Nanostructured carbohydrate-derived carbonaceous materials [Elektronische Ressource] / Shiori Kubo. Betreuer: Markus Antonietti

Shiori Kubo

Informations

• Publié par: universitat_potsdam
• Publié le: 01 janvier 2011
• Nombre de lectures: 80
• Poids de l'ouvrage: 7 Mo

Extrait

Max-Planck-Institut
für Kolloid- und Grenzflächenforschung






Nanostructured Carbohydrate-Derived
Carbonaceous Materials









Dissertation


zur Erlangung des akademischen Grades
"doctor rerum naturalium"
(Dr. rer. nat.)
in der Wissenschaftsdisziplin "Physikalische Chemie"


eingereicht an der
Mathematisch-Naturwissenschaftlichen Fakultät
der Universität Potsdam




von
Shiori KUBO




Potsdam, den 16, 02, 2011













































Published online at the
Institutional Repository of the University of Potsdam:
URL http://opus.kobv.de/ubp/volltexte/2011/5315/
URN urn:nbn:de:kobv:517-opus-53157
http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-53157
Nanostructured Carbohydrate-Derived
Carbonaceous Materials

Shiori KUBO

Contents






1. Introduction..................................................................................................................... 1


2. Nanostructured Carbonaceous Materials ........................................................................ 7
2.1 Carbonisation Chemistry ...........................................................................................7
2.1.1 Classical Carbonisation (Pyrolysis)7
2.1.2 Hydrothermal Carbonisation...................................................................................9
2.2. Nanostructured Carbonaceous Materials ................................................................13
2.2.1 Activated Carbon ..................................................................................................14
2.2.2. Carbon Aerogels from the Carbonisation of Organic Aerogels...........................14
2.2.3. Carbon Aerogels from Biomass Derivatives .......................................................15
2.3 Nanocasting Methods...............................................................................................16
2.3.1. Soft Templating (endo-templating)......................................................................17
2.3.2. Hard Templating (exo-temp19


3. Characterisation Techniques......................................................................................... 21
3.1 Electron Microscopy................................................................................................21
3.1.1 Transmission Electron Microscopy (TEM) ..........................................................21
3.1.2 High Resolution Transmission Electron Microscopy (HR-TEM) ........................23
3.1.3 Scanning Electron Microscopy (SEM) .................................................................24
3.2 Small Angle X-ray Scattering (SAXS) ....................................................................26
3.3 Gas sorption .............................................................................................................31
3.3.1 Determination of surface area...............................................................................33
3.3.2 Assessment of Mesopore Size Distribution35
3.3.3 Assessment of Micr .........................................................36
3.3.4 Density Functional Theory (DFT) for Determination of Pore Chracteristics.......37
3.3.5. Quenched Solid Density Functional Theory (QSDFT) method ..........................38
3.4 Fourier Transform Infrared Spectroscopy (FTIR) ...................................................39


4. Hydrothermal Carbonisation of Carbohydrates in the presence of Inorganic Sacrificial
Templates.......................................................................................................................... 43
4.1. Introduction.............................................................................................................43 4.2. Silica as a Sacrificial Template...............................................................................46
4.2.1. Hard-Templating of Mesoporous Silica Beads for the Production of
Hydrothermal Carbon Sphere ....................................................................................46
4.2.2 Hydrothermal Carbon Monoliths..........................................................................53
4.3 Macroporous Alumina Membranes as a Sacrificial Template.................................56
4.3.1 Chemicals..............................................................................................................56
4.3.2 Synthesis ...............................................................................................................56
4.3.3 Results and Discussions........................................................................................58
4.4. Conclusion71


5. Hydrothermal Carbonisation of Carbohydrates in the presence of Block Copolymer
Templates.......................................................................................................................... 73
5.1. Introduction.............................................................................................................73
5.2 Experimental............................................................................................................75
5.2.1 Chemicals..............................................................................................................75
5.2.2 Synthesis ...............................................................................................................75
5.3 Selection of Structural Directing Agents .................................................................76
5.4 Effect of F127-Fru Composition..............................................................................80
5.5 Carbon Framework and Carbon Surface Functionalities.........................................86
5.6 Pore Size Control .....................................................................................................90
5.7 Further Optimisation of Synthesis Conditions.........................................................97
5.7.1 Effect of Carbon Source........................................................................................97
5.7.2 Synthesis temperature ...........................................................................................99
5.7.3 Addition of acid catalyst .....................................................................................100
5.7.4 Avoiding pore shrinkage102
5.8 Proposed Mechanism.............................................................................................104
5.8.1 F127 block copolymer in an aqueous solution ...................................................104
5.8.2 Formation of micelles in an aqueous carbohydrate solution...............................106
5.8.3 Formation of ordered block copolymer – hydrothermal carbon composite........107
5.9 Conclusion .............................................................................................................111


6. Conclusion and Outlook 113

Appendix......................................................................................................................... 117
A-1) Synthesis of PO -b-AA block copolymer .......................................................117 40 40
A-2) Calculation of carbon yield .................................................................................118
A-3) List of pore properties of the synthesised carbonaceous materials via soft
templating ....................................................................................................................118
A-4) Instrumental.........................................................................................................120
A-5) List of main abbreviations and symbols..............................................................123
A-6) Acknowledgement...............................................................................................125
A-7) References ...........................................................................................................127





























「人間は 考え る葦であ る。 」

Man is but a reed, the weakest of nature, but he is a thinking reed.

L'homme n'est qu'un roseau, le plus faible de la nature; mais c'est un roseau pensant.

- Blaise Pascal -











1. Introduction

From ancient times, society has made use of porous carbon materials; charcoal was used
1for decolourisation of alcohol, water and sugar in ancient Egypt. In Asian history, it has
1also been used as an adsorbent in order to protect religious shrines from moisture attack.
Today, porous carbon materials are widely used in industry as adsorbents (e.g. activated
carbon)