Discotic Materials for Organic Electronics

Total Page:16

File Type:pdf, Size:1020Kb

Discotic Materials for Organic Electronics Discotic Materials for Organic Electronics Dissertation zur Erlangung des Grades “Doktor der Naturwissenschaften” am Fachbereich Chemie, Pharmazie und Geowissenschaften der Johannes Gutenberg-Universität Mainz Marcel Kastler geboren in Weilburg Mainz, 2006 Dekan: 1. Berichterstatter: 2. Berichterstatter: Tag der mündlichen Prüfung: Herrn Prof. Dr. K. Müllen, unter dessen Anleitung ich die vorliegende Arbeit am Max-Planck Institut für Polymerforschung in Mainz in der Zeit von Dezember 2002 bis Dezember 2005 angefertigt habe, danke ich für seine wissenschaftliche und persönliche Unterstützung sowie seine ständige Diskussionsbereitschaft. Dedicated to my parents Contents 1 Introduction................................................................................................................ 1 1.1 Organic Electronics........................................................................................... 1 1.2 Why Discotics?.................................................................................................. 2 1.3 Polycyclic aromatic hydrocarbons..................................................................... 6 1.3.1 Synthesis 7 1.3.1.1 FRIEDEL-CRAFTS-type Reactions ........................................................... 7 1.3.1.2 DIELS-ALDER Cycloaddition.................................................................. 8 1.3.1.3 Photocyclization .................................................................................... 9 1.3.1.4 Flash Vacuum Pyrolysis (Thermolysis)............................................... 10 1.3.1.5 Extrusion of Heteroatoms .................................................................... 11 1.3.1.6 SCHOLL-Cyclodehydrogenation........................................................... 12 1.4 Supramolecular Organization.......................................................................... 14 1.4.1 Self-assembly 14 1.4.2 Orientation on Substrates 16 1.4.3 Characterization of the Organization 16 1.5 Processing........................................................................................................ 20 1.6 Electronic Devices ........................................................................................... 23 1.6.1 Light Emitting Diode 23 1.6.2 Photovoltaic Element 23 1.6.3 Field-Effect Transistor 25 1.7 References........................................................................................................ 26 2 Motivation and Objective........................................................................................ 31 2.1 References........................................................................................................ 35 3 Hexa-peri-hexabenzocoronenes with Improved Processability .............................. 37 3.1 Synthesis.......................................................................................................... 39 3.2 Self-Assembly.................................................................................................. 43 3.2.1 NMR Investigation 44 3.2.2 Electronic Spectroscopy 51 3.2.3 Conclusion 56 3.3 Processing.........................................................................................................61 3.3.1 Solution Processing 61 3.3.2 Melt Processing 67 3.3.2.1 Morphology..........................................................................................67 3.3.2.2 Characterization of the molecular orientation......................................72 3.3.2.3 Mechanism of the Homeotropic Phase Formation...............................77 3.3.2.4 Zone-Crystallization.............................................................................81 3.3.3 Mechanical Alignment - Structural Investigation 83 3.3.3.1 Thermal Behavior.................................................................................83 3.3.3.2 Mechanically Aligned Fibers ...............................................................85 3.3.3.3 Molecular Dynamics ............................................................................89 3.3.3.4 Manipulation of the Superstructure......................................................93 3.4 Charge Carrier Mobility.................................................................................102 3.4.1 Pulse-Radiolysis Time-Resolved Microwave Conductivity 102 3.4.2 Life-Time of Charge Carriers 104 3.4.3 Time-of-Flight 109 3.5 Implementation in Photovoltaic Devices .......................................................115 3.6 Organization in porous materials – Pyrolysis ................................................119 3.7 Summary ........................................................................................................125 3.8 References ......................................................................................................127 4 Functionalization of Hexa-peri-hexabenzocoronenes............................................135 4.1 Attachment of a Chromophore.......................................................................136 4.2 a posteriori Functionalizations.......................................................................144 4.2.1 Synthesis 145 4.2.2 Supramolecular Organization 148 4.3 “Tailoring” Supramolecular Properties..........................................................153 4.4 Structure-Property Relation............................................................................159 4.5 Chemical Cross-Linking of Hexa-peri-hexabenzocoronene.......................... 161 4.5.1 Fixation of supramolecular organizations 161 4.5.2 Nanostructuring 165 4.6 Summary........................................................................................................ 171 4.7 References...................................................................................................... 172 5 Polycyclic Aromatic Hydrocarbons with Different Peripheries............................ 177 5.1 Nomenclature................................................................................................. 177 5.2 Clar-Rule and Peripheries.............................................................................. 180 5.3 Electronic Spectroscopy of PAHs ................................................................. 182 5.4 Introduction of “zigzag” Sites ....................................................................... 187 5.4.1 Tetrabenzo[bc,ef,hi,uv]ovalene 188 5.4.2 Dibenzo[hi,uv]phenanthro-[3,4,5,6-bcdef]-ovalene 201 5.4.3 Diphenanthro[3,4,5,6-uvabc;3',4',5',6'-efghi]ovalene 211 5.4.4 Dibenzo[ef,hi]phenanthro[3,4,5,6-u,v,a,b,c]ovalene 218 5.4.5 Circumcoronene 221 5.5 Electronic Spectroscopy of the “zigzag” PAHs............................................. 224 5.5.1 Aromatic Core Symmetry 224 5.5.2 Self-Association in Solution 231 5.6 Supramolecular Organization........................................................................ 233 5.6.1 Introduction of a Novel Substitution Pattern 233 5.6.2 Self-Assembly in the Bulk Phase 235 5.6.3 Self-Assembly on Surfaces 239 5.7 Functionalization of PAHs in the Periphery.................................................. 250 5.7.1 3H-Cyclopenta[cde]hexa-peri-hexabenzocoronene 251 5.7.2 Investigation of the Supramolecular Self-Organization 255 5.7.3 Functionalization 261 5.7.4 Other “Reactive” Peripheries 264 5.8 Graphite with “Defects”................................................................................. 268 5.8.1 Synthesis of an Extended PAH with “Hole” 268 5.8.2 Engineering of microporous organic crystals 275 5.8.3 Phase Forming Ring 277 5.8.4 Non-planar PAHs with hole 281 5.8.5 Softlanding 284 5.9 Summary ........................................................................................................287 5.10 References ......................................................................................................289 6 Conclusion and Outlook.........................................................................................299 7 Experimental Part...................................................................................................305 7.1 General methods.............................................................................................305 7.1.1 Chemicals and solvents 305 7.1.2 Chromatography 305 7.1.3 Microwave Assisted Reactions 305 7.1.4 Inert atmosphere 305 7.2 Analytical techniques.....................................................................................306 7.2.1 Mass spectrometry 306 7.2.2 NMR spectroscopy 306 7.2.3 Elemental Analysis 306 7.2.4 UV/vis spectroscopy 306 7.2.5 Photoluminescence spectroscopy 307 7.2.6 Differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) 307 7.2.7 Polarization microscopy 307 7.2.8 X-Ray Diffractometry 307 7.2.9 Single crystal analysis 308 7.2.10 Synchrotron experiments 308 7.2.11 Pulse-radiolysis time-resolved microwave conductivity investigation 308 7.2.12 Time-of-flight experiments 309 7.2.13 Electrochemical Characterization 309 7.2.14 Preparation of Photovoltaic Devices 310 7.3 Synthesis.........................................................................................................311 7.3.1 4,4’-Bis(2-ethyl-hexyl)diphenylacetylene (3-11a) 311 7.3.2 Hexa-(4-(2-ethyl-hexyl-))phenylbenzene (3-12a) 311 7.3.3 2,5,8,11,14,17-Hexa(4-(2-ethyl-hexyl-)-hexa-peri-hexabenzocoronene (3-13a) 312 7.3.4 4,4’-Bis(2-hexyl-decyl)diphenylacetylene (3-11b) 313 7.3.5 Hexa-(4-(2-hexyl-decyl-))phenylbenzene (3-12b) 313 7.3.6 2,5,8,11,14,17-Hexa(2-hexyl-decyl)-hexa-peri-hexabenzocoronene (3-13b) 314 7.3.7 2-Decyl-tetradecylbromide (3-10c)
Recommended publications
  • Hexa-Peri-Hexabenzocoronene in Organic Electronics*
    Pure Appl. Chem., Vol. 84, No. 4, pp. 1047–1067, 2012. http://dx.doi.org/10.1351/PAC-CON-11-09-24 © 2012 IUPAC, Publication date (Web): 13 March 2012 Hexa-peri-hexabenzocoronene in organic electronics* Helga Seyler, Balaji Purushothaman, David J. Jones, Andrew B. Holmes, and Wallace W. H. Wong‡ School of Chemistry, Bio21 Institute, University of Melbourne, 30 Flemington Road, Parkville, Victoria 3010, Australia Abstract: Polycyclic aromatic hydrocarbons (PAHs) are in a class of functional organic com- pounds with increasing importance in organic electronics. Their tunable photophysical prop- erties and typically strong intermolecular associations make them ideal materials in applica- tions where control of charge mobility is essential. Hexa-peri-hexabenzocoronene (HBC) is a disc-shaped PAH that self-associates into columnar stacks through strong π–π interactions. By decorating the periphery of the HBC molecule with various substituents, a range of prop- erties and functions can be obtained including solution processability, liquid crystallinity, and semiconductivity. In this review article, the synthesis, properties, and functions of HBC derivatives are presented with focus on work published in the last five years. Keywords: hexabenzocoronene; materials chemistry; molecular electronics; organic electron- ics; organic semiconductors; photovoltaics; polycyclic aromatics; self-organization. INTRODUCTION Polycyclic aromatic hydrocarbons (PAHs) are defined as fused ring materials consisting of sp2 carbon centers and can be considered as segments of graphite. The dominant intermolecular force is often face- to-face π–π interactions with some examples of face-to-edge (or herringbone) assembly. Although PAHs can often be found naturally in combustion residues, analytically pure and discrete PAHs can only be obtained through synthesis.
    [Show full text]
  • Topological Analysis of Pahs Using Irregularity Based Indices
    Article Volume 12, Issue 3, 2022, 2970 - 2987 https://doi.org/10.33263/BRIAC123.29702987 Topological Analysis of PAHs using Irregularity based Indices Julietraja Konsalraj 1,* , Venugopal Padmanabhan 2 , Chellamani Perumal 3 1 Department of Mathematics, Sri Sivasubramaniya Nadar College of Engineering, Kalavakkam – 603 110, India; [email protected] (J.K.); 2 Department of Mathematics, Shiv Nadar University Chennai, Kalavakkam – 603 110, India; [email protected] (V.P.); 3 Department of Mathematics, Sacred Heart College (Autonomous), Tirupattur – 635 601, Tirupattur Dt., India; [email protected] (C.P.); * Correspondence: [email protected] (J.K.); Scopus Author ID 57218631900 Received: 8.06.2021; Revised: 15.07.2021; Accepted: 22.07.2021; Published: 8.08.2021 Abstract: Topological descriptors are non-empirical graph invariants that characterize the structures of chemical molecules. The structural descriptors are vital components of QSAR/QSPR studies which form the basis for theoretical chemists to design and investigate new chemical structures. Irregularity indices are a class of topological descriptors that have been employed to study certain chemical properties of compounds. This article aims to compute analytical expressions of irregularity indices for three important classes of polycyclic aromatic hydrocarbons. The intriguing properties of these classes of compounds have several potential applications in wide-raging fields, which warrant a study of their properties from a structural perspective. Additionally, the 3D graphical representations of a few indices are presented, which will aid in analyzing the similarity of behavior among the indices. Keywords: topological descriptors; benzenoid systems; graph-theoretical methods; irregularity indices. © 2021 by the authors. This article is an open-access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https://creativecommons.org/licenses/by/4.0/).
    [Show full text]
  • Expanded Aromatic Monomers for Functional Porous Polymers
    EXPANDED AROMATIC MONOMERS FOR FUNCTIONAL POROUS POLYMERS by Arosha Aruni Kumari Karunathilake APPROVED BY SUPERVISORY COMMITTEE: ___________________________________________ Dr. Ronald A. Smaldone, Chair ___________________________________________ Dr. Michael C. Biewer ___________________________________________ Dr. John W. Sibert ___________________________________________ Dr. Yves J. Chabal Copyright 2017 Arosha Aruni Kumari Karunathilake All Rights Reserved To my loving parents and to my loving husband, Eranda EXPANDED AROMATIC MONOMERS FOR FUNCTIONAL POROUS POLYMERS by AROSHA ARUNI KUMARI KARUNATHILAKE, BS DISSERTATION Presented to the Faculty of The University of Texas at Dallas in Partial Fulfillment of the Requirements for the Degree of DOCTOR OF PHILOSOPHY IN CHEMISTRY THE UNIVERSITY OF TEXAS AT DALLAS May 2017 ACKNOWLEDGMENTS First and foremost, I would like to acknowledge my research advisor and mentor, Dr. Ronald A. Smaldone, for his endless scientific guidance, unwavering support and enthusiasm throughout the years. His guidance and encouragement were always behind my success. I thank members of my supervisory committee Dr. Michael C. Biewer, Dr. John W. Sibert and Dr. Yves J. Chabal for their constructive advice and new ideas. Their advice and comments helped me to add value to my research work and to come up with high quality outputs. I respect and appreciate all my colleagues from the Smaldone group, both past and present: Dr. Christina Thompson for getting me started in the lab and introducing me to projects, Dr. Sumudu Wijenayake for enduring friendship and technical expertise, Fei Li for his support and encouragement at my early years, Sampath Alhakoon for his valuable discussions and always being there to help me, Gayan Adikari for his friendship, support and encouragement, Yinhuwan Xie for positive attitude and sense of humor, Vicky, Josh, Daniel and Grant for their helpful nature and company.
    [Show full text]
  • Heteroatom-Containing Carbon Nanostructures As Oxygen Reduction Electrocatalysts for PEM and Direct Methanol Fuel Cells
    Heteroatom-containing Carbon Nanostructures as Oxygen Reduction Electrocatalysts for PEM and Direct Methanol Fuel Cells Dissertation Presented in Partial Fulfillment of the Requirements for the Degree Doctor of Philosophy in the Graduate School of The Ohio State University By Dieter von Deak, B.S.ChE Graduate Program in Chemical Engineering * * * * The Ohio State University 2011 Dissertation Committee: Professor Umit S. Ozkan, Advisor Professor David Wood Professor James Rathman Copyright by Dieter von Deak 2011 2 ABSTRACT The main goal of this work was to undertake a fundamental investigation of precious metal-free carbon catalysts nano-structure modification to enable their use as oxygen reduction reaction (ORR) catalysts in proton exchange membrane (PEM) fuel cells. The sluggish ORR is accelerated by fiscally prohibitive loadings of Pt catalyst. The expense and availability of platinum motivate the development of non-precious metal carbon-nitroge-based ORR catalysts (CNx). The project targets the nature of oxygen reduction reaction active sites and exploring ways to create these sites by molecular tailoring of carbon nano-structures. CNx grown with phosphorous had a significant increase in the ORR active site density. CNx catalyst growth media was prepared by acetonitrile deposition over a Fe and P impregnated MgO. Rotating Ring Disk Electrode (RRDE) Activity and selectivity showed a significant increase in oxygen reduction current with CNx grown with less than a 1:1 molar ratio of P:Fe. Selectivity for the full reduction of dioxygen to water trended with increasing ORR activity for phosphorous grown CNx catalysts. Phosphorus growth altered the morphology of carbon-nitride graphite formed during pyrolysis.
    [Show full text]
  • Large Polycyclic Aromatic Hydrocarbons: Synthesis and Discotic Organization*
    Pure Appl. Chem., Vol. 81, No. 12, pp. 2203–2224, 2009. doi:10.1351/PAC-CON-09-07-07 © 2009 IUPAC, Publication date (Web): 31 October 2009 Large polycyclic aromatic hydrocarbons: Synthesis and discotic organization* Xinliang Feng‡, Wojciech Pisula†, and Klaus Müllen** Max Planck Institute for Polymer Research, Ackermannweg 10, 55128 Mainz, Germany Abstract: Polycyclic aromatic hydrocarbons (PAHs) have attracted enormous interest due to their unique electronic and optoelectronic properties as well as the potential applications in organic electronics. This article reviews the progress in the modern synthesis of large PAHs with different sizes, shapes, edge structures, and substituents. Due to their outstanding self- organization characteristics, the discotic liquid-crystalline properties, self-assembled nanostructures on the surfaces, as well as the application in electronic devices will be discussed. Keywords: discotic liquid crystals; hexabenzocoronene; nanographene; polycyclic aromatic hydrocarbons; self-assembly. INTRODUCTION Polycyclic aromatic hydrocarbons (PAHs) are a class of unique compounds that consist of fused con- jugated aromatic rings and do not contain heteroatoms or carry substituents [1]. These compounds can be point source (e.g., oil spill) or non-point source (e.g., atmospheric deposition) and are one of the most widespread organic pollutants. Some of them are known or suspected carcinogens, and are linked to other health problems. They are primarily formed by incomplete combustion of carbon-containing fuels such as wood, coal, diesel, fat, tobacco, or incense [2,3]. Tar also contains PAHs. Different types of combustion yield different distributions of individual PAHs which can also give rise to isomers. Hence, those produced from coal combustion are in contrast to those yielded by motor-fuel combustion, which differ from those produced by forest fires.
    [Show full text]
  • Synthesis of Novel Fluorinated Hexa-Peri-Hexabenzocoronenes Synthesisolivier of Fluorinated Hexa-Peri-Hexabenzocoronenes F
    PAPER 2891 Synthesis of Novel Fluorinated Hexa-peri-hexabenzocoronenes SynthesisOlivier of Fluorinated Hexa-peri-hexabenzocoronenes F. Aebischer,a Patrick Tondo,a Bassam Alameddine,b Titus A. Jenny*a a Chemistry Department, University of Fribourg, 9 chemin du Musée, 1700 Fribourg, Switzerland Fax +41(26)3009739; E-mail: [email protected] b Chemistry Department, University of Balamand, P.O. Box 100, Tripoli, Lebanon Received 5 May 2006; revised 24 May 2006 volves the cobalt-catalysed7 cyclotrimerisation of the Abstract: The synthesis of several perfluoroalkylated hexabenzo- coronene derivatives is described. The substituents range from lin- corresponding disubstituted tolane derivatives 3, yielding ear semiperfluoroalkylated chains to branched perfluoroalkylated hexaphenylbenzene moieties 2, which are subsequently 8 chains. Novel strategies were applied to overcome the low solubili- cyclodehydrogenated, under the Kovacic conditions, in ty and the low reactivity of such chains. which the iron(III) chloride reagent acts as both Lewis Key words: coronenes, tolanes, perfluoroalkyl substituents, cross- acid and oxidant (Scheme 1). The latter conditions, how- coupling, cyclodehydrogenation ever, prevent the preparation of HBC derivatives in which perfluorinated side chains are directly attached to the core. An alkyl spacer of at least two carbons, or an ether or thio- Polycondensed aromatic hydrocarbons (PAHs) represent ether linkage is required to reduce the electron-withdraw- a widely investigated class of aromatic compounds and ing effect of the perfluorinated side chain to an acceptable have been extensively studied over the past decades.1 level for the mild iron(III) chloride reagent to be success- 5 Hexa-peri-hexabenzocoronene (HBC), an all-benzoid ful. The main task remains, therefore, in the preparation PAH containing thirteen fused benzene rings, possesses of the symmetrically substituted tolane derivatives 3 high thermal and chemical stability.
    [Show full text]
  • Synthesis of Contorted Nanographenes Via Multi-Fold Alkyne Benzannulation Reactions
    University of Nevada, Reno Synthesis of contorted nanographenes via multi-fold alkyne benzannulation reactions A dissertation submitted in partial fulfillment of the Requirements for the degree of Doctor of Philosophy in Chemistry by Paban Sitaula Prof. Dr. Wesley. A. Chalifoux/ Dissertation Advisor: May 2020 Copyright by Paban Sitaula 2020 All Rights Reserved THE GRADUATE• SCHOOL We recommend that the dissertation prepared under our supervision by entitled be accepted in partial fulfillment of the requirements for the degree of Advisor Committee Member Committee Member Committee Member Graduate School Representative David W. Zeh, Ph.D., Dean Graduate School i Abstract Nanographenes (NGs) of unique shape, size and properties are always at the center of attraction because of their potential application as semiconducting materials in organo-electronic devices. Contorted NGs have gained increased attention because of their fascinating molecular packing, reduced π-π interaction, enhanced solubility and lower band gap compared to the planar analogues. We have synthesized a library of contorted NGs by utilizing the non-oxidative, alkyne benzannu- lation reaction catalyzed by indium chloride and silver bis triflimide by exploiting high energy content of carbon-carbon triple bonds of the diyne precursors under a mild-reaction conditions. We employed two-fold InCl3/AgNTf2-catalyzed alkyne benzannulation reaction to afford a broad collection of highly functionalized, laterally π-expanded, [5]helicene-like naphtho[1,2-a]pyrene derivatives in moderate to very good yields. We were able to utilize this method to expand conju- gation of the HBC core to get a variety of π-extended HBC NGs. The Suzuki cross-coupling of the halogen(s) substituted smaller polycyclic aromatic hydrocarbons with diyne boronic ester gave polyalkyne precursors, which were subjected to multi-fold alkyne benzannulation reaction to af- ford larger, highly soluble contorted NGs.
    [Show full text]
  • Hexa-Peri-Hexabenzocoronene in Organic Electronics*
    Pure Appl. Chem., Vol. 84, No. 4, pp. 1047–1067, 2012. http://dx.doi.org/10.1351/PAC-CON-11-09-24 © 2012 IUPAC, Publication date (Web): 13 March 2012 Hexa-peri-hexabenzocoronene in organic electronics* Helga Seyler, Balaji Purushothaman, David J. Jones, Andrew B. Holmes, and Wallace W. H. Wong‡ School of Chemistry, Bio21 Institute, University of Melbourne, 30 Flemington Road, Parkville, Victoria 3010, Australia Abstract: Polycyclic aromatic hydrocarbons (PAHs) are in a class of functional organic com- pounds with increasing importance in organic electronics. Their tunable photophysical prop- erties and typically strong intermolecular associations make them ideal materials in applica- tions where control of charge mobility is essential. Hexa-peri-hexabenzocoronene (HBC) is a disc-shaped PAH that self-associates into columnar stacks through strong π–π interactions. By decorating the periphery of the HBC molecule with various substituents, a range of prop- erties and functions can be obtained including solution processability, liquid crystallinity, and semiconductivity. In this review article, the synthesis, properties, and functions of HBC derivatives are presented with focus on work published in the last five years. Keywords: hexabenzocoronene; materials chemistry; molecular electronics; organic electron- ics; organic semiconductors; photovoltaics; polycyclic aromatics; self-organization. INTRODUCTION Polycyclic aromatic hydrocarbons (PAHs) are defined as fused ring materials consisting of sp2 carbon centers and can be considered as segments of graphite. The dominant intermolecular force is often face- to-face π–π interactions with some examples of face-to-edge (or herringbone) assembly. Although PAHs can often be found naturally in combustion residues, analytically pure and discrete PAHs can only be obtained through synthesis.
    [Show full text]
  • I. Contorted Polycyclic Aromatic Hydrocarbons: Attempted Synthesis of [12]Circulene Derivatives Ii
    University of Vermont ScholarWorks @ UVM Graduate College Dissertations and Theses Dissertations and Theses 2019 I. Contorted Polycyclic Aromatic Hydrocarbons: Attempted Synthesis Of [12]circulene Derivatives Ii. Synthesis And Characterization Of Novel [1]benzothieno[3,2-B][1]benzothiophene Derivatives Jonathan Hollin University of Vermont Follow this and additional works at: https://scholarworks.uvm.edu/graddis Part of the Organic Chemistry Commons Recommended Citation Hollin, Jonathan, "I. Contorted Polycyclic Aromatic Hydrocarbons: Attempted Synthesis Of [12]circulene Derivatives Ii. Synthesis And Characterization Of Novel [1]benzothieno[3,2-B][1]benzothiophene Derivatives" (2019). Graduate College Dissertations and Theses. 992. https://scholarworks.uvm.edu/graddis/992 This Dissertation is brought to you for free and open access by the Dissertations and Theses at ScholarWorks @ UVM. It has been accepted for inclusion in Graduate College Dissertations and Theses by an authorized administrator of ScholarWorks @ UVM. For more information, please contact [email protected]. I. CONTORTED POLYCYCLIC AROMATIC HYDROCARBONS: ATTEMPTED SYNTHESIS OF [12]CIRCULENE DERIVATIVES II. SYNTHESIS AND CHARACTERIZATION OF NOVEL [1]BENZOTHIENO[3,2-b][1]BENZOTHIOPHENE DERIVATIVES A Dissertation Presented by Jonathan William Lawrence Hollin to The Faculty of the Graduate College of The University of Vermont In Partial Fulfillment of the Requirements for the Degree of Doctor of Philosophy Specializing in Chemistry January, 2019 Defense Date: September 28, 2018 Dissertation Examination Committee: Adam C. Whalley, Ph. D., Advisor John M. Hughes, Ph. D., Chairperson Matthias Brewer, Ph. D. Matthew D. Liptak, Ph, D. Cynthia J. Forehand, Ph. D., Dean of the Graduate College ABSTRACT There has been increasing interest in the development of organic materials due to their unique structural and electronic properties.
    [Show full text]
  • Discotic Materials for Organic Electronics
    Discotic Materials for Organic Electronics Dissertation zur Erlangung des Grades “Doktor der Naturwissenschaften” am Fachbereich Chemie, Pharmazie und Geowissenschaften der Johannes Gutenberg-Universität Mainz Marcel Kastler geboren in Weilburg Mainz, 2006 Dekan: 1. Berichterstatter: 2. Berichterstatter: Tag der mündlichen Prüfung: Herrn Prof. Dr. K. Müllen, unter dessen Anleitung ich die vorliegende Arbeit am Max-Planck Institut für Polymerforschung in Mainz in der Zeit von Dezember 2002 bis Dezember 2005 angefertigt habe, danke ich für seine wissenschaftliche und persönliche Unterstützung sowie seine ständige Diskussionsbereitschaft. Dedicated to my parents Contents 1 Introduction................................................................................................................ 1 1.1 Organic Electronics........................................................................................... 1 1.2 Why Discotics?.................................................................................................. 2 1.3 Polycyclic aromatic hydrocarbons..................................................................... 6 1.3.1 Synthesis 7 1.3.1.1 FRIEDEL-CRAFTS-type Reactions ........................................................... 7 1.3.1.2 DIELS-ALDER Cycloaddition.................................................................. 8 1.3.1.3 Photocyclization .................................................................................... 9 1.3.1.4 Flash Vacuum Pyrolysis (Thermolysis)..............................................
    [Show full text]
  • Polycyclic Aromatic Hydrocarbons in the Graphene Era SCIENCE CHINA
    SCIENCE CHINA Chemistry •INVITED REVIEWS• September 2019 Vol.62 No.9: 1099–1144 https://doi.org/10.1007/s11426-019-9491-2 Polycyclic aromatic hydrocarbons in the graphene era Xiao-Ye Wang1,2*, Xuelin Yao1 & Klaus Müllen1* 1Max Planck Institute for Polymer Research, Ackermannweg 10, 55128 Mainz, Germany; 2State Key Laboratory of Elemento-Organic Chemistry, College of Chemistry, Nankai University, Tianjin 300071, China Recieved February 25, 2019; accepted April 29, 2019; published online June 25, 2019 Polycyclic aromatic hydrocarbons (PAHs) have been the subject of interdisciplinary research in the fields of chemistry, physics, materials science, and biology. Notably, PAHs have drawn increasing attention since the discovery of graphene, which has been regarded as the “wonder” material in the 21st century. Different from semimetallic graphene, nanoscale graphenes, such as graphene nanoribbons and graphene quantum dots, exhibit finite band gaps owing to the quantum confinement, making them attractive semiconductors for next-generation electronic applications. Researches based on PAHs and graphenes have expanded rapidly over the past decade, thereby posing a challenge in conducting a comprehensive review. This study aims to interconnect the fields of PAHs and graphenes, which have mainly been discussed separately. In particular, by selecting representative examples, we explain how these two domains can stimulate each other. We hope that this integrated approach can offer new opportunities and further promote synergistic developments in these fields. polycyclic aromatic hydrocarbon, graphene, graphene nanoribbon, nanographene, graphene quantum dot, carbon materials Citation: Wang XY, Yao X, Müllen K. Polycyclic aromatic hydrocarbons in the graphene era. Sci China Chem, 2019, 62: 1099–1144, https://doi.org/10.1007/ s11426-019-9491-2 1 Introduction conjugated polymer [3–10].
    [Show full text]
  • Electronic Coupling Effects and Charge Transfer Between Organic
    Institut fur¨ Angewandte Photophysik Fachrichtung Physik Fakult¨at Mathematik und Naturwissenschaften Technische Universit¨at Dresden Electronic Coupling Effects and Charge Transfer between Organic Molecules and Metal Surfaces Dissertation zur Erlangung des akademischen Grades Doktor der Naturwissenschaften (Doctor rerum naturalium) vorgelegt von Roman Forker geboren am 15. Mai 1981 in R¨ackelwitz Dresden 2010 Eingereicht am 15.09.2009 1. Gutachter: Prof. Dr. Karl Leo 2. Gutachter: Prof. Dr. Moritz Sokolowski Verteidigt am 12.01.2010 Abstract We employ a variant of optical absorption spectroscopy, namely in situ dif- ferential reflectance spectroscopy (DRS), for an analysis of the structure– properties relations of thin epitaxial organic films. Clear correlations between the spectra and the differently intense coupling to the respective substrates are found. While rather broad and almost structureless spectra are obtained for a quaterrylene (QT) monolayer on Au(111), the spectral shape resembles that of isolated molecules when QT is grown on graphite. We even achieve an efficient electronic decoupling from the subjacent Au(111) by inserting an atomically thin organic spacer layer consisting of hexa-peri-hexabenzocoronene (HBC) with a noticeably dissimilar electronic behavior. These observations are fur- ther consolidated by a systematic variation of the metal substrate (Au, Ag, and Al), ranging from inert to rather reactive. For this purpose, 3,4,9,10-perylene- tetracarboxylic dianhydride (PTCDA) is chosen to ensure comparability of the molecular film structures on the different metals, and also because its elec- tronic alignment on various metal surfaces has previously been studied with great intensity. We present evidence for ionized PTCDA at several interfaces and propose the charge transfer to be related to the electronic level alignment governed by interface dipole formation on the respective metals.
    [Show full text]