Modelling the formation of high aspect CdSe quantum wires: axial-growth versusoriented-attachment mechanisms

Abstract

Following the recent low temperature synthesis of high quality and single crystalCdSe quantum nanowires, we have used a thermodynamic model to investigatethe plausibility of axial-growth and oriented-attachment formation mechanisms.Using surface energies for clean and alkylamine-passivated CdSe surfaces reportedelsewhere by Manna et al (2005 J. Phys. Chem. B 109 6183), we have comparedequilibrium and metastable shapes of CdSe nanowires as a function of aspect ratioand axial orientation for different degrees of surface passivation. In general, thetheoretical results support the oriented-attachment of low aspect quantum dots ornanorods, followed by coalescence to form high aspect quantum wires.