Electro-Catalysis at Chemically Modified Solid Surfaces 16

This book documents Professor Jacques Simonet's contribution to building new electrode materials and their related catalytic reactions. Research includes synthesis of new alloys of palladium, discovery of new composite electrodes (including gold- and silver-graphene) and the creation of new materials through judicious cathodic or anodic doping. Additionally, studies demonstrate the malleability and reactivity of previously unused precious and semi-precious metals for the creation of 2D and 3D catalytic materials. Studies key to innovative research show how transition metals may reversibly cathodically insert small size electro-active molecules such as CO2 and O2, and be applied to methods of depollution brought by carbon and nitrogen oxides.Written for practical use, Simonet has provided both theory and tools needed for those aiming to recreate and develop his experiments in electrochemical catalysis and surface modifications. This full publication of research gives graduate and post-graduate students of chemistry, electrochemistry and catalysis an in-depth insight into key historical and modern developments in the field. Cover Half Title Catalytic Science Series Electro-Catalysis at Chemically Modified Solid Surfaces Copyright Preface About the Author Acknowledgments Contents 1. How to Modify Solid Electrodes for Generating New Interfacial Processes — Another Approach in Electro-Chemical Catalysis 1.1. Introduction 1.2. About Redox Catalyses 1.2.1. Homogeneous redox catalysis 1.2.2. Heterogeneous redox catalysis 1.2.3. Arenization of glassy carbon 1.3. Building and Reduction of Electrophilic Layers onto Carbons 1.4. Intrinsically Catalytic Electrodes 1.5. Triggering of Radical Chains via Electro-Chemical Activation 1.6. Modified Carbons as Electrode Materials 1.6.1. Some unusual reactions with carbons 1.6.2. Composite carbonaceous materials as multi-layer reactive systems 1.7. Specifically Modified Metallic Electrodes for Achieving Catalysis 1.8. Growing and Deposition of Ionophoric Species at Carbon and Metals by Anodic Means 1.9. When the Cathodic Doping of Metals (Platinum and Palladium) in Super-Dry Media Permits the Insertion of Organic Acceptors into Metals 1.10. Sequestration of Carbon Dioxide Gas into Transition Metal Bulks References 2. Palladized Silver as Cathode Material: Catalytic One-Electron Scission of Carbon–Halogen Bonds 2.1. Introduction 2.2. Interest for Highly Catalytic Solid Electrodes 2.3. Chemical Doping of Silver by Palladium 2.4. Structural Characterization of the Ag–Pd Interface 2.5. Palladized Silver Interfaces for a Catalytic Reactivity of Primary Alkyl Iodides 2.6. Reduction of Alkyl Bromides 2.7. Supported Layers of Silver and Silver–Palladium onto Solid Conductors 2.8. Macro Ag–Pd Cathodes 2.9. Conclusion References 3. A Disordered Copper–Palladium Alloy Electrode: Catalytic Scission 3.1. Introduction 3.2. How to Generate a Palladized Copper Alloy at Room Temperature 3.2.1. Texture and structure analyses 3.2.2. The palladized copper interface 3.3. Cathodic Cleavages of Carbon–Halogen Bonds at Cu–Pd Electrodes 3.3.1. Scission of primary alkyl iodides (RIs) 3.3.2. Cu–Pd electrodes for the scission of C–Br bonds 3.4. Capping Carbon Surfaces by Cu–Pd Layers 3.5. Comments and Conclusion References 4. Electro-Catalysis by Subnanomolar Metal Layers: Immobilization of Redox Marked Radicals onto Carbon 4.1. Introduction 4.2. Primary Alkyl Iodides Electro-Chemically Reduced at GC Doped with Palladium 4.2.1. One-electron deposition from ω -iodoalkyferrocenes by means of palladium catalysis 4.2.2. Catalysis involving other transition metals 4.2.3. 1-Iododecylferrocene: Generation of alkylferrocene SAM 4.2.4. Generation of three-dimensional (3D) electrodes made of GC, graphene, and transition metal microparticles 4.3. Merging and Growing of SAMs from GC: Concept of Self-Elaborated 3D Interfaces 4.4. Characterization of Produced Alkylferrocene Layers References 5. Electro-Chemical Generation of Silver Nanoparticles: Catalytic Reactions at Solid Conductor Interfaces 5.1. Introduction 5.2. Experimental 5.2.1. Chemical doping of silver by palladium 5.2.2. Electro-chemical procedure: Solvents, electrolytes, and electrodes 5.2.3. Coulometries and electrolyses 5.3. Methodology 5.4. Silvering Processes 5.4.1. Voltammetries 5.4.2. Metalizing procedures 5.5. Structural Evidence of the Deposit: A Layer made of Pure Silver Nanoparticles 5.6. Building of New Electro-Catalytic Surfaces 5.7. Concluding Remarks References 6. The Carbon–Bromine Bond Scission: Activation and Immobilization of Free Radicals at Solid Surfaces 6.1. Introduction 6.2. Immobilization of Allyl Radical 6.3. Generation of Propargyl Radical: Acethylenization of Solid Surfaces 6.4. One-Electron Cleavage of Benzylic Bromides at Palladized Substrates 6.5. 9-Fluorenyl Radical 6.5.1. Generation 6.5.2. Fluorenation of solid surfaces References 7. Cathodic Reduction of Aryl Halides in Organic Carbonates for Achieving Aryl–Aryl Couplings 7.1. Introduction 7.2. Ar–Ar Linkage Generated by Electro-Chemistry 7.2.1. Experimental 7.2.2. Cathodic generation of Ar–Ar bonds: Conditions and limitations 7.3. Aryl Bromides and their Reactivity at Palladium Polarized Interfaces References 8. Large Immobilization of Organic Bielectrophilic Species at Carbon Surfaces 8.1. Introduction 8.2. Indirect Grafting of Ferrocene by Means of Diiodoalkanes at Charged Carbons 8.2.1. Experimental section 8.2.2. Reduction of α,ω-diiodoalkanes 8.2.3. Cathodic behavior of bis-(ω-iodoalkyl)ferrocenes 8.3. Remarks about the Incorporation of Redox Moieties inside Hydrophobic Polymeric Layers at Solid Surfaces 8.4. Electro-Chemical Attachment of Graphene at GC Surfaces via Di-haloalkanes References 9. 1,3-Dibromopropane: Electro-Catalytic Reactivity in the Presence of Transition Metals — A Source of Nanoparticles 9.1. Introduction 9.2. Methodology 9.3. Formation of NPs via DB3 9.4. Analytical Evidence for a Deposition of NPs at Carbon Electrodes 9.5. Copper: A Remarkable Cathode Material for Reduction of a,w-dibromoalkanes 9.6. Reactivity of DB3 at Copper Surfaces 9.7. Some Concluding Remarks References 10. Electro-Chemical Doping of Glassy Carbon by Deposition of Graphene Layers 10.1. Introduction 10.2. Exfoliation Procedure Applied to GC-Graphite Surfaces 10.2.1. An analytical evidence for the presence of graphite nanoinclusions in GC 10.2.2. Exfoliation processes and cathodic charge by insertion of several TAAX at GC-graphene materials 10.3. Reactivity and Modification of Carbon-Graphene Interfaces 10.3.1. Supported charged graphene layer as an efficient polynucleophile 10.3.2. Specific surface modifications induced by deposited charged graphene 10.3.3. Addition of free radicals onto the GC-graphene layer 10.4. Conclusion References 11. Electro-Chemical Carboxylation of Carbons 11.1. Introduction 11.2. Technical Methods Applied to Carbon Carboxylation 11.3. On the Cathodic Reactivity of Carbons 11.4. Electro-Generation of GC Polycarboxylates 11.5. Electro-Activity of Graphite (HOPG, Natural Graphite) 11.5.1. HOPG 11.5.2. Procedure for a carboxylation of natural graphite 11.5.3. The extent of carboxylation from analytical methods 11.6. Cathodic Carboxylation of Graphenes: A New Versatile Material 11.6.1. Introduction 11.6.2. GC electrode modified with graphene 11.6.3. Comments on experimental conditions 11.6.4. On the carboxylation of deposited graphene 11.7. Large-Scale Carboxylation of Graphene 11.7.1. Operating mode 11.7.2. Experimental considerations 11.7.3. What is the average level of grafting by the proposed procedure? 11.8. Conclusion References 12. Cathodic Immobilization of Functionalized Alkyl Chains at Polarized Glassy Carbon 12.1. Introduction 12.2. What is the Mechanism of the Immobilization of Alkyl Halides at Carbon Cathodes? 12.3. Results 12.3.1. Reduction of alkyl iodides and bromides 12.3.2. Functionalization of GC 12.3.3. Vinylation of carbon surfaces 12.3.4. Immobilization of alkanoid acid chains at carbon 12.3.5. An efficient alkyl-ferrocenyl capping of polarized GC 12.3.6. About the immobilization of tetrathiafulvalenes References 13. Grafting at Solid Surfaces via Trimethylsilyl Derivatives 13.1. An Overview 13.2. Oxidation of Allyltrimethylsilane (ATMS) at Carbon Anodes 13.3. Benzyltrimethylsilane (BTMS): Oxidation at Carbon Anodes 13.4. Oxidation of Phenyltrimethylsilane at GC Electrodes 13.5. TMS as a Vector for the Immobilization of RX at Solid Surfaces 13.5.1. Grafting of alkyl halides at carbons 13.5.2. Scission of organo-trimethylsilanes at gold and platinum 13.5.3. The versatile use of TMS–CH2–I under cathodic or anodic electron transfer 13.6. Conclusion References 14. Cathodic Corrosion Induced by Free Alkyl Radicals at Silvered Carbon Substrates 14.1. Introduction 14.2. Generation of Free Alkyl Radicals at GC Surfaces 14.2.1. Methodology 14.2.2. Evidence for an alkyl radical reactivity toward GC surfaces 14.2.3. Preliminary step: A radical grafting at GC? 14.3. Polarized Graphite as a Trapping Material for Alkyl Radicals References 15. Silver–Graphene and Gold–Graphene Electrodes: Two New Catalytic Materials 15.1. Introduction 15.2. Ag–Graphene Surfaces 15.2.1. Electro-chemical properties of Ag–graphene layers 15.2.2. Modification of the graphene layer by addition of in situ generated free radicals 15.3. Electro-Chemical Exfoliation of Natural Graphite at a Gold Substrate 15.3.1. How to prepare Au–graphene working electrodes 15.3.2. Au–graphene interface: Formation and structure 15.3.3. Au–graphene interface as a spin-trap References 16. Anodic Coupling of Aromatic Ethers: The Synthesis of Ionophoric Redox Materials Deposited at Solid Surfaces 16.1. Introduction 16.2. Anodic Trimerization of Orthodimethoxy Benzenes 16.2.1. Oxidation of orthodialkoxybenzenzes 16.2.2. A first approach toward the anodic synthesis of ionophores 16.3. The Concept of Ionophoric Polymers Based on Anodic Oxidation of Aromatic Ethers 16.3.1. Voltammetries and electro-chemical conversion of dibenzocrown ethers into ionophoric polymeric materials 16.3.2. About complexing properties of poly-dibenzo crown ethers 16.4. Generation of Poly-Electrides References 17. Attachment of Pyridines at Electrode Surfaces 17.1. Introduction 17.2. Experimental Conditions 17.3. First Evidence for the Immobilization of 4-(7-iodoheptyl)pyridine 17.4. Reactivity of Bromo- and Chloroalkyl Pyridines as Solid Surfaces 17.5. Introduction to a General Mode of Bipyridine Graftings 17.6. About Complexation of Transition Metal Cations by Bipyridine Layers 17.7. Conclusion References 18. The Insertion of Electrolytes into Platinum and Palladium under Cathodic Super-Dry Conditions 18.1. Introduction 18.2. Experimental Conditions Required for a Cathodic Charge of Platinum and Palladium 18.3. Platinum Charge in Super-Dry Conditions 18.3.1. Behavior in the contact of alkali metal salts 18.3.2. Charge process in the presence of TAAX salts 18.3.3. Evidencing smooth platinum surface changes by SEM 18.3.4. Following of the platinum charge–discharge in real time: Use of in situ EC–AFM 18.3.5. Modified platinum phases as reducing reagents 18.4. Cathodic Charge of Palladium in Super-Dry Media 18.5. Concluding Perspectives References 19. The Electro-Chemical Insertion of π-Acceptors in Platinum and Palladium: Reactive Organo-Metallic Phases 19.1. Introductory Concept 19.2. Reversible Electrical Charge of Palladium in the Presence of Different Salts in Super-Dry Electrolytes 19.3. Charge–Discharge of Palladium–Graphene Layers 19.4. Super-Oxide as a Donor toward Charged Palladium and Platinum 19.5. Additional Comments and Concluding Remarks References 20. Cathodic Carboxylation of Metals in Thick {M-CO2}n Layers: Electro-Chemical Sequestration of CO2 20.1. Introduction 20.2. Reactivity of Carbon Dioxide at a Negatively Polarized Gold Electrode 20.2.1. Comments on electro-chemically driven insertion/desorption of CO2 20.2.2. Additional remarks on the reversible sequestration of CO2 by gold 20.3. Carboxylation of Silver 20.4. Carboxylation of Palladium, Platinum and Rhodium 20.4.1. Palladium 20.4.2. Platinum 20.4.3. Rhodium 20.5. Carboxylation of Copper 20.6. Conclusive Remarks About the Reductive Insertion of Small Electro-active Molecules into Transition Metals References Index Cover back