Date: Thursday, June 9, 2016
Time: 11:00 am
Speaker: Ozgur Sahin, Columbia University
Title: Microbe-Powered Machines: Harnessing Water Confinement in Biological Nanostructures
Location: 67-3111 Chemla Room
Plants and many other biological organisms have developed structures that are extraordinarily effective in harnessing spatial and temporal changes in relative humidity to actuate structural changes. It is surprising that structures and devices made by humans rarely, if ever, take advantage of this powerful and apparently reliable phenomenon. Working with spores of Bacillus as a model system, and using the atomic force microscopy platform, we study water behavior in biological structures, particularly the behavior under nanoscale confinement. Confinement endows water with the ability to convert energy from changes in relative humidity with high efficiency. In this talk, I will present our recent work on the energy conversion process in spores. We found that spores can act like muscles that generate mechanical work with energy densities exceeding synthetic actuators. The effectiveness of spores inspired us to develop spore-based hybrid materials that change shape dramatically in response to changing humidity. We then used these hybrid materials to create macroscopic evaporation-driven engines that can generate power when placed above water, in a sub-saturated atmosphere.