title: Smooth and conductive DNA-templated Cu₂O nanowires: growth morphology, spectroscopic and electrical characterization.
abstract: DNA strands have been used as templates for the self-assembly of smooth and conductive cuprous oxide (Cu₂O) nanowires of diameter 12-23 nm and whose length is determined by the template (16 μm for λ-DNA). A combination of spectroscopic, diffraction and probe microscopy techniques showed that these nanowires comprise single crystallites of Cu₂O bound to the DNA molecules which fused together over time in a process analogous to Ostwald ripening, but driven by the free energy of interaction with the template as well as the surface tension. Electrical characterization of the nanowires by a non-contact method, scanned conductance microscopy and by contact mode conductive AFM showed the wires are electrically conductive. The conductivity estimated from the AFM cross section and the zero-bias conductance in conductive AFM experiments was 2.2-3.3 S cm⁻¹. These Cu₂O nanowires are amongst the thinnest reported and show evidence of strong quantum confinement in electronic spectra.
authors.affiliation: Chemical Nanoscience Laboratory, School of Chemistry, Bedson Building, Newcastle University, Newcastle upon Tyne NE1 7RU, UK.
authors.forename: Reda
authors.initials: R
authors.lastname: Hassanien
authors.forename: Said A Farha
authors.initials: SA
authors.lastname: Al-Said
authors.forename: Lidija
authors.initials: L
authors.lastname: Siller
authors.forename: Ross
authors.initials: R
authors.lastname: Little
authors.forename: Nicholas G
authors.initials: NG
authors.lastname: Wright
authors.forename: Andrew
authors.initials: A
authors.lastname: Houlton
authors.forename: Benjamin R
authors.initials: BR
authors.lastname: Horrocks
mesh_terms: D010582:Bacteriophage lambda / Q000737:chemistry*; D003300:Copper / Q000737:chemistry*; D004279:DNA, Viral / Q000737:chemistry*; D004553:Electric Conductivity; D018625:Microscopy, Atomic Force; D053770:Nanowires / Q000737:chemistry* / Q000648:ultrastructure*; D013057:Spectrum Analysis
chemical_list: D004279:DNA, Viral; D003300:Copper; C000520:cuprous oxide