Dissertation > Excellent graduate degree dissertation topics show
Synthesis and Application of Graphene-Based Palladium Catalysts
Author: LiYingZhi
Tutor: LiuChangJun
School: Tianjin University
Course: Chemical processes
Keywords: CO oxidation catalyst graphene Palladium kinetic Densityfunctional theory
CLC: O643.36
Type: Master's thesis
Year: 2012
Downloads: 237
Quote: 0
Read: Download Dissertation
Abstract
|
Graphene has attracted an increasing attention as a zero bandgap, sp2-hybridizedcarbon material. Metal graphene composite is promising for many applications, suchas molecular electronics, sensors, supercapacitor, solar cell. It is of great significanceto synthesize the metal graphene composises with controllable size, shape andstructure. In addition, due to the random distribution of carbon-vacancy defect and thefunctional groups in chemical derived graphene, it is difficult to control the compositestructure. However, the metal ions can be adsorbed and intercalated into graphenesheets to form thermal stable composite materials, and the interaction can also beutilized to regulate the nucleation and crystal growth and prepare the structurecontrolled composites. Herein, several reduction methods are employed to synthesizehighly dispersed and structure controlled palladium nanoparticles (Pd NPs) on thegraphene sheet without any stabilizer and dispersant. And the Pd structure and sizeeffect towards CO oxidation activity and mechanism are also investigated.Pd-graphene catalysts have been prepared using the plasma reduction, hydrogenreduction and chemical reduction method. The density functional theory (DFT) studyand the catalyst characterization using Raman and XPS confirm that the oxygencontaining groups play an important role in stabilizing Pd clusters on graphene. Thefirst layer of the metal particle mainly presents as PdOx. The TEM, HRTEM and XRDresults demonstrated that highly dispersed Pd NPs are formed on the graphene sheets,and the Pd crystals are twin crystal, single crystal and polycrystal, respectively.Both the Pd structure and particle size have an obvious effect towards COoxidation activity, where the catalyst active center is Pd0. The graphene supported Pdcatalyst shows good catalytic activity and high stability for CO oxidation.The kinetic test and DFT studies indicate that CO oxidation over the graphenesupported Pd catalyst follows the Langmuir-Hinshelwood (L-H) mechanism, wherethe chemisorbed CO reacts with the chemisorbed oxygen. The rate determining step isthe O2adsorption dissociation, and the activation energy is the O2dissociation energy.
|
Related Dissertations
- Synthesis and Characterization on Semi-Aromatic Polyamides Containing Benzoxazole Units,O633.5
- Study on the Design and Biomechanical Behaviors of Individualized Artificial Knee Joint,R318.1
- Study on the Procees for the Preparation of Prohexadione and Its Analogs,TQ452
- Study on Using Sepiolite As Supported Catalysts in Selective Hydrogenation of Cinnamaldehyde to Cinnamyl Alcohol,O643.32
- The Preparation of Polyaniline-Metal Complex and the Study on Its Catalytical Property,O634
- Synthesis and Characterization of Monovalent, Divalent Imidazolium Ionic Liquids Containing Hydrocarbons,O621.3
- Indirect Imaging of Singlet Oxygen Generation from a Single Cell,Q2-3
- Pt -based catalysts of direct methanol fuel cells,TM911.4
- Synthesis and Study on Graphene and Co3O4/Graphene Composite about the Characteristics of Electrochemistry,O613.71
- The Study of Anode Catalyst Pd/C for Direct Formic Acid Fuel Cell,O643.36
- Study on the Synthesis of the Polypyrrole-Cobalt Oxides and Their Catalytic Behavior for the Electroreduction of H2O2,O643.32
- The Basicity of MO/ZrO2 Catalyst and Their Use in the Synthesis of 2-Ethyl-Hexyl Carbonate,O623.662
- Studies on Prediction Models for Fruit Decay and Shelf-Life of Postharvest Strawberry,TS255.4
- Application of Charcoal Loaded Catalyst for Treatment of Organic Pollutants,X703
- Controllable Synthesis of Carbon Nanotubes Supported Metall Nanocatalysts and the Study on Their Electrocatalysis,O643.36
- Synthesis of 1,4-Butynediol from HCHO and C2H2 Over CuO-Bi2O3/MgO-SiO2,TQ223.162
- Pyrohydrolysis of Corn Stover Catalyzed by Dilute Nitric Acid and Biological Acidification of Hydrolysate,X712
- Preparation of graphene Defects,O613.71
- Research on Fuel Gas Production from Catalytic Gasification of Municipal Solid Wastes,X799.3
- PtRh / Pt 5 / C Catalyst Preparation, Characterization and Electrocatalytic Oxidation of Ethanol,TM911.4
- Epoxidation of olefins with high activity cobalt zeolite catalysts,O643.32
CLC: > Mathematical sciences and chemical > Chemistry > Physical Chemistry ( theoretical chemistry ),chemical physics > Chemical kinetics,catalysis > Catalytic > Catalyst
© 2012 www.DissertationTopic.Net Mobile
|