Synthesis, Assembly and Reactivity of Metallic Nanorods

Metal particles with dimensions on the nanometer scale are of great current interest for their unusual properties [1-3]. Fundamentally, the mean free path of an electron in a metal at room temperature is 10-100 nm, and one would predict that as the metallic particle shrinks to this dimension, unusual effects might be observed [3]. Indeed, gold nanopartides of diameter - 100 nm or less appear red (not gold) when suspended in transparent media [1-3] and gold nanopartides of diameter 3 nm are no longer noble and unreactive, but can catalyze chemical reactions [4]. 

For nanorods and nanowires, the plasmon band of the metal is split in two the 

The Chemi ry of Nanomaterials Synthesis, Properties and j plications, Volume 1. Edited by C. N. R. Rao, A. Muller, A. K. Cheetham 

Copyright 2004 WILEY-VCH Verlag GmbH Co. KGaA, Weinheim ISBN 3-527-30686-2 

All of the promise of the future technology based on nanometer-scale inorganic solids relies on the production of nanoparticles of controlled size, shape and crystal structure, and further ultimately requires that these nanoparticles be rationally linked to make a working device. Enormous progress has been made in the synthesis of inorganic nanospheres routinely, at present, control over the diameter of nanoparticles leads to particle size distributions that are within 10% of the mean diameter, and frequently within 5%. Only since the mid-1990s and later have there been good synthetic methods to make nanoparticles of controllable size and shape (other than spheres) [3, 20, 22]. 

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