عنوان المقالة: Metal-Conductive Polymer Core-Shell Nanowires: Electroless Reduction of Pd and Cu on Polypyrrole/DNA Templates Bearing 2-2’-Bipyridyl Groups
Mahdi Almaky* , Reda Hassanien , William Clegg , Ross Harrington , Andrew Houlton and Benjamin Horrocks
Abstract
A method for the preparation of conductive polymer nanowires bearing metal ion chelating 2,2’-bipyridyl
groups is described. N-(3-pyrrol-1-yl-propyl)-2,2'-bipyridinium hexafluorophosphate (NP2PBH) was templated
on λ-DNA in aqueous solution using FeCl3 as oxidant to initiate polymerization. The polyNP2PBH/DNA
nanowires were then decorated with metals (Cu or Pd) by electroless deposition [Cu(NO3)2/ascorbate or PdCl4
2-
/NaBH4]. UV-vis absorption spectra of the hybrid materials show the absorption peak due to the plasmon
resonance of Cu at about 550 nm and a broad continuous band consistent with metallic Pd in the range 300−700
nm. The morphology, size and electrical properties of the hybrid nanostructures have been characterized using
scanning probe techniques (atomic force microscopy (AFM), scanning conductance microscopy (SCM) and
conductive atomic force microscopy (cAFM)). The polyNP2PBH/DNA nanowires show a continuous, smooth
and uniform appearance (mean diameter 5.0 nm). Cu deposits on polyNP2PBH/DNA nanowires by a nucleation
and growth process that leads eventually to smooth, conductive Cu nanowires. In contrast, Pd deposits in a
non-uniform manner on polyNP2PBH/DNA and has inconsistent electrical conductivity. The electrical
conductivity of single Cu/polyNP2PBH/DNA nanowires was estimated to be 1.6 ± 0.27 S cm-1 which we suggest
is limited by electron transfer between Cu grains.
Publication Date
4/14/2020
Publisher
International Journal of Scientific Research in Science and Technology IJSRST
د. المهدي محمد المكي | Dr. Mahdi Mohammed Almaky | 8678