Fabrication of DNA-Templated Te and Bi2Te3 Nanowires by Galvanic Displacement

Abstract

This paper demonstrates the use of galvanic displacement to form continuous tellurium-based nanowires on DNA templates, enabling the conversion of metals, which can be deposited site-specifically, into other materials needed for device fabrication. Specifically, galvanic displacement reaction of copper and nickel nanowires is used to fabricate tellurium and bismuth telluride nanowires on λ-DNA templates. The method is simple, rapid, highly selective, and applicable to a number of different materials. In this study, continuous Ni and Cu nanowires are formed on DNA templates by seeding with Ag followed by electroless plating of the desired metal. These wires are then displaced by a galvanic displacement reaction where either Te or Bi2Te3 is deposited from an acidic solution containing HTeO2(+) ions or a combination of HTeO2(+) and Bi(3+) ions, and the metal wire is simultaneously dissolved due to oxidation. Both tellurium and bismuth telluride wires can be formed from nickel templates. In contrast, copper templates only form tellurium nanowires under the conditions considered. Therefore, the composition of the metal being displaced can be used to influence the chemistry of the resulting nanowire. Galvanic displacement of metals deposited on DNA templates has the potential to enable site-specific fabrication of a variety of materials and, thereby, make an important contribution to the advancement of useful devices via self-assembled nanotemplates.