Electrochromism and electrochromic devices

Half-title......Page 3
Title......Page 5
Copyright......Page 6
Contents......Page 7
Preface......Page 11
References......Page 13
Acknowledgements......Page 14
Symbols and units......Page 16
Abbreviations and acronyms......Page 19
1.1 Electrode reactions and colour: electrochromism......Page 25
1.2 Non-redox electrochromism......Page 27
1.3 Previous reviews of electrochromism and electrochromic work......Page 30
1.4.1 Electrochrome type......Page 31
1.4.2 Contrast ratio CR......Page 33
1.4.3 Response time τ......Page 34
1.4.4 Write–erase efficiency......Page 35
1.4.5 Cycle life......Page 36
1.4.6 Power consumption......Page 37
1.4.7 Coloration efficiency η......Page 39
1.4.8 Primary and secondary electrochromism......Page 40
1.5 Multiple-colour systems: electropolychromism......Page 41
References......Page 42
2.3 Prussian blue evocation in historic redox-coloration processes......Page 49
2.4 Twentieth century: developments up to 1980......Page 51
References......Page 54
3.1 Introduction......Page 57
3.2.1 A cell with dissolved ions as reactants: the Gibbs energy and electromotive force......Page 58
3.2.3 Electrode potentials defined and illustrated......Page 59
3.2.4 A cell with metal electrodes in contact with ions of those metals......Page 61
3.2.5 The cell emf and the electrode potentials: the hydrogen scale......Page 63
3.2.6 Electrochromic electrodes......Page 64
3.3 Rates of charge and mass transport through a cell: overpotentials......Page 65
3.3.1 Mass transport mechanisms......Page 67
3.3.3 Diffusion......Page 68
Faradaic and non-faradaic currents......Page 69
3.4.1 Butler–Volmer kinetics of electrode reactions......Page 70
3.4.2 Cyclic voltammetry......Page 72
3.4.4 Ellipsometry......Page 74
References......Page 75
4.1 Amount of colour formed: extrinsic colour......Page 76
4.2 The electrochromic memory effect......Page 77
4.3 Intrinsic colour: coloration efficiency η......Page 78
4.3.1 Intrinsic colour: composite coloration efficiency (CCE)......Page 81
4.4 Optical charge transfer (CT)......Page 84
4.5.1 A brief synopsis of colorimetric theory......Page 86
References......Page 95
5.1 Kinetic considerations for type-I and type-II electrochromes: transport of electrochrome through liquid solutions......Page 99
5.3 Kinetic considerations for bleaching type-II electrochromes and bleaching and coloration of type-III electrochromes: transport of counter ions through solid electrochromes......Page 103
5.3.1 Kinetic background: preliminary assumptions......Page 105
5.3.2 Kinetic complications......Page 110
Model of Faughnan and Crandall: potentiostatic coloration......Page 115
Model of Green: galvanostatic coloration......Page 120
The model of Ingram, Duffy and Monk: an electronic percolation threshold......Page 123
Model of Bohnke: reduction of WV via neutral inserted species......Page 125
Recent developments: intervalence between WVI and WIV......Page 126
Additional experimental results......Page 127
Model of Faughnan and Crandall: potentiostatic bleaching......Page 129
Model of Green: potentiostatic bleaching......Page 132
Additional experimental evidence for concentration gradients......Page 133
Discussion – coloration and bleaching......Page 134
References......Page 139
6.1 Introduction to metal-oxide electrochromes......Page 149
6.1.2 Stability and durability of oxide electrochromes......Page 152
6.1.3 The preparation of thin-film oxide electrochromes......Page 154
Chemical vapour deposition (CVD)......Page 155
Electrodeposition......Page 156
Sol-gel techniques......Page 158
Other methods: sputtering in vacuo......Page 160
6.1.4 Electrochemistry in electrochromic films of metal oxides......Page 162
Selected biblography......Page 163
Preparation of tungsten oxide electrochromes......Page 164
Redox properties of WO3 electrochromes......Page 166
Optical properties of tungsten oxide electrochromes......Page 168
Devices containing tungsten trioxide electrochrome......Page 173
Preparation of molybdenum oxide electrochromes......Page 175
Redox chemistry of molybdenum oxide electrochromes......Page 176
Optical properties of molybdenum oxide electrochromes......Page 177
Devices containing molybdenum oxide electrochromes......Page 178
Preparation of iridium oxide electrochromes......Page 179
The redox chemistry of iridium oxide electrochromes......Page 181
Optical properties of iridium oxide electrochromes......Page 182
6.2.4 Nickel oxide......Page 183
Preparation of nickel oxide electrochromes......Page 184
Redox electrochemistry......Page 185
Optical properties of nickel oxide electrochromes......Page 187
Electrochromic devices containing nickel oxide electrochromes......Page 188
6.3.1 Introduction......Page 189
Cerium oxide......Page 190
Cobalt oxide......Page 191
Copper oxide......Page 194
Iron oxide......Page 196
Manganese oxide......Page 199
Niobium oxide......Page 200
Praseodymium oxide......Page 203
Tantalum oxide......Page 205
Tin oxide......Page 207
Titanium oxide......Page 208
Vanadium oxide......Page 209
6.4.1 Introduction......Page 214
Tungsten oxide as electrochromic host......Page 215
Cerium oxide as electrochromic host......Page 217
Cobalt oxide as electrochromic host......Page 219
Indium oxide as an electrochromic host......Page 220
Iron oxide as electrochromic host......Page 222
Molybdenum oxide as electrochromic host......Page 223
Niobium oxide as electrochromic host......Page 224
Titanium oxide as electrochromic host......Page 225
Vanadium oxide as electrochromic host......Page 226
Ternary and higher oxides......Page 227
6.4.3 Electrochromic oxides incorporating precious metals......Page 228
6.4.4 Metal oxyfluorides......Page 229
References......Page 230
7.1 Redox coloration and the underlying electronic transitions......Page 277
7.2.1 Polypyridyl complexes in solution......Page 278
7.2.2 Reductive electropolymerisation of polypyridyl complexes......Page 279
7.2.3 Oxidative electropolymerisation of polypyridyl complexes......Page 280
7.2.4 Spatial electrochromism of polymeric polypyridyl complexes......Page 281
7.3.1 Introduction to metal phthalocyanines and porphyrins......Page 282
7.3.2 Sublimed bis(phthalocyaninato)lutetium(III) films......Page 283
7.3.3 Other metal phthalocyanines......Page 284
7.3.4 Electrochemical routes to metallophthalocyanine electrochromic films......Page 285
7.3.5 Langmuir–Blodgett metallophthalocyanine electrochromic films......Page 286
7.3.6 Species related to metallophthalocyanines......Page 287
7.3.7 Electrochromic properties of porphyrins......Page 288
7.4.1 Significance of the near-infrared region......Page 289
7.4.2 Planar dithiolene complexes of Ni, Pd and Pt......Page 290
7.4.3 Mixed-valence dinuclear complexes of ruthenium......Page 291
7.4.4 Tris(pyrazolyl)borato-molybdenum complexes......Page 293
7.4.5 Ruthenium and osmium dioxolene complexes......Page 294
References......Page 298
8.1 Prussian blue systems: history and bulk properties......Page 306
8.2 Preparation of Prussian blue thin films......Page 307
8.3 Electrochemistry, in situ spectroscopy and characterisation of Prussian blue thin films......Page 309
8.4 Prussian blue electrochromic devices......Page 313
8.5 Prussian blue analogues......Page 315
8.5.2 Vanadium hexacyanoferrate......Page 316
8.5.3 Nickel hexacyanoferrate......Page 317
8.5.5 Palladium hexacyanoferrate......Page 318
8.5.7 Miscellaneous Prussian blue analogues......Page 319
References......Page 320
9.1 Fullerene-based electrochromes......Page 327
9.2 Other carbon-based electrochromes......Page 328
Bismuth......Page 329
Lead......Page 330
9.4 Reflecting metal hydrides......Page 331
References......Page 333
10.1.2 Types of electroactive conducting polymers......Page 336
10.1.3 Mechanism of oxidative polymerisation of resonance-stabilised aromatic molecules......Page 337
10.1.4 Conductivity and optical properties......Page 338
10.2.1 Introduction to poly(thiophene)s......Page 342
10.2.2 Poly(thiophene)s derived from substituted thiophenes and oligothiophenes......Page 344
10.2.3 Poly(thiophene)s derived from 3,4-(ethylenedioxy)thiophenes......Page 345
10.3 Poly(pyrrole)s and dioxypyrroles as electrochromes......Page 351
10.4 Poly(aniline)s as electrochromes......Page 352
10.5.2 All-polymer ECDs......Page 355
10.6.1 Novel routes to castable poly(aniline) films......Page 356
10.7 ECDs using both electroactive conducting polymers and inorganic electrochromes......Page 357
10.8 Conclusions and outlook......Page 358
References......Page 359
11 Introduction......Page 365
11.2 Bipyridilium redox chemistry......Page 366
11.3.1 Electrodes derivatised with viologens for ECD inclusion......Page 370
11.3.3 Soluble-to-insoluble viologen electrochromes for ECD inclusion......Page 372
11.3.4 Applications of bipyridilium systems in electrochromic devices......Page 373
11.3.5 The effect of the bipm N substituents......Page 375
11.3.6 The effect of the counter anion......Page 376
11.3.7 The kinetics and mechanism of viologen electrocoloration......Page 378
11.3.8 Micellar species......Page 379
11.3.9 The write–erase efficiency......Page 380
11.3.10 Attempts to improve the write–erase efficiency......Page 383
11.4.1 Displays based on viologens adsorbed on nanostructured titania......Page 384
11.4.4 Viologens incorporated within paper......Page 389
References......Page 390
12.1.1 Aromatic amine electrochromes......Page 398
12.1.3 Cyanine electrochromes......Page 400
12.1.4 Methoxybiphenyl electrochromes......Page 403
12.1.5 Quinone electrochromes......Page 405
12.1.6 Thiazine electrochromes......Page 409
12.2.1 Pyrazoline electrochromes......Page 411
12.2.2 Tetracyanoquinodimethane (TCNQ) electrochromes......Page 412
12.2.3 Tetrathiafulvalene (TTF) electrochromes......Page 413
References......Page 415
13.2 Reflective electrochromic devices: electrochromic car mirrors......Page 419
13.3 Buildings......Page 421
13.3.2 Aircraft – the first ubiquitous ECD window application: Gentex and Boeing......Page 424
13.4 Electrochromic displays for displaying images and data......Page 425
13.5 ECD light modulators and shutters in message-laser applications......Page 428
13.6 Electrochromic paper......Page 429
13.7 Electrochromes applied in quasi-electrochromic or non-electrochromic processes: sensors and analysis......Page 430
13.8 Miscellaneous electrochromic applications......Page 431
13.9 Combinatorial monitoring of multiples of varied electrode materials......Page 433
References......Page 434
14.1 Fundamentals of ECD construction......Page 441
14.2 Electrolyte layers for ECDs......Page 443
Polyelectrolytes......Page 444
Polymer electrolytes......Page 445
14.3.1 Transparent conductors......Page 446
14.3.2 Opaque and metallic conductors......Page 447
14.4 Device encapsulation......Page 448
References......Page 449
15.2 Direction of beam......Page 457
15.3.2 Photoconductive layers......Page 458
15.3.3 Photovoltaic materials......Page 461
15.4 Photochromic-electrochromic systems......Page 462
References......Page 464
16.1 Introduction......Page 467
16.2 Durability of transparent electrodes......Page 468
16.4 Enhancing the durability of electrochrome layers......Page 469
16.5 Durability of electrochromic devices after assembly......Page 470
References......Page 473
Index......Page 476