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Polycyclic Aromatic Hydrocarbon Chemistry in a Spirit of Graphene Engineering

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Polycyclic Aromatic Hydrocarbon Chemistry in a Spirit of Graphene Engineering Polycyclic Aromatic Hydrocarbon Chemistry in a Spirit of Graphene Engineering Dissertation zur Erlangung des Grades “Doktor der Naturwissenschaften” am Fachbereich Chemie, Pharmazie und Geowissenschaften der Johannes Gutenberg-Universität Mainz und in Kooperation mit dem Max-Plank-Institut für Polymerforschung Mainz (Ian) Cheng-Yi Hou / 侯正一 geb. in München, Deutschland Mainz, 2020 1. Betrichterstatter: 2. Betrichterstatter: Tag der mündlichen Prüfung: 02.09.2020 Die vorliegende Arbeit wurde in der Zeit von Juli 2015 bis März 2020 im Max- Planck-Institut für Polymerforschung in Mainz unter der Betreuung von Prof. Dr. Klaus Müllen durchgeführt. Ich danke Prof. Dr. Klaus Müllen für seine wissenschaftliche und persönliche Unterstützung sowie für seine ständige Diskussionsbereitschaft. To my wife To Hong Kong and Taiwan To Freedom Table of Contents Abbreviations ................................................................................................................................................. 4 CHAPTER 1. INTRODUCTION ........................................................................................... 7 1.1 From an sp2-carbon to graphene .............................................................................................................. 7 1.1.1 Polycyclic aromatic hydrocarbons ......................................................................................................... 8 1.1.2 Graphene ................................................................................................................................................ 10 1.2 Quantization of graphene ....................................................................................................................... 14 1.2.1 Top-down graphene quantization ........................................................................................................ 14 1.2.2 Bottom-up synthesis of nanographenes on monocrystalline surface ................................................ 16 1.2.3 Organic synthetic strategy for large nanographenes ......................................................................... 17 1.2.4 Organic synthesis of large monodispersed graphene quantum dots ................................................. 23 1.2.5 Organic synthesis of wide graphene nanoribbons .............................................................................. 25 1.3 Defects in graphene and their model compounds .................................................................................. 31 1.3.1 Types of defects in graphene ................................................................................................................ 31 1.3.2 Relationship between organic compounds and graphene defects ..................................................... 35 1.3.3 Molecular models representing point defects in graphene ................................................................ 37 1.3.4 Molecular models related to topological non-trivial defects in graphene ......................................... 41 1.4 Controlling assemblies of nanographenes .............................................................................................. 47 1.4.1 Controlling 3D supramolecular assemblies of nanographenes .......................................................... 47 1.4.2 Controlling supramolecular assemblies of nanographenes at interfaces .......................................... 50 1.5 Motivation ............................................................................................................................................... 54 1.5.1 Synthesis of polyphenylenes as potential precursors for nanographenes approaching length scale of 5 nm ............................................................................................................................................................. 54 1.5.2 Bottom-up approach for nanostructures related to graphene grain boundaries ............................. 56 1.5.3 Exploring self-assemblies of hexa-peri-hexabenzocoronene derivatives ........................................... 58 1.6 References ............................................................................................................................................... 60 CHAPTER 2. SYNTHESIS OF DENDRITIC POLYPHENYLENES POSSESSING 366 AND 546 CARBONS AS POTENTIAL PRECURSORS FOR GIANT D6H- SYMMETRIC NANOGRAPHENES................................................................................... 72 2.1 Main text ................................................................................................................................................. 72 2.2 Supporting information .......................................................................................................................... 80 2.3 References ............................................................................................................................................... 97 CHAPTER 3. STEPWISE LATERAL EXTENSION OF PHENYL SUBSTITUTED LINEAR POLYPHENYLENES ........................................................................................... 99 3.1 Abstract .................................................................................................................................................. 99 3.2 Introduction .......................................................................................................................................... 101 1 3.3 Result and Discussion ........................................................................................................................... 104 3.4 Conclusion ............................................................................................................................................ 113 3.5 Experimental Section ............................................................................................................................ 114 3.6 Supporting information ........................................................................................................................ 123 3.7 References ............................................................................................................................................. 138 CHAPTER 4. ON-SURFACE SYNTHESIS OF POLYAZULENE WITH 2,6- CONNECTIVITY ................................................................................................................ 140 4.1 Abstract ................................................................................................................................................ 140 4.2 Main text ............................................................................................................................................... 141 4.3 Supporting information ........................................................................................................................ 148 4.4 References ............................................................................................................................................. 152 CHAPTER 5. ON-SURFACE SYNTHESIS OF SP2-CARBON-NANOSTRUCTURE WITH A SKELETON OF REGULARLY FUSED ALTERNATING PENTAGONS AND HEPTAGONS ............................................................................................................. 154 5.1 Main text ............................................................................................................................................... 154 5.2 Supporting information ........................................................................................................................ 159 5.3 References ............................................................................................................................................. 164 CHAPTER 6. PHOTO-MODULATION OF 2D-SELF-ASSEMBLY OF AZOBENZENE-HEXA-PERI-HEXABENZOCORONENE-AZOBENZENE TRIADS ................................................................................................................................................ 167 6.1 Abstract ................................................................................................................................................ 167 6.2 Introduction .......................................................................................................................................... 169 6.3 Result and discussion ............................................................................................................................ 171 6.4 Conclusion ............................................................................................................................................ 177 6.5 Experimental methods .......................................................................................................................... 178 6.6 Supporting information ........................................................................................................................ 181 6.7 References ............................................................................................................................................. 191 CHAPTER 7. HEXA-PERI-HEXABENZOCORONENE WITH DIFFERENT ACCEPTOR UNITS FOR TUNING OPTOELECTRONIC PROPERTIES ................ 194 2 7.1 Abstract ................................................................................................................................................ 194 7.2 Main text ..............................................................................................................................................
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