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Processing Graphene Oxide and Carbon Nanotubes: Routes to Self- Assembly of Designed Architectures for Energy Storage Applications

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Processing Graphene Oxide and Carbon Nanotubes: Routes to Self- Assembly of Designed Architectures for Energy Storage Applications University of Wollongong Research Online University of Wollongong Thesis Collection 1954-2016 University of Wollongong Thesis Collections 2014 Processing graphene oxide and carbon nanotubes: routes to self- assembly of designed architectures for energy storage applications Seyed Hamed Aboutalebi University of Wollongong Follow this and additional works at: https://ro.uow.edu.au/theses University of Wollongong Copyright Warning You may print or download ONE copy of this document for the purpose of your own research or study. The University does not authorise you to copy, communicate or otherwise make available electronically to any other person any copyright material contained on this site. You are reminded of the following: This work is copyright. Apart from any use permitted under the Copyright Act 1968, no part of this work may be reproduced by any process, nor may any other exclusive right be exercised, without the permission of the author. Copyright owners are entitled to take legal action against persons who infringe their copyright. A reproduction of material that is protected by copyright may be a copyright infringement. A court may impose penalties and award damages in relation to offences and infringements relating to copyright material. Higher penalties may apply, and higher damages may be awarded, for offences and infringements involving the conversion of material into digital or electronic form. Unless otherwise indicated, the views expressed in this thesis are those of the author and do not necessarily represent the views of the University of Wollongong. Recommended Citation Aboutalebi, Seyed Hamed, Processing graphene oxide and carbon nanotubes: routes to self- assembly of designed architectures for energy storage applications, Doctor of Philosophy thesis, Australian Institute for Innovative Materials, University of Wollongong, 2014. https://ro.uow.edu.au/theses/4126 Research Online is the open access institutional repository for the University of Wollongong. For further information contact the UOW Library: [email protected] Australian Institute for Innovative Materials (AIIM) Institute for Superconducting and Electronic Materials (ISEM) Processing Graphene Oxide and Carbon Nanotubes: Routes to Self- Assembly of Designed Architectures for Energy Storage Applications Seyed Hamed Aboutalebi The thesis is submitted in fulfilment of the requirements for the Award of the Degree of Doctor of Philosophy University of Wollongong Feb 2014 Declaration I, Seyed Hamed Aboutalebi, declare that this thesis, submitted in fulfilment of the requirements for the award of Doctor of Philosophy, at the Australian Institute for Innovative Materials, University of Wollongong, is wholly my own work unless otherwise referenced or acknowledged. The document has not been submitted for qualification at any other academic institution. Seyed Hamed Aboutalebi Feb, 2014 i This work is dedicated to my parents, Mrs. Fatemeh Mazloum and Mr. Seyed Esfandiyar Aboutalebi for their unconditional love and support through all stages of my life. ii Table of Contents Declaration ........................................................................................................................................... i List of Figures .......................................................................................................................................... 6 Abstract ................................................................................................................................................. 21 Acknowledgement ................................................................................................................................ 23 Chapter 1: Introduction ........................................................................................................................ 25 Chapter 2: Literature Review ................................................................................................................ 27 2.1 Energy Storage ............................................................................................................................ 27 2.2 Structure of Electrochemical supercapacitors (ECs) ................................................................... 32 2.3. Supercapacitors: Basics .............................................................................................................. 34 2.3.1. Capacitance measurements ................................................................................................ 34 2.3.2 Energy density ...................................................................................................................... 34 2.3.3 Power density ...................................................................................................................... 35 2.3.4 Cycle life ............................................................................................................................... 35 2.3.5 Measurements for systems based on two-electrode configuration ................................... 35 2.4 Classification of Supercapacitors ................................................................................................ 36 2.4.1 Pseudo-capacitors ................................................................................................................ 36 2.4.2 Electrochemical double layer capacitors (EDLCs) ................................................................ 38 2.5. The choice of Active Materials for EDLCs .................................................................................. 41 2.6. Graphene for EC applications: a brief history ............................................................................ 44 2.7. Graphene: structure ................................................................................................................... 45 2.8. But what is a 2D crystal? ............................................................................................................ 47 2.9. Graphene oxide: a brief history ................................................................................................ 48 2. 10. Graphene oxide: structure ...................................................................................................... 49 2.11. But why GO instead of graphene? ........................................................................................... 52 2.12 References ................................................................................................................................ 54 Chapter 3: Scope of the thesis .............................................................................................................. 62 3.1 Motivation ................................................................................................................................... 62 3.2 References .................................................................................................................................. 66 Chapter 4: Experimental section ........................................................................................................... 68 4.1 Synthesis of liquid crystalline graphene oxide (LC GO) ............................................................... 68 Synthesis of MWCNT-GO hybrid composites ................................................................................... 69 1 4.2 Layer-by-layer self-assembly of the LC GO-SWNT composite .................................................... 69 4.3 GO-SWNT hybrid synthesis in CHP .............................................................................................. 70 4.4 Characterization .......................................................................................................................... 70 4.5 Wet-spinning of GO and rGO fibers and yarns ........................................................................... 71 4.6 Characterization of fibers............................................................................................................ 72 4.7 Raman and Rheological characterization.................................................................................... 72 4.8Supercapacitor measurements for MWCNT-GO hybrid composites ........................................... 73 4.9 Hydrogen uptake measurements ............................................................................................... 74 4.10 Supercapacitor measurements ................................................................................................. 74 4.11 References ................................................................................................................................ 76 Chapter 5: Comparison of GO, GO/MWCNTs composite and MWCNTs as potential electrode materials for supercapacitors ............................................................................................................... 77 5.1 Supercapacitors........................................................................................................................... 77 5.2 GO and hybrid materials of GO-MWCNTs supercapacitors ........................................................ 78 5.3 Structural characterization ......................................................................................................... 79 5.3.1 XRD ....................................................................................................................................... 79 5.3.2 XPS .......................................................................................................................................
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