Multifunctional surfaces: hierarchical nanoarchitectures as a toolbox for complex reactions

For many decades scientists have been fascinated by the beauty and the complexity of nature and had the aim to create man‐made synthetic materials with all kinds of imaginable specific functionalities. In the field of biomimetics, smart surfaces play an important role. Towards their realization, functional polymer nanostructures were immobilized on a conductive metal
oxide surface through utilization of two different self‐assembly phenomena: metal‐ligand interactions and the formation of polymersomes from block copolymers. Glass supported titania surfaces were optimized in terms of surface roughness, by spin‐coating multiple layers of titania, and further modified by stepwise assembly of an [Fe(tpy)2]2+‐based complex as a linker unit to connect the polymersomes to the semiconductor surface. Nanoreactors based on aldehyde‐terminated poly(2‐methyloxazoline)‐block‐poly(dimethylsiloxane)‐block‐poly(2‐methyloxazoline) (PMOXA‐PDMS‐PMOXA) amphiphilic block copolymer were prepared and functionalized through Schiff base condensation with an amino‐functionalized tpy acting as an additional metal‐binding domain. These functionalized compartments were successfully immobilized on the tpy‐functionalized titania surface through assembly of the [Fe(tpy)2]2+ motif.
Chapter 1 gives a short overview over the strategy to create “smart surfaces” based on the immobilization of nanocompartments on a solid surface and introduces substrate types, appropriate linker systems and the formation of suitable nanocompartments with the corresponding immobilization techniques.
Chapter 2 describes the characterization of glass‐supported titania surfaces and their smoothing by application of multiple layers of spin‐coated titania.
Chapter 3 discusses surface modification by adsorption of metal‐binding domains and the optimization process for stepwise assembly of an [Fe(tpy)2]2+‐core as binding motif for polymersomes.
Chapter 4 describes polymersome formation and their subsequent functionalization with amino‐functionalized tpy units acting as a metal‐binding domains.
Chapter 5 shows the surface immobilization of the functionalized polymersomes.
Chapter 6 gives an overview of the methods and materials used in this thesis.
Chapter 7 concludes the thesis and gives a short outlook for the future.