Electrodeposition of molybdenum dioxide (using the step edges of highly oriented pyrolytic graphite as nucleation templates) is used to form precursor nanowires ranging in diameter from 10 nm to one micron with many exceeding one-half millimeter in length. Subsequent treatment with hydrogen gas above 500°C reduces the wires to conductive metallic molybdenum. (Science, December 15, 2000, 290 (5499) 2120, selected as cover story). Currently, this is the only method which exists to create millions of ordered nanowire arrays with such high aspect ratios. A film of either polystyrene or cyanoacrylate polymer is used to lift the wires off of the conductive graphite substrate making electronically isolated wires. Electronically isolated wires such as these hold promise to be sensors, electronic interconnects or as precursors for growing more complex electrodeposited circuitry.

The discovery of a method to deposit nanowires is just the beginning. By using a piece of a double-sided copper-clad circuit board as a support, the polymer containing nanowires can be made into a robust sensor device.