- Mathematik Hydrophobic Nanoreactor Templating for Nanostructured Metal - Tin-rich ITO Materials vorgelegt von M.Sc. Amandine Guiet Geb. in Angers, Frankreich Von der Fakultat II und Naturwissenschaften dertechnischen Universitat Berlin zur Erlangung des akademischen Grades Doktor der Naturwissenschaften Dr. rer. nat. genehmigte Dissertation Promotionsausschuss: Vorsitzender: Prof. Dr. rer. nat. Marga Lensen Gutachter: Prof. Dr. rer. nat. Arne Thomas Prof. Dr. rer. nat. Christina Roth Dr. rer. nat. Anna Fischer Tag der wissenschaftlichen Aussprache: 12. Juni 2014 Berlin 2014 D83
TABLE OF CONTENT 1 INTRODUCTION 14 1.1 Motivation/Aim of the work 14 1.2 Transparent conducting oxides (TCO) 18 1.2.1 Theoretical background of TCO materials 18 1.2.2 Electrical and optical properties of TCO materials 19 1.3 Immobilization of NPs into nanostructured metal oxides 20 1.3.1 Immobilization of NPs into mesoporous metal oxides 20 1.3.2 Encapsulation of NPs into yolk-shell structure 26 1.4 Single source precursor approach for a new alternative to ITO 29 1.4.1 Indium(l) tin(ll) tris-te/t-butoxide (ITBO) as single-source precursor 30 1.4.2 Single-source molecular approach for synthesis of ITOTR thin film 33 1.5 Experimental section 35 1.5.1 Synthesis of indium(l) tin(ll) tris-rerr-butoxide (ITBO) 35 1.5.2 Preparation of planar ITOTR thin films 37 2 CHARACTERIZATION METHODS 38 2.1 Electron microscopy 38 2.1.1 Fundamentals 38 2.1.2 Electron-matter interactions 39 2.1.3 Transmission electron microscopy (TEM) 41 2.1.4 Scanning electron microscopy (SEM) 43 2.1.5 Energy dispersive X-ray spectroscopy (EDX) 44 2.2 X-rays scattering 44 2.2.1 Fundamentals 44 2.2.2 Small Angle X-ray Scattering (SAXS) 46 2.2.3 Anomalous Small Angle X-ray Scattering (ASAXS) 49 2.2.4 Wide Angle X-ray Scattering (WAXS) 50 2.3 X-ray absorption (XAS) 51 8
2.4 Gas physisorption 53 2.4.1 Gas sorption isotherms 53 2.4.2 Specific surface area determination 54 2.5 Characterization of electrical conductivity 55 2.6 Dynamic light scattering (DLS) 56 2.7 Instrumental details 58 2.7.1 NMR spectroscopy 2.7.2 UV-vis spectroscopy 58 58 2.7.3 Thermogravimetric analysis (TGA) 58 2.7.4 Dynamic Light Scattering (DLS) 58 2.7.5 X-Ray Diffraction (XRD) 58 2.7.6 Small-Angle X-ray Scattering (SAXS) 58 2.7.7 X-ray absorption near edge spectroscopy (XANES) 59 2.7.8 Electron microscopy 60 2.7.9 Conductivity measurements 61 2.7.10 X-ray photoelectron spectroscopy (XPS) 61 3 PS-B-P4VP INVERSE MICELLES AS HYDROPHOBIC TEMPLATE 62 3.1 Introduction 62 3.2 Nanostructuration of ITOTR with traditional block copolymer as template 63 3.3 Nanostructuration of ITOTR with preformed PSm-b-P4VP micelles as hydrophobic template 65 3.3.1 Synthesis and characterization of PSm-b-P4VPn block copolymer 65 3.3.2 Formation of PS111-i-P4VP96 inverse micelles 68 3.3.3 PS-fe-P4VP inverse micelles as versatile template for ITOTRoxide 72 3.4 Conclusion 78 3.5 Experimental section 80 3.5.1 Materials 80 3.5.2 Preparation of mesoporous ITOTR thin films with F127 block copolymer as template 80 3.5.3 Synthesis of mesoporous ITOTR thin films via hydrophobic templating strategy 80 9
4 PS-A-P4VP INVERSE MICELLES AS NANOCONTAINER TEMPLATE 82 4.1 Introduction 82 4.2 Gold loaded PSm-b-P4VPn micelles as hydrophobic nanocontainer template 83 4.3 Preparation of mp-itotr loaded with one AuNP per pore 86 4.4 Electrochemical applications of mp-aunp-itotr electrodes 90 4.4.1 Immobilization of small molecules 90 4.4.2 Electrocatalytic CO oxidation 92 4.5 Conclusion 94 4.6 Experimental section 95 4.6.1 Synthesis of mesoporous ITOTR thin films with one Au NP per pore 95 4.6.2 Synthesis of AuNP 2D-arrays on ITO (AuNP-ITO) via micelle nanolithography 95 4.6.3 Electrochemical Measurements 95 5 PS-B-P4VP INVERSE MICELLES AS NANOREACTOR TEMPLATE 98 5.1 Increase of the gold loading 98 5.2 From open pore to yolk-shell structure 104 5.2.1 Preliminary results 104 5.2.2 Formation mechanism of hybrid HAuCI4@lnxSnv02 core-shell micelles in solution 105 5.2.3 Characterization of AuNPs@ITOTR yolk-shell based tin films 115 5.2.4 Formation of the AuNPs 121 5.2.5 Thermal stability of the NPs 125 5.2.6 Influence of the synthetic parameters 128 5.3 Conclusion 136 5.4 Experimental section 139 5.4.1 Materials 139 5.4.2 PSm-fa-P4VPn characteristics 139 5.4.3 Synthesis of AuNPs@ITOTRyolk-shell based thin films with spherical structure 139 5.4.4 Synthesis of AuNPs@ITOTRyolk-shell based thin films with wormlike structure 140 10
6 HYDROPHOBIC NANOREACTOR TEMPLATING: A VERSATILE SYNTHETIC TOOLBOX FOR A VARIETY OF YOLK-SHELL MATERIALS 142 6.1 Preparation of PtNPs@ITOTRyolk-shell materials 142 6.1.1 Introduction 142 6.1.2 Platinum loaded PSm-b-P4VPn micelles 143 6.1.3 Synthesis of PtNPs@ITOTRyolk-shell based thin films 146 6.1.4 Conclusion 152 6.2 Preparation of bimetallic NPs@ITOTR yolk-shell materials 154 6.2.1 Preparation of AgAuNPs@ITOTR yolk-shell materials 155 6.2.2 Preparation of AuPtNPs@ITOTR yolk-shell materials 166 6.3 Experimental section 180 6.3.1 Materials 180 6.3.2 PSm-b-P4VPn characteristics 180 6.3.3 Synthesis of PtNPs@ITOTR yolk-shell materials with spherical or wormlike structure 180 6.3.4 Synthesis of AgAuNPs@ITOTR yolk-shell materials with spherical 6.3.5 Synthesis of AuPtNPs@ITOTRyolk-shell materials with spherical structure 182 structure 182 7 CONCLUSION AND OUTLOOK 184 8 APPENDIX 186 9 PUBLICATION LIST 188 10 ACKNOWLEDGMENT 190 11 REFERENCES 192 11