 4.2.3 Intraphase Gradients (Weisz-Prater Criterion) 4.2.3.1 Gas-Phase or Vapor-Phase Reactions 4.2.3.2 Liquid-Phase Reactions 4.2.4 Other Criteria to Verify the Absence of Mass and Heat Transfer Limitations (The Madon-Boudart Method) 4.2.5 Summary of Tests for Mass and Heat Transfer Effects References Problems 5: Adsorption and Desorption Processes 5.1 Adsorption Rate 5.2 Desorption Rate 5.3 Adsorption Equilibrium on Uniform (Ideal) Surfaces-Langmuir Isotherms 5.3.1 Single-Site (Nondissociative) Adsorption 5.3.2 Dual-Site (Dissociative) Adsorption 5.3.3 Derivation of the Langmuir Isotherm by Other Approaches 5.3.4 Competitive Adsorption 5.4 Adsorption Equilibrium on Nonuniform (Nonideal) Surfaces 5.4.1 The Freundlich Isotherm 5.4.2 The Temkin Isotherm 5.5 Activated Adsorption References Problems 6: Kinetic Data Analysis and Evaluation of Model Parameters for Uniform (Ideal) Surfaces 6.1 Transition-State Theory (TST) or Absolute Rate Theory 6.2 The Steady-State Approximation (SSA) 6.3 Heats of Adsorption and Activation Barriers on Metal Surfaces: BOC-MP/UBI-QEP Method 6.3.1 Basic BOC-MP/UBI-QEP Assumptions 6.3.2 Heats of Atomic Chemisorption 6.3.3 Heats of Molecular Chemisorption 6.3.4 Activation Barriers for Dissociation and Recombination on Metal Surfaces 6.4 Use of a Rate Determining Step (RDS) and/or a Most Abundant Reaction Intermediate (MARl) 6.5 Evaluation of Parameter Consistency in Rate Expressions for Ideal Surfaces References Problems 7: Modeling Reactions on Uniform (Ideal) Surfaces 7.1 Reaction Models with a RDS Unimolecular Surface Reactions 7.2 Reaction Models with a RDS Bimolecular Surface Reactions 7.3 Reaction Models with a RDS Reactions between an Adsorbed Species and a Gas
346 citations