Aryl Diazonium Salts: New Coupling Agents and Surafec Science Book

Preface XV

List of Contributors XVII

1.6.1 Chemical Structure 21

1.6.2 The Spatial Structure of the Layers 22

1.6.3 Compactness of the Layers 23

1.6.4 Swelling of the Layer 24

1.6.5 Electron Transfer through the Layers 24

1.6.6 The Formation Mechanism of Multilayers 25

1.7 Conclusion 27

References 27

2 Aryl–Surface Bonding: A Density Functional Theory (DFT) Simulation Approach 37
Nan Shao, Sheng Dai, and De-en Jiang

2.1 Introduction 37

2.2 Density Functional Theory 38

2.3 Bonding between Aryl and Various Substrates 38

2.3.1 On Graphite/Graphene 39

2.3.1.1 On the Basal Plane 39

2.3.1.2 On the Edges of Graphene 42

2.3.2 On Carbon Nanotubes 44

2.3.3 On Metal Surfaces 45

2.4 Summary and Outlook 48

Acknowledgments 49

References 50

3 Patterned Molecular Layers on Surfaces 53
Alison J. Downard, Andrew J. Gross, and Bradley M. Simons

3.1 Methods Based on Scanning Probe Lithography 53

3.1.1 AFM 54

3.1.2 SECM 54

3.1.3 Spotting 56

3.2 Methods Based on Soft Lithography 57

3.2.1 Printing 57

3.2.2 Molds 59

3.2.3 Nanosphere Lithography 59

3.3 Methods Based on Lithography 60

3.4 Methods Based on Surface-Directed Patterning 62

3.4.1 Modifi cation of Si Surfaces 63

3.4.2 Modifi ed Electrode Arrays 64

3.5 Summary and Conclusions 66

References 68

4 Analytical Methods for the Characterization of Aryl Layers 71
Karsten Hinrichs, Katy Roodenko, Jörg Rappich, Mohamed M. Chehimi, and Jean Pinson

4.1 Introduction 71

4.2 Scanning Probe Microscopies 71

4.3 UV–VIS Spectroscopy: Transmission, Reflection, and Ellipsometry 72

4.4 IR Spectroscopy 72

4.4.1 Transmission Spectroscopy 73

4.4.2 Refl ection Spectroscopy 74

4.4.3 Infrared Spectroscopic Ellipsometry (IRSE) 75

4.4.4 IRSE Surface Characterization 77

4.4.5 In Situ IR Spectroscopy: ATR and IRSE 79

4.5 Raman Spectroscopy and Surface-Enhanced Raman Scattering (SERS) 83

4.6 X-ray Photoelectron Spectroscopy (XPS) 84

4.7 X-ray Standing Waves (XSW) 91

4.8 Rutherford Backscattering 93

4.9 Time of Flight Secondary Ion Mass Spectroscopy 93

4.10 Electrochemistry 94

4.11 Contact Angle Measurements 96

4.12 Conclusion 96

References 98

5 Modification of Nano-objects by Aryl Diazonium Salts 103
Dao-Jun Guo and Fakhradin Mirkhalaf

5.1 Introduction 103

5.2 Electrochemical Modifi cation of Nano-objects by Reduction of Diazonium Salts 105

5.2.1 Surface Modifi cation of Carbon Nano-objects via Electrochemical Reduction of Aryl Diazonium Cations 105

5.2.2 Surface Modifi cation of Metal and Metal Oxide Nano-objects via Electrochemical Reduction of Aryl Diazonium Cations 111

5.3 Chemical Modification of Nano-objects by Reduction of Diazonium Salts 112

5.3.1 Surface Modifi cation of Carbon Nano-objects via Chemical Reduction of Aryl Diazonium Cations 112

5.3.2 Surface Modifi cation of Metal and Metal Oxide Nano-objects via Chemical Reduction of Aryl Diazonium Cations 116

5.4 Summary and Conclusions 119

Acknowledgments 120

References 120 Methods and Applications 125

Sarra Gam-Derouich, Samia Mahouche-Chergui, Hatem Ben Romdhane, and Mohamed M. Chehimi

6.1 Introduction 125

6.2 Methods for Grafting Coupling Agents from Aryl Diazonium Compounds 127

6.3 Grafting Macromolecules to Surfaces through Aryl Layers 130

6.3.1 Binding Macromolecules to Surfaces by a Grafting from Strategy 130

6.3.1.1 Surface-Initiated Atom Transfer Radical Polymerization (SI-ATRP) 130

6.3.1.2 Surface-Initiated Reversible Addition–Fragmentation Chain Transfer (SI-RAFT) 142

6.3.1.3 Surface-Initiated Photopolymerization 143

6.3.1.4 Alternative Methods 146

6.3.2 Attachment of Macromolecules through Grafting onto Strategies 147

6.3.2.1 Photochemical Attachment 147

6.3.2.2 Ring Opening 148

6.3.2.3 Acylation 149

6.3.2.4 Click Chemistry 149

6.3.2.5 Diazotation of Substrates and Macromolecules 150

6.4 Adhesion of Polymers to Surfaces through Aryl Layers 151

6.5 Conclusion 153

References 153

7 Grafting Polymer Films onto Material Surfaces: The One-Step Redox Processes 159
Guy Deniau, Serge Palacin, Alice Mesnage, and Lorraine Tessier

7.1 Cathodic Electrografting (CE) in an Organic Medium 160

7.1.1 Direct Cathodic Electrografting of Vinylic Polymers 160

7.1.2 Indirect Cathodic Electrografting 162

7.2 Surface Electroinitiated Emulsion Polymerization (SEEP) 164

7.2.1 Characterization of Poly(Butyl Methacrylate) Films 166

7.2.2 Determination of the Film Structure 167

7.2.3 Reduction of Protons and the Role of Hydrogen Radicals 169

7.2.4 Mechanism of SEEP 170

7.3 Chemical Grafting via Chemical Redox Activation (Graftfast™) 171

7.3.1 Process without Vinylic Monomer 172

7.3.2 Process with Vinylic Monomer 174

7.3.2.1 Type of Materials 174

7.3.2.2 Parameters Controlled in the Process 174

7.4 Summary and Conclusions 177

References 178

8 Electrografting of Conductive Oligomers and Polymers 181
Jean Christophe Lacroix, Jalal Ghilane, Luis Santos, Gaelle Trippe-Allard, Pascal Martin, and Hyacinthe Randriamahazaka

8.1 Introduction 181

8.2 Conjugated Oligomers and Polymers 181

8.3 Surface Grafting Based on Electroreduction of Diazonium Salts

184

8.4 Polyphenylene and Oligophenylene-Tethered Surface Prepared by the Diazonium Reduction of Aniline or 4-Substituted Aniline 187

8.5 n-Doping and Conductance Switching of Grafted Biphenyl, Terphenyl, Nitro-biphenyl and 4-Nitroazobenzene Mono- and Multilayers 187

8.6 p-Doping and Conductance Switching of Grafted Oligo-Phenylthiophene or Oligothiophene Mono- and Multilayers 190

8.7 p-Doping and Conductance Switching of Grafted Oligoaniline Mono- and Multilayers 192

8.8 Conclusion and Outlook 193

References 195

9 The Use of Aryl Diazonium Salts in the Fabrication of Biosensors and Chemical Sensors 197
J. Justin Gooding, Guozhen Liu, and Alicia L. Gui

9.1 Introduction 197

9.1.1 Sensors and Interfacial Design 197

9.1.2 Molecular Level Control over the Fabrication of Sensing Interfaces 198

9.2 The Important Features of Aryl Diazonium Salts with Regard to Sensing 200

9.3 Sensors and Biosensors Fabricated Using Aryl Diazonium Salts 201

9.3.1 Chemical Sensors – Sensors Fabricated via the Immobilization of Chemical Recognition Species 201

9.3.2 Biosensors 205

9.3.2.1 Enzyme Biosensors 206

9.3.2.2 Immunobiosensors 208

9.3.2.3 DNA-Based Biosensors 210

9.3.2.4 Cell-Based Biosensors 213

9.4 Conclusions 213

References 214

10 Diazonium Compounds in Molecular Electronics 219
Richard McCreery and Adam Johan Bergren

10.1 Introduction 219

10.2 Fabrication of Molecular Junctions Using Diazonium Reagents 222

10.2.1 Substrates for Diazonium-Derived Molecular Junctions 222

10.2.2 Surface Modifi cation Using Diazonium Chemistry 223

10.2.3 Application of Top Contacts 225

10.3 Electronic Performance of Diazonium-Derived Molecular Junctions 226

10.3.1 Surface Diffusion Mediated Deposition (SDMD) 227

10.3.2 Structural Control of Molecular Junction Behavior 230

10.3.3 Redox Reactions in Molecular Junctions 232

10.3.4 Microfabricated Molecular Devices Made with Diazonium Chemistry 233

10.4 Summary and Outlook 235

Acknowledgments 236

References 236

11 Electronic Properties of Si Surfaces Modified by Aryl Diazonium Compounds 241
Jörg Rappich, Xin Zhang, and Karsten Hinrichs

11.1 Introduction 241

11.2 Experimental Techniques to Characterize Electronic Properties of Si Surfaces in Solutions 242

11.2.1 In Situ Photoluminescence and Photo Voltage Measurements 242

11.2.2 In Situ PL and PV Measurements during Electrochemical Grafting 244

11.2.3 Reaction Scheme of the Electrochemical Grafting via Diazonium Ions 245

11.2.4 Change in IPL and UPV during Electrochemical Grafting onto Si Surfaces 246

11.2.5 Change in Band Bending and Work Function after Electrochemical Grafting onto Si Surfaces 248

11.2.6 pH Dependence and Enhanced Surface Passivation 249

11.3 Conclusion and Outlook 251

Acknowledgments 252

References 252

12 Non-Diazonium Organic and Organometallic Coupling Agents for Surface Modification 255
Fetah I. Podvorica

12.1 Amines 255

12.1.1 Characterization of the Grafted Layer 257

12.1.1.1 Electrochemical Methods 257

12.1.1.2 Surface Analysis Techniques 258

12.1.2 Chemical Grafting 259

12.1.3 Localized Electrografting 260

12.1.4 Grafting Mechanism 261

12.1.5 Applications 262

12.2 Arylhydrazines 264

12.3 Aryltriazenes 266

12.4 Alcohols 267

12.4.1 Observation and Characterization of the Film 268

12.4.2 Applications 269

12.5 Grignard Reagents 270

12.5.1 Characterization of the Layers 271

12.5.2 Grafting Mechanism 272

12.6 Onium Salts 272

12.6.1 Iodonium Salts 272

12.6.2 Sulfonium Salts 273

12.6.3 Ammonium Salts 273

12.7 Alkyl Halides 274

12.8 Conclusion 275

References 276

13 Various Electrochemical Strategies for Grafting Electronic Functional Molecules to Silicon 283
Dinesh K. Aswal, Shankar Prasad Koiry, and Shiv Kumar Gupta

13.1 Introduction 283

13.2 Architecture of Hybrid Devices 284

13.2.1 Molecular Dielectrics and Wires 285

13.2.2 Molecular Diodes 286

13.2.3 Resonant Tunnel Diodes 286

13.2.4 Molecular Transistors 286

13.3 Electrografting of Monolayers to Si 287

13.3.1 Essential Requirements 287

13.3.2 Experimental Process of Electrografting 287

13.4 Negative Differential Resistance Effect in a Monolayer Electrografted Using a Diazonium Complex 288

13.4.1 Electrografting of DHTT 288

13.4.2 NDR Effect in DHTT Monolayers 290

13.5 Dielectric Monolayers Electrografted Using Silanes 293

13.5.1 Mechanism of Electrografting 293

13.5.2 Electrical Characterization 294

13.6 Molecular Diodes Based on C60/Porphyrin-Derivative Bilayers 295

13.6.1 Fabrication Process 296

13.6.1.1 Electrografting of Acceptor C60 Layer on Si 296

13.6.1.2 Self-Assembly of Donor Porphyrin Derivative Layer on C60/Si 297

13.6.2 Rectifi cation Characteristics of D–A Bilayers 298

13.7 Memory Effect in TPP-C11 Monolayers Electrografted Using a C=C Linker 301

13.7.1 Electrografting of TPP-C11 Monolayer 301

13.7.2 Electrical Bistability and Memory Effect 303

13.8 Summary 305

References 305

14 Patents and Industrial Applications of Aryl Diazonium Salts and Other Coupling Agents 309
James A. Belmont, Christophe Bureau, Mohamed M. Chehimi, Sarra Gam-Derouich, and Jean Pinson

14.1 Introduction 309

14.2 Patents 309

14.2.1 The Surface Chemistry of Diazonium Salts 309

14.2.2 The Surface Chemistry of Other Coupling Agents 310

14.2.3 Post-Modifi cation of the Grafted Layers 310

14.2.4 Composite Materials 310

14.2.5 The Surface Modifi cation of Nano-objects 312

14.2.6 Microelectronics 312

14.2.7 Biomedical Applications 312

14.2.8 Sensors, Biosensors, Surfaces for Biological Applications 312

14.2.9 Energy Conversion 313

14.3 Industrial Applications 313

14.3.1 The Development of Modifi ed Carbon Blacks 313

14.3.2 Industrial Applications of the Electropolymerization of Vinylics: Alchimer and AlchiMedics 314

14.3.2.1 From Research to Development 314

14.3.2.2 Application of eG™ to Drug-Eluting Stents: AlchiMedics 315

14.3.2.3 Application of eG™ to Copper Interconnects: Alchimer 317

14.4 Conclusion 319

References 319

Index 323