Preface ix
Acknowledgments xi
1 Introduction 1
1.1 Principles of Fuel Cells 1
1.2 Types of Fuel Cells 3
1.2.1 AFC 3
1.2.2 PAFC 6
1.2.3 MCFC 7
1.2.4 SOFC 8
1.2.5 PEMFC 11
1.2.6 DMFC 12
1.3 Applications 14
1.3.1 Stationary Power 15
1.3.2 Propulsion of Vehicles 15
1.3.3 Portable Applications 17
1.4 Needs of Fundamental Materials for PEM Fuel Cells 17
1.4.1 Membranes 17
1.4.2 Electrodes 18
1.4.3 Polymeric Materials as Components of Fuel Cell Catalytic System 20
1.4.4 Bipolar Plates 21
1.5 Membranes for PEM Fuel Cells 22
1.5.1 Proton Exchange Membranes 22
1.5.2 PEMs for DMFCs 29
1.5.3 Anion Exchange Membranes (AEMs) 34
1.5.4 Organic–Inorganic Composites 35
1.6 Testing of PEMs 36
References 36
2 Fluoropolymers for Proton Exchange Membranes 50
2.1 Introduction 50
2.2 Perfluorosulfonic Acid Resins 51
2.2.1 PFSA Polymers with Long Side Chains 53
2.2.2 PFSA Polymers with Short Side Chains 55
2.2.3 Sulfonimide Membranes 58
2.3 Partially Fluorinated Polymers 59
2.3.1 Partially Fluorinated Aromatic Polymers 59
2.3.2 Partially Fluorinated Graft Copolymers 67
2.4 Durability of Fluoropolymers for Proton Exchange Membranes 75
2.5 Composite Membranes Based on Fluoropolymers 82
2.5.1 Reinforcement by a Polymer 83
2.5.2 Organic–Inorganic Composite Membranes 83
2.5.3 Nafion®/Sulfonated Polymers 85
2.5.4 Multilayer Membranes 85
2.5.5 Semi-IPN Membranes 86
References 87
3 Nonfluorinated Polymers for Proton Exchange Membranes 102
3.1 Introduction 102
3.2 Sulfonated Polyimides 103
3.2.1 Synthesis of Sulfonated Polyimides 104
3.2.2 Structure and Properties of Sulfonated Polyimide 116
3.2.3 Modification of Sulfonated Polyimides 127
3.2.4 Fuel Cell Performance and Stability of sPI Membranes 136
3.3 Sulfonated Poly(ether ether ketone) 141
3.3.1 Synthesis of sPEEK 142
3.3.2 Structure and Properties 146
3.3.3 Modification of sPEEK Membranes 153
3.4 Sulfonated Polysulfone and Poly(ether sulfone) 160
3.4.1 Polysulfones and Poly(ether sulfone) 160
3.4.2 Sulfonation and Phosphonation of Polysulfones and Poly(ether sulfone)s 162
3.4.3 Poly(arylene thioether sulfone)s 180
3.5 Sulfonated Polyphosphazenes 181
3.5.1 Synthesis of Sulfonated Polyphosphazenes 184
3.5.2 Phenylphosphonic Acid-Functionalized Polyphosphazenes 187
3.5.3 Polyphosphazenes with Sulfonimide Side Groups 188
3.5.4 Modification of Sulfonated Polyphosphazenes 190
3.5.5 Polyphosphazene Membranes for PEMFCs 192
3.5.6 Polyphosphazene Membranes for DMFCs 193
3.6 Sulfonated Polybenzimidazole 194
3.7 Sulfonated Poly(phenylene oxide) 198
3.7.1 Sulfonated PPO for PEMs 198
3.7.2 Modification of sPPO 202
3.7.3 Fuel Cell Performances of sPPO Membranes 210
References 212
4 Anhydrous Proton-Conducting Polymers for High-Temperature PEMFCs 241
4.1 Introduction 241
4.2 Phosphoric Acid-Impregnated Polybenzimidazole Membranes 242
4.2.1 Synthesis of PBIs 243
4.2.2 Membrane Fabrication of PBIs 256
4.2.3 Structure and Properties of PBIs 259
4.2.4 Modification of PBIs 268
4.2.5 Composite Membranes of PBIs 271
4.2.6 Fuel Cell Technologies 272
References 276
5 Anion Exchange Membranes for Alkaline Fuel Cells 293
5.1 Introduction 293
5.2 Anion Exchange Membranes for Alkaline Fuel Cells 296
5.2.1 Heterogeneous Membranes 296
5.2.2 Interpenetrating Polymer Network 303
5.2.3 Homogeneous Membranes 304
5.3 Structure and Properties of AEMs 329
5.3.1 General Properties of AEMs 329
5.3.2 Properties of the Ionic Groups 331
5.3.3 Transport Mechanisms in AEMs 332
5.3.4 Stability of Alkaline AEMs 335
5.3.5 Examples of Chemical Stability of Ammonium Groups Toward OH- Attack 338
5.4 Application of AEMs 340
References 345
6 Polymers for New Types of Fuel Cells 360
6.1 Direct Liquid-Feed Fuel Cells 360
6.1.1 Introduction 360
6.1.2 Direct Liquid-Feed Fuels 361
6.1.3 Carbon-Free Fuels 369
6.2 Microbial Fuel Cells 373
6.2.1 Introduction 373
6.2.2 Materials of Construction 377
6.2.3 Outlook and Application of MFCs 379
6.3 Microfuel Cells 380
6.3.1 Introduction 380
6.3.2 Different Types of Microfuel Cells 382
6.3.3 Commercial Developments of Microfuel Cells 392
References 395
Index 407
