200 nm

1. Electrochemical Processing of Nanoporous Structures for Superhydrophobic Materials and Polymer Imprinting Nikolay Dimitrov,SUNY Binghamton, DMR 0603019 E1 - Ag:Cu 4:1 E2 - Ag:Cu 1:1 200 nm EC - Ag:Cu 2:1 E3 - Ag:Cu 1:3 A new method for processing of nanoporous metallic materials is developed based upon a potential controlled displacement (PCD). In this method different applied potentials in a cementation like scenario enable control over the deposition to dissolution ratio. This in turn renders the surface roughness (porosity length scale) of the accordingly grown layer tunable. As seen from the above figure, a PCD protocol implemented in the “Cu dissolving - Ag plating” system allows for the synthesis of Ag nanoporous structures with fourfold difference in the porosity length scale. Electrochemical and STM surface analysis (insets) ascertain the surface limited redox replacement growth of epitaxial Ag-Cu multilayers at modulation thickness of 6-10 nm. Stripping of these structures shown in the figure below suggests sharp interlayer boundary manifested by a dealloying like behavior with critical potential that is strongly dependent upon the topmost layer thickness. It should be noted that this dealloying behavior is observed in a system with no miscibility over the entire range of compositions. A characterization work of the dealloying generated morphology is in progress. OPD 10 MLs Ag Pure Cu 10 Ag 20 Ag 30 Ag

2. Electrochemical Processing of Nanoporous Structures for Superhydrophobic Materials and Polymer Imprinting Nikolay Dimitrov,SUNY Binghamton, DMR 0603019 The major emphasis of this project since its beginning has been the collaborative effort. Joint research indeed warrants the success of the proposed work. This year we planned, organized and executed the visit of our graduate student Lasantha in Ian Wark Research Institute at UniSA - Adelaide, Australia. The main outcome here is manifested by (i) synthesizing a super-hydrophobic surface by PCD (as shown below), (ii) obtaining a trend in the contact angle as a function of the alloy composition and (iii) generating lot of fun for all of us who sponsored and participated in this endeavor. Kangaroo party View Out -Ian Wark Research Institute, University of South Australia (UniSA) SUPERHYDROPHOBIC View In – Lasantha (left) and his Jairo Garnica enjoy their characterization work in a clean room at Wark Broader Impact: The Australia Trip of Lasantha Viyannalage, July-August 2007 The surface of a silver layer grown by potential control displacement (PCD) on a copper substrate (upper); after an appropriate functionalization this layer becomes (lower)