Nanowire surface chemistry

The enormous surface to volume ratio of the nanowires profoundly impacts the nanowire properties, making it imperative to control the surface chemistry. Several chemical routes have been explored for passivating or functionalizing nanowire surfaces. Hanrath and Korgel reported a comprehensive investigation of Ge nanowire surface chemistry modification including oxidation, sulfidation, hydride and chloride termination, and organic monolayer passivation... 

Chan C. K., Ruffo R., Hong S. S., Cui Y. Surface chemistry tmd morphology of the solid electrolyte interphase on silicon nanowire Uthium-ion battery anodes, J. Power Sources 2009, 189,1132-1140. 

This chapter summarizes the main theoretical approaches to model the porous silicon electronic band structure, comparing effective mass theory, semiempirical, and first-principles methods. In order to model its complex porous morphology, supercell, nanowire, and nanocrystal approaches are widely used. In particular, calculations of strain, doping, and surface chemistry effects on the band structure are discussed. Finally, the combined use of ab initio and tight-binding approaches to predict the band structure and properties of electronic devices based on porous silicon is put forward. 

Petretto G, Debemardi A, Fanciulli M (2012) Electronic properties of pristine and Se doped [001] silicon nanowires an ab initio study. J Nanosci Nanotechnol 12 8704-8709 Puzder A, Williamson AJ, Grossman JC, Galli G (2002a) Surface chemistry of silicon nanoclusters. Phys Rev Lett 88(9) 097401... 

Etacheri V, Haik O, Goffw Y, Roberts GA, Stefan IC, Fasching R, Aurbach D (2012) Effect of fiuoroethylene carbonate (FEC) on the performance and surface chemistry of Si-nanowire Li-ion battery anodes. Langmuir 28 965-976. doi 10.1021/la203712s... 

A sequential electrodeposition within a porous template can be used to prepare striped nanowires with tailorable dimensions and composition. Variation in composition along the length of the wire can be used to incorporate electrical functionalities, optical contrast, and the desired surface chemistry. ... 

Interestingly, hydrogermylation chemistry has been applied to Ge nanowires, providing an organic passivating layer on the nano wire [103]. Hydride-terminated Ge nanowires can be fabricated by etching Ge nanowires in HF. Unlike the surfaces of bulk Ge [13,121], H-terminated Ge nanowires are only stable for a few minutes in dry air [103]. However, the organic-terminated nano wires exhibit much better stability. 

While the discussion in this chapter has focused on molecular layers on single crystal silicon surfaces, the attachment chemistries discussed here could easily be applied to functionalize silicon nanowires or nanoparticles. Silicon nanowires have been shown to exhibit interesting electrical transport characteristics and have been used to fabricate nanoscale pn junctions [95], field effect transistors [96] and biochemical sensors [97-100]. However, all these interesting phenomena have been reported on oxidized silicon nanowires. It is likely that better control over the surface properties, as could be achieved by employing some of the chemistry discussed here, could significantly improve the performance of these nanowire-based devices. From another perspective, silicon nanowires could prove extremely... 

X. L. Liu, and C. W. Zhou, Surface treatment and doping dependence of ln2C>3 nanowires as ammonia sensors , Journal of Physical Chemistry B 107, 12451 (2003). 

Zhang Y, Kolmakov A, Libach Y, Moskovits M (2005) Electronic control of chemistry and catalysis at the surface of an individual tin oxide nanowire. J Phys Chem B 109 1923-1929... 

Figure 22 Preparation and specific recognition of surface protein imprinted polydopamine nanowires. (Reproduced from Ref. Royal Society of Chemistry, 2008.)...

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