Synthesis of Conjugated Polymers and Adhesive Properties of Thin Films in OPV Devices

272 Pages·2015·23.06 MB·English

THÈSE
UNIVERSITE DE PAU ET DES PAYS DE L’ADOUR
École doctorale Science Exactes et Leurs Applications (ED211)

Soutenue le 12 Novembre 2015
par Alberto GREGORI

pour obtenir le grade de docteur
de l’Université de Pau et des Pays de l’Adour
Spécialité : Physico-Chimie de Polymères

Synthesis of Conjugated Polymers and Adhesive
Properties of Thin Films in OPV Devices

MEMBRES DU JURY

RAPPORTEURS
• Mme. Natalie STINGELIN Professeur, Imperial College London
• M. Markus C. SCHARBER Professeur, Johannes Kepler University Linz

EXAMINATEURS
• M. Paul D. TOPHAM Maitre de Conférence, Aston University Birmingham
• M. Patrice RANNOU Directeur de Recherche, CEA, CNRS, Université de Grenoble Alpes

DIRECTEURS
• Mme. Christine DAGRON-LARTIGAU Maitre de Conférence, HDR (superviseur), Université de Pau et des
Pays de l’Adour
• M. Ahmed ALLAL Professeur (co-superviseur), Université de Pau et des Pays de
l’Adour
• M. Roger C. HIORNS Chargé de Recherche, HDR (co-encadrant), CNRS, IPREM/EPCP, Pau

“It is sometimes a mistake to climb; it is always a mistake never even to make the attempt.
If you do not climb you will not fall. This is true. But is it that bad to fail, that hard to fall?
Sometimes you wake and, yes, sometimes you die.
But there is a third alternative.
(…) sometimes when you fall, you fly”

Fear of Falling - The Sandman, N. Gaiman

Acknowledgement
During these three years, I had the chance to meet and work many valuable researchers and
wonderfull human beings.
I would like to start thanking my family for having supported me all along my academic
studies. Then I have to thank my supervisor Christine, Ahmed and Roger, for entrusting me with the
freedom to conduct the experiment in my own way, without never let me miss their support and their
guidance in times of need.
Hussein, Hasina, Bruna, Hongyao, Edilene, Tonimar, Sebastien, Coralie, Julien, Mohamed,
Oscar, Rayane and all the other students at the IPREM for their help in the lab and their friendship,
which gave me the strength to overcome the darkest moments of these three years.
To all the Establis fellows a special thanks for the great scientifique exchanges and the partying
during our meeting. Hasina, Stefan, Simon, Isabel, Auré, Jenia, Jojo and Meera, I hope our friendships
will last for a long time.
To Mirella, Andi, Sebastian, Tobi, Sambatra, Bas, Bart, Mario, Christian, Michi, Hugo, Heike,
Kata and all the others I met at Belectric OPV go all my gratitude for the useful experience I had in
Nuremberg and I hope to see you all the next months.
Dani, Lorenzo and Juan meeting you was one of the best fluke of these past three years. Pau
would have not been the same without you. I’ll really miss you and it won’t be easy to find such great
friends as you.
Mask, Dani, Carla, Riccà, Lori, Ale, Fede, Luciano and Mauro thanks for making me feel less
homesick through your constant presence and friendship.
Last but not least, my deepest thankfulness goes to Mélanie and his family. For her support in
facing french administration, but mostly for having been such a precious friend and counselor from
the very first till the very end of my french chapter.

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Contents

Acknowledgement ..........................................................................................................................i
Contents ........................................................................................................................................ iii
List of Figures ............................................................................................................................... vii
List of Schemes ............................................................................................................................ xiii
List of Tables ................................................................................................................................ xiv
Glossary ........................................................................................................................................ xv
Abstract ...................................................................................................................................... xvii
Résumé ........................................................................................................................................ xix
1 Motivation and Background ................................................................................................... 1
1.1 Introduction ..................................................................................................................... 1
1.1.1 Current situation and the role of renewable sources ............................................... 2
1.1.2 Alternative energy and the contribution of renewable sources ............................... 4
1.1.3 Photovoltaics and Organic Photovoltaics ................................................................. 6
1.1.4 The ESTABLIS Project ................................................................................................. 7
1.1.5 Aim of the work ......................................................................................................... 9
1 Motivation et contexte ......................................................................................................... 13
1.1 Introduction ................................................................................................................... 13
1.1.1 Situation actuelle et rôle des sources d'énergie renouvelables ............................. 14
1.1.2 Energies alternatives et contribution des sources renouvelables .......................... 16
1.1.3 Photovoltaïque et photovoltaïque organique ........................................................ 18
1.1.4 Le projet ESTABLIS ................................................................................................... 20
1.1.5 Objectifs du travail .................................................................................................. 22
1.2 References ..................................................................................................................... 24

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2 Introduction .......................................................................................................................... 25
2.1 Brief history .................................................................................................................... 27
2.2 Working principle ........................................................................................................... 29
2.3 Device structures ........................................................................................................... 30
2.4 Parameters governing overall performance of solar cells ............................................. 32
2.5 Materials for the PhotoActive Layer .............................................................................. 35
2.5.1 Acceptor Materials ................................................................................................ 35
2.5.2 Donor materials .................................................................................................... 37
2.5.3 Polymerization Techniques ................................................................................... 38
2.6 References ..................................................................................................................... 47

3 Synthesis and Characterization of LBGs ............................................................................... 61
3.1 Π-Conjugated Silole-Based Polymers ............................................................................. 63
3.1.1 Silacyclopentadiene-Based Polymers ................................................................... 64
3.1.2 Dibenzosilole-Based Polymers .............................................................................. 65
3.1.3 Dithienosilole-Based Polymers ............................................................................. 66
3.2 Side-chain effect ............................................................................................................ 72
3.3 Synthesis and characterization of LBGs based on DTS and DPP Units .......................... 75
3.3.1 Introduction .......................................................................................................... 75
3.3.2 Synthesis of monomers ......................................................................................... 82
3.3.3 Polymer synthesis ................................................................................................. 83
3.3.4 Molecular weight and dispersity ........................................................................... 83
3.3.5 Optical properties ................................................................................................. 86
3.3.6 Electrochemical properties ................................................................................... 88
3.3.7 Thermal properties ............................................................................................... 90
3.4 Synthesis and characterization of LBGs Based on DTS and DTP Units .......................... 93
3.4.1 Introduction .......................................................................................................... 93
3.4.2 Monomer synthesis ............................................................................................. 101
3.4.3 Polymer synthesis ............................................................................................... 102
3.4.4 Molecular mass ................................................................................................... 103
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3.4.5 Optical Properties ............................................................................................... 105
3.4.6 Electrochemical Properties ................................................................................. 107
3.4.7 Thermal Properties ............................................................................................. 108
3.5 Conclusions .................................................................................................................. 109
3.6 References ................................................................................................................... 111

4 Application in Inverted Devices .......................................................................................... 119
4.1..Introduction ................................................................................................................. 121
4.2 Polymer:PC BM blend ratio and Solvent System ....................................................... 123
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4.3 Optimization of Active Layer Coating Temperature .................................................... 124
4.3.1 PSBDPP_C10C6:PC BM Based Devices .............................................................. 125
61
4.3.2 PSBDPP_C12:PC BM Based Devices .................................................................. 127
61
4.4 Effect of Additives on PSBDPP_C10C6:PC BM Based Devices ................................... 129
61
4.5 Spin-Coated Devices Under Inert Atmosphere............................................................ 131
4.6 Which is the limiting factor? ........................................................................................ 136
4.6.1 Hole mobility ....................................................................................................... 139
4.6.2 Morphology of the blends................................................................................... 140
4.6.3 Charge Carrier Recombination ............................................................................ 141
4.7 Conclusion .................................................................................................................... 144
4.8 References ................................................................................................................... 145

5 Mechanical Integrity of OPV Devices.................................................................................. 149
5.1..Introduction ................................................................................................................. 151
5.1.1 Classic Adhesion Models ..................................................................................... 154
5.1.2 Adhesion Testing Techniques ............................................................................. 158
5.1.3 Adhesion of Organic Electronics Materials ......................................................... 164
5.1.4 Adhesion in OPV’s Devices .................................................................................. 165
5.2 Results and Discussions ............................................................................................... 169
5.2.1 Pull-off Set Up Development .............................................................................. 169
5.2.2 New PEDOT:PSS Formulation .............................................................................. 174
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5.2.3 Block Copolymers as Adhesion-Enhancing Interlayers ....................................... 187
5.3 Conclusion .................................................................................................................... 195
5.4 References ................................................................................................................... 196

6 Conclusions ......................................................................................................................... 201

6 Conclusions ......................................................................................................................... 203

Annex 1 ..................................................................................................................................... 207

Annex 2 ..................................................................................................................................... 233

Annex 3 ..................................................................................................................................... 239

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