Massachusetts Institute of Technology, USA, 2011. – 138 p.Interfaces are ubiquitous in nature. From solidification fronts to the surfaces of biological cells, interfacial properties determine the interactions between a solid and a liquid. Interfaces, specifically liquid-solid interfaces, play important roles in many fields of science. In the field of biology, interfaces are fundamental in determining cell-cell interactions, protein folding behavior and assembly, and ligand binding. In chemistry, heterogeneous catalysts greatly increase reaction rates of reactions occurring at the interface. In materials science, crystallization and the resulting crystal habit are determined by interfacial properties, and interfaces affect diffusion through polycrystalline materials. In nanotechnology, much work on self-assembly, molecular recognition, catalysis, electrochemistry and numerous other applications depends on the properties of interfaces.
The structure and properties of interfaces have been studied experimentally using a variety of techniques including various forms of microscopy, wetting measurements, and scattering techniques. Conventionally, the typical interface considered was highly homogeneous and exhibited a uniform composition and roughness. In contrast, many of the interfaces encountered in biological or nanotechnological systems have surfaces with a greater degree of complexity. While the surface may be compositionally homogeneous over a large area, these surfaces are structured and have a complex surface topology. On a mixed interface, several different chemical groups may be present on the surface, and the chemical composition can vary on a sub-nanometer length scale
Contents Overview
Introduction to Interfacial Energy
Interfacial Energy of Patchy Surfaces
The Experimental Systems and Methods
Experimental Results
The Breakdown of Cassie-Baxter Theory and Considerations for a New Theory
Conclusions and Future Work
Appendix: Experimental Methods
