Nitrogen bridged polyphenylene based materials for electronic applications [Elektronische Ressource] / Ashok Kumar Mishra

Mishra

Informations

• Publié par: johannes_gutenberg-universitat_mainz
• Publié le: 01 janvier 2007
• Nombre de lectures: 68
• Langue: English
• Poids de l'ouvrage: 13 Mo

Extrait

Nitrogen-bridged Polyphenylene-based Materials for
Electronic Applications




Dissertation


Zur Erlangung des Grades

“Doktor der Naturwissenschaften”

am Fachbereich Chemie, Pharmazie und Geowissenschaften der
Johannes Gutenberg-Universität







Ashok Kumar Mishra
Geboren in Saharsha / India





Mainz, 2006

Table of Content

1. General introduction and Motivation
1.1 Overview of -conjugated polymers.......................................................1
1.2 Poly(p-phenylene) ……………………………………………………..2
1.2.1 Synthesis of PPP................................................................................3
1.2.1.1 Electrochemical Synthesis...........................................................3
1.2.1.1.1 Oxidative polymerization……………………………....3
1.2.1.1.2 Reductive polymerization………………………………4
1.2.1.2 Chemical Synthesis……………………………………………..5
1.2.1.2.1 Kovacic’s Synthesis.........................................................6
1.2.1.2.2 Catalytic and thermal dehydrogenation………………...7
1.2.1.2.3 Metal catalyzed coupling reaction……………………...8
1.3 Organic light emitting diodes…………………………………………..13
1.3.1 Electroluminescence device..............................................................14
1.3.1.1 Basic processes………………………………………………....14
1.3.1.2 Basic parameters………………………………………………..14
1.3.1.3 Blue-emitting materials…………………………………………15
1.3.1.4 Device structure……………………………………………….. 17
1.4 Polymeric solar cell……………………………………………………..21
1.4.1 Advantage of organic solar cell over Si cell………………………..21
1.4.2 Disadvantage of organic cell over Si cell…………………………..22
1.4.3 Basic working priniciple……………………………………………23
1.4.4 Device parameters…………………………………………………..24
1.4.5 Materials Used in organic solar cell………………………………...25
1.4.6 Device architecture………………………………………………….28
1.4.7 Current challenges…………………………………………………..31
1.5 Organic thin field-effect transistors……………………………………..31
1.5.1 Basic operation……………………………………………………...32
1.5.2 Materials used in OFETs……………………………………………33
1.5.2.1 p-Type semiconductor…………………………………………..34
1.5.2.2 n-Type semiconductor…………………………………………..36
1.6 Motivation of this work………………………………………………....38
1.6.1 Nitrogen-bridged semi-ladder-type polymers……………………….38
1.6.2 Carbazole-thiophene fused molecule for OFETs…………………....42
1.6.3 Aminocarbazole-anthraquinone fused dyes and polymers………….43
1.7 References……………………………………………………………….45
2. Nitrogen-bridged ladder-type polyphenylenes
2.1 Introduction………………………………………………………………50
2.1.1 Ladder-type polymers………………………………………………..50
2.1.1.1 Heteroatomic ladder-type polymers by multifunctional
polycondensation route………......................................................51
2.1.1.2 Conjugated ladder-type polymers by polymer analogous
cyclization……………………………………………………..…53
2.1.1.2.1 Carbon-bridged ladder-type polymers…………………...53
2.1.1.2.2 Nitrogen-bridged ladder-type polymers………………….55 2.2 Synthesis and characterization…………………………………………....60
2.2.1 Synthesis of poly(ladder-type tetraphenylene)………………………..62
2.2.1.1 Nitrogen-bridged poly(ladder-type tetraphenylene)……………....62
2.2.1.2 Carbon-bridged poly(ladder-type tetraphenylene)………………..63
2.2.1.3 Fully arylated carbon-bridged poly(ladder-type tetraphenylene)....64
2.2.2 Synthesis of nitrogen-bridged poly(ladder-type pentaphenylene)…….66
2.2.3 Synthesis of poly(ladder-type hexaphenylene)………………………..69
2.2.3.1 Poly(ladder-type hexaphenylene) with three nitrogen bridges…….69
2.2.3.2 Poly(ladder-type hexaphenylene) with one nitrogen bridges……...70
2.3 Photophysical properties…………………………………………………...72
2.3.1 Ladder-type monomers………………………………………………...72
2.3.1.1 All carbon-bridged ladder-type monomers………………………...72
2.3.1.2 Nitrogen-bridged ladder-type monomers…………………………..74
2.3.2 Ladder-type polymers………………………………………………….76
2.3.2.1 Poly(ladder-type tetraphenylene)…………………………………..76
2.3.2.2 Poly(ladder-type pentaphenylene)………………………………….80
2.3.2.3 Poly(ladder-type hexaphenylene)…………………………………..83
2.3.2.4 All carbon-bridged ladder-type polymers…………………………..87
2.3.2.5 Nitrogen-bridged ladder-type polymers…………………………….91
2.4 Electrochemical properties of ladder-type polymers……………………….94
2.4.1 Poly(ladder-type tetraphenylene)s……………………………………...94
2.4.2 Poly(ladder-type pentaphenylene)……………………………………...96
2.4.3 Poly(ladder-type hexaphenylene)s……………………………………...97
2.4.4 Comparison between all nitrogen-bridged polymers…………………...98
2.5 Stability of ladder-type polymers under oxidative environment……………99
2.5.1 Poly(ladder-type tetraphenylene)……………………………………….99
2.5.1.1 Nitrogen-bridged poly(ladder-type tetraphenylene)………………...99
2.5.1.2 Carbon-bridged poly(ladder-type tetraphenylene)………………….100
2.5.2 Poly(ladder-type hexaphenylene) with one nitrogen bridge……………101
2.6 Supramolecular organization of ladder-type polymers……………………..104
2.7 Application of ladder-type polymers in FETs………………………………113
2.8 Application of ladder-type polymers in PLEDs…………………………….122
2.8.1 Poly(ladder-type tetraphenylene)……………………………………….123
2.8.1.1 Nitrogen-bridged poly(ladder-type tetraphenylene)…………….......123
2.8.1.2 Carbon-bridged poly(ladder-type tetraphenylene)…………….........124
2.8.1.3 Fully arylated carbon-bridged poly(ladder-type tetraphenylene)… 126
2.8.2 Poly(ladder-type hexaphenylene) with one nitrogen bridges…………...128
2.9 Application of nitrogen-bridged polymers in solar cell……………………..130
2.9.1 Photoquenching in the film………………………………………………131
2.9.2 Photovoltaic devices with PCBM………………………………………..132
2.9.3 Relation between the polymer design, supramolecular order and
phovoltaic performance………………………………………………….134
2.9.4 Optimization of devices………………………………………………….136
2.10 Application of ladder-type polymers as gain medium in amplification
of blue light by amplified spontaneous emission……………………………138
2.11 Conclusions………………………………………………………………….147 2.12 References………………………………………………………………….150
3. Carbazole and thiophene fused oligomers
3.1 Introduction………………………………………………………………...153
3.2 Synthesis and optical properties……………………………………………154
3.3 2D-WAXS and POM studies……………………………………………….158
3.4 Application of oligomers in OFETs………………………………………...171
3.5 Conclusions…………………………………………………………………175
3.6 References…………………………………………………………………..176
4. Aminocarbazole-anthraquinone fused dyes and polymers
4.1 Introduction…………………………………………………………………178
4.1.1 Carbazole azo dyes……………………………………………………...179
4.1.2 Carbazole dyes with quinone groups……………………………………181
4.1.3 Dioxazine dyes…………………………………………………………..182
4.2 Synthesis and optical properties……………………………………………..184
4.3 Explanation of optical properties by resonance theory……………………...188
4.4 Synthesis of novel red-emitting material ……………………………………191
4.5 Unsucessful attempt of dehydration on compound 61………………………194
4.6 Polymer based on diaminocarbazole and dichloroanthraquinone…………...197
4.7 Conclusions………………………………………………………………….200
4.8 References…………………………………………………………………...201
5. Experimental details
5.1 Apparatus for analysis……………………………………………………….202
5.2 General procedures…………………………………………………………..203
5.2.1 Electroluminescence devices…………………………………………….203
5.2.2 Solar cell devices………………………………………………………...203
5.2.3 FET devices……………………………………………………………...203
5.3 Synthetic procedures…………………………………………………………204
6. Acknowledgement……………………………………………………………….251

Chapter 1
Introduction

1.1 Overview of -conjugated polymers
Conjugated polymers are macromolecules that possess alternating single and
double bonds along the main chain. These polymers combine the optoelectronic
properties of semiconductors with the mechanical properties and processing advantages
of plastics. When functionalized with flexible side groups, these materials become
soluble in organic solvents and can be solution processed at room temperature into large-
area, optical-quality thin films; such films are readily fabricated into desired shapes that
are useful in novel devices. The ease of polymer processing compared with conventional
inorganic semiconductors offers the potential for enormous cost-savings in applications
that require visible band-gap semiconductors. Some common conjugated polymers are
poly(acetylene) (PA), poly(thiophene) (PT), poly(pyrrole) (PPy), poly(p-phenylene)
(PPP), poly(p-phenylenevinylene) (PPV), poly(fluorene) (PF), poly(carbazole) (PCz) and
poly(phenanthrene) (PPh), which are illustrated in Figure 1.1.

* PA PT
PPy* n * ** * nn NS
H
PPVPPP * PF* *
*n * n
*
n
R R
R R

PPhPCz ** n * *
n
N
R

Figure 1.1 Structures of conjugated polymers
Chapter 1
The potential use of conjugated polymers in electronic devices was realized in the
late 1970s when electrically conductive polymers were discovered; i.e. Polyacetylene
1
doped with iodine. In recognition of this extraordinary discovery, the scientists
(Shirakawa, MacDiarmid, and Heeger) were jointly awarded the 2000 Nobel Prize in
Chemistry.
Many conjugated polymers that were studied in the early 1980s