Electroless synthesis of 3 nm wide alloy nanowires insideTobacco mosaic virus

Abstract

We show that 3 nm wide cobalt-iron alloy nanowires can be synthesized by simple wet chemical electroless deposition inside tubular Tobacco mosaic virus particles. The method is based on adsorption of Pd(II) ions, formation of a Pd catalyst, and autocatalytic deposition of the alloy from dissolved metal salts, reduced by a borane compound. Extensive energy-filtering TEM investigations at the nanoscale revealed that the synthesized wires are alloys of Co, Fe, and Ni. We confirmed by high-resolution TEM that our alloy nanowires are at least partially crystalline, which is compatible with typical Co-rich alloys. Ni traces bestow higher stability, presumably against corrosion, as also known from bulk CoFe. Alloy nanowires, as small as the ones presented here, might be used for a variety of applications including high density data storage, imaging, sensing, and even drug delivery.

A Genetically Modified Tobacco Mosaic Virus that can Produce Gold Nanoparticles from a Metal Salt Precursor

“…While unmodified TMV can actively bind metal ions via its surface exposed exterior OH and COOH groups, and also through its accessible OH and primary amine groups on the interior channel, these do not efficiently reduce the sequestered ions into metal nanoparticles or result in metallization of the virus (which is consistent with our data and that of other labs). For production of metallized TMV for a multitude of different applications (such as components in circuitry, batteries and fuel cells; Royston et al, 2008 ; Gerasopoulos et al, 2010 ), the metal ions sequestered by TMV have previously been reduced into metal via exposure to exogenous reducing chemicals ( Shenton et al, 1999 ; Knez et al, 2004 ; Balci et al, 2006 , 2012 ; Love et al, 2014 ). Interestingly it has previously been observed that the reducing conditions can be easily modulated to favor the deposition of very small ∼5 nm discrete gold metal nanoparticles on the surface of WT TMV, rather than complete surface metallization ( Kobayashi et al, 2011 , 2012 ).…”

Bio-inspired synthesis of metal nanomaterials and applications

“…Viruses usually provide binding sites for metal ions and nucleation sites for MNMs formation with or without the need of additional reducing agents. 112,115 Balci et al 117 also demonstrated an electroless synthesis of 3 nm wide CoFe alloy NWs (Fig. A proposed strategy deals with the activation of viral surfaces for enhanced nucleation.…”

Tobacco mosaic virus: A biological building block for micro/nano/bio systems

“…The exterior surface and/or the central channel of TMV has been selectively metallized using electroless deposition (ELD). [47][48][49][50][51][52][53][54][55][56][57] ELD is advantageous for biological structures since they cannot be contacted electrically; therefore, electrodeposition cannot be utilized. In addition, ELD usually provides uniform coating even on high-aspect ratio structures including nanoscale elements.…”