IRG-II Highlight
One layer at a time
Figure: (a) Redox states of Prussian Blue. (b) Schematic of an (LPEI/PB)30 film swelling under the influence of an electric potential. |
What:
A research team led by Professors Christine Ortiz, Krystyn Van Vliet, and Paula Hammond of IRG-II have designed and characterized an electrochemically responsive polymer nanocomposite thin film with control over film thickness and mechanical properties. Specifically, they have used layer-by-layer assembly to create a thin film containing cationic linear poly(ethyleneimine) (LPEI) and anionic Prussian Blue (PB) nanoparticles.
So What:
Electrochemical control over the swelling and mechanical behavior of polymer nanocomposites is advantageous, in comparison with temperature or pH changes, in that it can be applied reversibly, rapidly, and locally (i.e., at an electrode instead of throughout the bulk). Moreover, the structure and function of biological molecules, cells, and organisms, for example, may be inadvertently altered by large changes in temperature or pH, whereas application of a small voltage maintains a comparatively mild environment.
Paper:
Electrochemically Controlled Swelling and Mechanical Properties of a Polymer Nanocomposite. Daniel J. Schmidt, Fevzi C. Cebeci, Z. Ilke Kalcioglu, Samantha G. Wyman, Christine Ortiz, Krystyn J. Van Vliet, and Paula T. Hammond. ACS Nano, Vol. 3(8), 2207–2216 (2009).
