Prof. Rubner to give Wulff Lecture, Nov. 17
Nature Inspired Materials Science
Prof. Michael Rubner
Nov. 17, 4:00, 10-250
Reception to follow in the Bush Room, 10-105
Materials Scientists more and more are looking to nature for clues on how to create highly functional materials with exceptional properties. The fog harvesting capabilities of the Namib Desert beetle, the beautiful iridescent colors of the hummingbird, and the super water repellant abilities of the Lotus leaf are but a few examples of the amazing properties developed over many years in the natural world. Nature also makes extensive use of the pH-dependent behavior of weak functional groups such as carboxylic acid and amine functional groups. The pH-gated opening and closing of the carboxylate-lined cages of the cowpea chlorotic mottle virus, for example, is an important element of the infection process. This presentation will explore synthetic mimics to the nano- and microstructures responsible for these fascinating properties. For example, we have demonstrated a pH-induced porosity transition that can be used to create porous films with pore sizes that are tunable from the nanometer scale to the multiple micron scale. The pores of these films, either nano- or micropores, can be reversibly opened and closed by changes in solution pH. The ability to engineer pH-gated porosity transitions in heterostructure thin films has led to the demonstration of broadband anti-reflection coatings that mimic the anti-reflection properties of the moth eye and pH-tunable Bragg reflectors with a structure and function similar to that found in hummingbird wings. In addition, the highly textured honeycomb-like surfaces created by the formation of micron-scale pores are ideally suited for the creation of superhydrophobic surfaces that mimic the behavior of the self-cleaning lotus leaf. Techniques to create patterned superhydrophobic/superhydrophilic surfaces have also been developed that make it possible to create planar open microfluidic channels as well as fog-harvesting coatings that mimic the behavior of the Namib Desert beetle.
The Wulff Lecture is an introductory, general-audience, entertaining lecture which serves to educate, inspire, and encourage MIT undergraduates to take up study in the field of materials science and engineering and related fields. The entire MIT community is invited to attend. The Wulff Lecture honors the late Professor John Wulff, a skilled, provocative, and entertaining teacher who inaugurated a new approach to teaching the popular freshman subject: 3.091 Introduction to Solid State Chemistry.
Tags: Rubner
