C_1tn3-symmetric discotic liquid crystalline materials for molecular electronics [Elektronische Ressource] : versatile synthesis and self-organization / vorgelegt von Xinliang Feng

Feng

Informations

• Publié par: johannes_gutenberg-universitat_mainz
• Publié le: 01 janvier 2008
• Nombre de lectures: 23
• Langue: Deutsch
• Poids de l'ouvrage: 16 Mo

Extrait

C -symmetric Discotic Liquid Crystalline 3
Materials for Molecular Electronics:
Versatile Synthesis and Self-organization Versatile Synthesis and Self-organization


Dissertation Dissertation


zur Erlangung des Grades
“Doktor der Naturwissenschaften”


dem Fachbereich Chemie und Pharmazie der
Johannes Gutenberg-Universität Mainz
vorgelegt von

Xinliang Feng
geboren in Anhui Province / P. R. China



Mainz, 2008












Decan: Herr Prof. Dr.
1. Berichterstatter: Herr Prof. Dr. 1. Berichterstatter: Herr Prof. Dr.
2. Berichterstatter: Herr Prof. Dr.
Tag der mündlichen Prüfung:


Die vorliegende Arbeit wurde in der Zeit von September
2004 bis Februar 2008 im Max-Planck-Institut für 2004 bis Februar 2008 im Max-Planck-Institut für
Polymerforschung in Mainz unter Anleitung von Herrn Prof.
Dr. Müllen ausgeführt.










Ich danke Herrn Prof. Dr. K. Müllen für seine Ich danke Herrn Prof. Dr. K. Müllen für seine
wissenschaftliche und persönliche Unterstützung sowie für
seine ständige Diskussionsbereitschaft. Table of Contents
Table of Contents

Chapter 1. Introduction......................................................................................1
1.1. Polycyclic Aromtaic Hydrocarbons...……….....................…....…………. ..1
1.1.1. Synthesis………………………..…………………………………………………….3
1.1.1.1. Intra- and intermolecular Diels-Alder reaction………………...…………………...3
1.1.1.2. Ring-closing olefin metathesis (RCM)……………………………………..………5
1.1.1.3. Benzannulation and electrophilic cyclization…………………………….………...6
1.1.1.4. Intramolecular photocyclization of stilbene type compounds….…………………..7
1.1.1.5. Flash vacuum pyrolysis…………………………………………………………….8
1.1.1.6. Oxidative cyclodehydrogenation……………………………………………….…..9
1.2. Self-organization and Discotic Liquid Crystals……...…………...…….....11
1.2.1. Introduction and materials………………………………………………………...…11
1.2.2. Characterization of the self-organization…………..………………………………..15
1.2.3. Self-assembly of discotics on the surface……………………………………………17
1.2.4. DLCs for electronic devices………………………………………………………….19
1.2.4.1. Organic field effect transistors (OFETs)…………………………………………...20
1.2.4.2. Bulk heterojunction photovoltaic cells……………………………………….…….21
1.2.4.3. Organic light emitting diodes (OLEDs)……………………………………………21
1.3. Motivation……………………………………………………………..…..22
1.4. References..………………………………………………………………..27

Chapter 2. The Role of Oligophenylene Precursors for Oxidative
Cyclodehydrogenation and Unusual Symmetry Effect on Thermal Behavior
and Self-assembly of Hexa-peri-hexabenzocoronene.....................................34
2.1. Hexa-peri-hexabenzocoronenes by Efficient Oxidative
Cyclodehydrogenation—the Role of the Oligophenylene Precursors…….…....34
2.1.1. Introduction…………………………….......……………...……………………….34
2.1.2. Synthesis…………..……………………………………………………………….36
2.1.3. Summary……………… ………………………………………………………….41
2.2. Unusual Symmetry Effect on Thermal behavior and Self-assembly of Hexa-
peri-hexabenzocoronene……………………………………..……………..….41
I 2.2.1. Introduction…………..………….......………………….....……………………….41
2.2.2. Synthesis…………………………………………………………………………...43
2.2.3. Thermal behavior and self-assembly at the solid-liquid interface…………………44
2.2.4. Summary…………………………………………………………………………...49
2.2.5. References………………………………………………………………………….50

Chapter 3. C symmetric Hexa-peri-hexabenzocoronenes with Alternating 3
Polar/Apolar Substituents…………………...………………………………..53
3.1. Controlling Columnar Orientation of C –symmetric “Superbenzenes” by 3
Alternating Polar/Apolar Substituents..........………………………………. 53
3.1.1. Introduction…………..………….......………………….....……………………….53
3.1.2. Synthesis, structure characterization and self-aggregation in solution…..………...54
3.1.3. Bulk characterization in the solid state……………………………….……………61
3.1.4. Self-assembly in solution and on the surface……………………………………...64
3.1.5. Conclusion...……………………………………………………………………….68
3.2. Synthesis, Helical Organization, and Long-range Fibrous Assembly of C 3
symmetric Hexa-peri-hexabenzocoronene with Methoxy groups………..…68
3.2.1. Introduction…………..………….......………………….....……………………….68
3.2.2. Synthesis and self-assembly in the solution……………………………...………...70
3.2.3. Bulk characterization and self-assembly on the surface…..………….……………73
3.2.4. Conclusion……………………………………….………………………………...77
3.2.5. References...……………………………………………………………… ……….77

Chapter 4. Triangle-shaped Polycyclic Aromatic Hydrocarbons..............81
4.1. Versatile Synthesis and Self-assembly of Triangle-shaped Polycyclic
Aromatic Hydrocarbons…………………………………………….…………..81
4.1.1. Introduction…………..………….......………………….....……………………….81
4.1.2. Synthesis and structure characterization………………………………….………..84
4.1.3. Bulk characterization and self-assembly at solid-liquid interface…………………94
4.1.4. Conclusion…………………………………….…………………………………...98
II Table of Contents
4.2. Supramolecular Organization and Photovoltaics of Triangle-shaped Discotic
Graphenes with Swallow-tailed Alkyl Substituents……………...……….....…98
4.2.1. Introduction…………..………….......………………….....……………………….99
4.2.2. Synthesis and structure characterization………………...……………….……….101
4.2.3. Bulk characterization ……………………………………………..………...……104
4.2.4. Photovoltaic device characterizations…….……………………………………....107
4.2.5. Conclusion………………………………………………………………………..110
4.2.6. References………………………………………………………………………...111

Chapter 5. Controlling the Helical and Staggered Stacking of
Nanographenes……………………………………………………………....116
5.1. From Helical to Staggered Stacking of Biszigzag Nanographenes………117
5.1.1. Introduction…………..………….......………………….....……………………...117
5.1.2. Synthesis and structure characterizations……………………………….………...117
5.1.3. Self-organization in the bulk………………………………………..………….…121
5.1.4. Conclusion…………………………………….………………………………….125
5.2. Rational Design of the Shape and periphery of Discotic Liquid Crystals: a
synthetic way towards high charge carrier mobilities…………………..…….126
5.2.1. Introduction…………..………….......………………….....……………………...126
5.2.2. Synthesis and structure characterization………………………….…….………...131
5.2.3. Bulk characterizations……………………………………..…………………..…133
5.2.4. Computer simulations...……………………….………………………………….135
5.2.4.1. Molecular model and simulation details………………………………………..135
5.2.4.2. Results and discussion………………………………………………………….136
5.2.5. Charge transport…………………………………………………………………..140
5.2.6. Conclusion………………………………………………………………………..141
5.2.7. References………………………………………………………………………...141

Chapter 6. Summary and Outlook…………………………………….…...145

Chapter 7. Experimental Section...………………………………………....153

IIIPublication List………………………………………………………………211

Curriculum Vitae.............................................................................................212

Acknowledgments............................................................................................213

IV Index of Abbreviations

2D-WAXS two-dimensional wide angle X-ray scattering
AFM atomic force microscopy
DCM dichloromethane
DSC differential scanning calorimetry
EA elemental analysis
FD MS field desorption mass spectroscopy
FET field effect transistor
HBC hexa-peri-hexabenzocoronene
HOMO highest occupied molecular orbital
h hour
LED light emitting diode
LUMO lowest unoccupied molecular orbital
MeOH methanol
MS mass spectroscopy
min minute
m.p. melting point
MALDI-TOF matrix-assisted laser desorption ionization –time of flight
NMR nuclear magnetic resonance
PE petroleum ether
PAH polycyclic aromatic hydrocarbons
POM polarized optical microscopy
RT room temperature
STM scanning tunneling microscopy
TCNQ 7,7,8,8-tetracyanoquinodimethane
THF tetrahydrofuran
TLC thin layer chromatography
TMS trimethylsilyl
Tolane diphenylacetylene
UV-vis ultraviolet/visible Introduction