Nanoscopic studies of conjugated polymer blends by (electric) scanning probe microscopy [Elektronische Ressource] / Ling Sun

Ling Sun

Informations

• Publié par: johannes_gutenberg-universitat_mainz
• Publié le: 01 janvier 2010
• Nombre de lectures: 9
• Langue: English
• Poids de l'ouvrage: 8 Mo

Extrait

Nanoscopic Studies of Conjugated Polymer Blends
by (Electric) Scanning Probe Microscopy



Dissertation
zur Erlangung des Grades
“Doktor der Naturwissenschaften”
im Promotionsfach Chemie

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


Ling Sun (M.Sc.)
geboren in Liaoning, V. R. China


Mainz, 2010







Tag der mündlichen Prüfung: 28. 06. 2010





Table of Contents

Table of Contents


Abstract ........................................................................................................................ 1
Introduction ................. 3
Motivation .................... 9
Outline ......................... 11

Chapter 1 Scanning Probe Microscopy Techniques ............................................... 13
1.1 Scanning tunneling microscopy ..................................................... 13
1.2 Atomic force microscopy ................................ 13
1.2.1 Introduction ............................................ 14
1.2.2 Imaging modes ....................................... 14
1.3 Conductive atomic force microscopy ............................................ 16
1.3.1 Contact mode c-AFM ............................................................................................ 16
1.3.2 Scanning conductive torsion mode microscopy ..................... 17
1.4 Kelvin probe force microscopy ...................... 19
1.4.1 Basic principles of KPFM ................................................................ 19
1.4.2 Detection of V ................................... 22 CPD
1.4.3 Detection of F ..................................................................... 24 2 ω

Chapter 2 Materials and Sample Preparations ...................... 25
2.1 Materials .......................................................................................................................... 25
2.1.1 Gold nanoparticles ................................. 25
2.1.2 PPy:PSS ................. 26
2.1.3 Ag core-shell particles ........................................................................................... 27
2.1.4 Au bulk particles .................................... 28
2.2 Sample preparations ....................................................................... 28
2.2.1 Individual AuNPs and Au clusters ......... 28
2.2.2 HOPG substrate and HOPG sample ...................................... 31
2.2.3 Thick PPy:PSS films .............................................................................................. 31
2.2.4 Thin PPy:PSS films ............................... 31
2.2.5 Thin PSSH films .................................... 32
2.2.6 Design of electrode array ....................................................................................... 32
2.2.7 Two geometries of electrode array ......... 33
2.2.8 Pt electrodes for contact resistance test .................................................................. 35

Chapter 3 Nanoelectronic Properties of a Model System ...... 37
3.1 Introduction ..................................................................................................................... 37
3.2 Experimental ................... 37
3.2.1 Phase measurement ................................................................................................ 37
3.2.2 KPFM measurement .............................. 38
I Table of Contents
3.2.3 SCTMM measurement ........................................................................................... 39
3.3 KPFM and SCTMM studies on Au/PS model system .................. 40
3.3.1 Phase analysis of individual AuNPs ....................................................................... 40
3.3.2 KPFM analysis of individual AuNPs ..... 42
3.3.3 SCTMM analysis of individual AuNPs .. 47
3.3.4 KPFM and SCTMM analyses of Au clusters ......................................................... 52
3.3.5. Influence of SCTMM measurement on KPFM measurement ............................... 56
3.5. KPFM and SCTMM studies on PPy:PSS films ........................... 57
3.6 Summary and Conclusions ............................................................................................. 59

Chapter 4 Nanoscopic Topography and Dielectric Constants of PPy:PSS Films
upon Humidity ........................................................................................................... 61
4.1 Introduction ..................... 61
4.2 Experimental ................... 61
4.2.1 Dielectric constant characterization by KPFM ...................... 61
4.2.2 KPFM measurement in controlled humidity .......................................................... 62
4.2.3 Types of samples .................................................................... 63
4.3 Thick PPy:PSS films ....................................... 64
4.3.1 Influence of humidity on unannealed PPy:PSS ...................................................... 64
4.3.2 Influence of humidity on annealed PPy:PSS .......................... 66
4.4 Thin PPy:PSS films ......................................................................................................... 68
4.4.1 Influence of RH on the topography of unannealed PPy:PSS . 68
4.4.2 Influence of RH on dielectric constants of unannealed PPy:PSS ........................... 71
4.4.3 Influence of RH on annealed PPy:PSS................................................................... 75
4.5 Reference tests ................................................. 77
4.5.1 Influence of RH on freshly cleaved HOPG ............................ 77
4.5.2 Influence of RH on unannealed thin PSSH films ................................................... 78
4.6 Summary and conclusions .............................................................. 80

Chapter 5 Nanoscopic Conductivity Measurement of Single Particles ................ 81
5.1 Introduction ..................................................................................................................... 81
5.2 Experimental ................... 81
5.2.1 Macroscopic four-point probe method ................................................................... 81
5.2.2 Microscopic four-point probe measurement .......................... 82
5.2.3 EDX measurement on Ag core-shell particles ....................................................... 82
5.3 Results and discussion ..................................................................... 83
5.3.1 Conductivity measurement of Ag core-shell particles ............ 83
5.3.2 Conductivity measurement of Au bulk particles .................................................... 87
5.3.3 Conductivity measurement of FIB deposited Pt electrodes ................................... 88
5.4 Summary and conclusions .............................................................. 89

Chapter 6 Concluding Remarks ............................................... 91
6.1 Summary and conclusions .............................................................. 91
6.2 Outlook ............................................................. 93
II Table of Contents
Acknowledgments .......................................................... Error! Bookmark not defined.
Symbols and Abbreviations ...................................................... 97
Appendix .................................................................................. 101
Bibliography ............ 107
Curriculum Vitae............................................................ Error! Bookmark not defined.


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