UW-Stevens Point, Chemistry, Stevens Point, WI 54481
New applications in clean energy, electronics, and biotechnology are likely to require the use of novel, nanostructured materials, manufactured through economical and environmentally friendly techniques. One such technique, which can be used to mass-produce metal and semiconductor nanowires of a variety of shapes, sizes, and chemical compositions, is Electroplate-and-Lift (E&L) Lithography. E&L has been developed jointly by students at UW-Stevens Point and scientists at Argonne National Laboratory, and is a fast and simple technique. In E&L, wires are electrochemically deposited on a reusable electrode made of ultrananocrystalline diamond (UNCD)TM. An advantage of making templates from UNCD is that it is chemically stable over a very wide range of electrochemical potentials – a far wider range than other types of electrodes, and wider than the water-based solutions from which metals are often electroplated. The robust nature of UNCD electrodes may enable the deposition of highly reactive metals which require non-aqueous, ionic liquid electrolytes. Ionic liquids are salts which are liquid at or near room temperature, stable at a range of voltages at which water decomposes, and able to dissolve many metals which are water-reactive as well as metals which are water-stable. UNCD templates will allow the entire electrochemical potential window of many ionic liquids to be explored. This may lead to both the creation of nanowires of aqueous-electroplatable metals under previously inaccessible voltage conditions, and allow the electroplating and E&L patterning of wires made of water-reactive materials. In the present work, preliminary data is presented for the electrodeposition of iron nanowires on E&L templates. Iron has previously been deposited from ionic-liquid solutions in bulk electroplating systems, where its behavior is well understood. This makes iron a good model system for the study of electrodeposition from ionic liquids on UNCD templates, with a future goal of depositing wires that would otherwise be impossible to make using other benchtop methods.
[Abstract (DOCX)]