Faculteit Wetenschappen Departement Chemie In-depth study of organophosphonic acid modification on titanium dioxide Proefschrift voorgelegd tot het behalen van de graad van Doctor in de Wetenschappen: Chemie aan de Universiteit Antwerpen, te verdedigen door Annelore Roevens Promotoren: Prof. dr. Vera Meynen Prof. dr. Frank Blockhuys Antwerpen, 2017 Table of contents List of Abbreviations .....................................................................................................1 General introduction .....................................................................................................3 Chapter 1 .........................................................................................................................7 1.1 Introduction ..........................................................................................................9 1.2 Organosilanes .....................................................................................................14 1.2.1 Synthesis and characteristics .....................................................................14 1.2.2 Material properties .....................................................................................20 1.2.3 Various supports .........................................................................................21 1.2.4 Stability.........................................................................................................22 1.2.5 Applications.................................................................................................23 1.3 Organophosphonic acids ..................................................................................25 1.3.1 Synthesis and characteristics .....................................................................25 1.3.2 Material properties .....................................................................................33 1.3.3 Various supports .........................................................................................35 1.3.4 Stability.........................................................................................................36 1.3.5 Applications.................................................................................................38 1.4 Grignard reagents ..............................................................................................41 1.4.1 Synthesis and characteristics .....................................................................41 1.4.2 Applications.................................................................................................43 1.5 Aim of this Ph.D.................................................................................................46 1.6 References ...........................................................................................................48 Chapter 2 .......................................................................................................................77 2.1 Experimental ......................................................................................................79 2.1.1 Materials .......................................................................................................79 2.1.2 Standard synthesis ..................................................................................... 79 2.1.3 Adsorption experiments ............................................................................ 80 2.1.4 Structural names ......................................................................................... 80 2.2 Characterization techniques ............................................................................ 82 2.3 Quantum chemical calculations ...................................................................... 87 2.4 References ........................................................................................................... 88 Chapter 3 ...................................................................................................................... 91 3.1 Introduction ....................................................................................................... 93 3.2 Results and discussion ...................................................................................... 96 3.2.1 Modification in water................................................................................. 96 3.2.2 Modification with toluene as the solvent .............................................. 113 3.3 Conclusions ...................................................................................................... 125 3.4 References ......................................................................................................... 127 Chapter 4 .................................................................................................................... 131 4.1 Introduction ..................................................................................................... 133 4.2 Results and discussion .................................................................................... 136 4.2.1 Solute–solvent interaction: modification with 3PA and PhPA in toluene ................................................................................................................. 136 4.2.2 Solvent–surface interaction: modification with 3PA and PhPA in water .................................................................................................................... 141 4.2.3 Effect of water and toluene on the reaction mechanism ..................... 145 4.2.4 The impact of solvent on the obtained surface properties ................. 147 4.3 Conclusion ........................................................................................................ 154 4.4 References ......................................................................................................... 155 Chapter 5 .....................................................................................................................159 5.1 Introduction ......................................................................................................161 5.2 Results and discussion ....................................................................................163 5.2.1 Isothermal titration calorimetry..............................................................163 5.3.2 Influence of the concentration .................................................................169 5.3.3 Influence of the type of organophosphonic acid ..................................174 5.3.4 Correlating the sorption experiments with synthesis .........................178 5.3 Conclusion ........................................................................................................181 5.4 References .........................................................................................................182 General conclusions and suggestions for future research ...................................187 General conclusion ............................................................................................187 Suggestions for future research .......................................................................191 Reference .............................................................................................................192 Summary .....................................................................................................................193 Samenvatting ..............................................................................................................199 List of publications ....................................................................................................205 Oral presentations at conferences............................................................................206 Poster presentations at conferences ........................................................................208 Received award ..........................................................................................................209 Dissertation supervision ...........................................................................................209 List of Abbreviations 1G Metyl Magnesium Bromide 1PA Methylphosphonic Acid 12PA Dodecylphosphonic acid 16PA Hexadecylphosphonic acid 18PA Octadecylphosphonic Acid 3PA Propylphosphonic Acid 8PA Octylphosphonic Acid BET Brunauer-Emmett-Teller CaHAP Calcium Hydroxyapaptite DFT Density Functional Theory DRIFT Diffuse Reflectance Infrared Fourier Transform IC Total Amount of Inorganic Carbon IR Infrared ITC Isothermal Titration Calorimetry ITO Indium Tin Oxide PA Organophosphonic Acid PAW Projector Augmented Wave PBC Periodic Boundary Conditions PEG Polyethylene Glycols List of Abbreviations | 1 PhG Phenyl Magnesium Bromide PhPA Phenylphosphonic Acid PS Polystyrene 31P- CP/MAS NMR Phosphorus-31 Solid-State Cross-Polarization Magic Angle Spinning Nuclear Magnetic Resonance QE Quantum Espresso SAM Self-Assembled Monolayer SEM EDX Scanning Electron Microscope with Energy Dispersive X-ray Spectrometry T-BAG Tethering by Aggregation and Growth TC Total Amount of Carbon TGA Thermogravimetric Analysis TiP Titanium Organophosphonate TiPhP Titanium Phenylphosphonate TiPP Titanium Propylphosphonate TOC Total Organic Carbon 2 General introduction The use of materials in a specific application is strongly dependent of the physico-chemical properties of the materials. Metal oxides generally exhibit a high chemical stability. Furthermore, their properties can be steered depending