1651 Pure Appl. Chem., Vol. 78, No. 9, pp. 1651–1665, 2006. doi:10.1351/pac200678091651 © 2006 IUPAC Nanorods of CoP, CdS, and ZnS* P. John Thomas, Paul Christian, Steven Daniels, Yang Li, Y. S. Wang † , and Paul O’Brien ‡ School of Chemistry, The University of Manchester, Oxford Road, Manchester, M13 9PL, UK Abstract: Simple thermolysis routes to CdS, ZnS, and CoP nanorods have been developed in our laboratory. The structural properties of the nanorods obtained were elucidated by means of X-ray diffraction (XRD) and high-resolution transmission electron microscopy (HR-TEM). Arguments and calculations in support of the contention that intrinsic rather than extrinsic factors influence the solution-phase growth of nanorods are presented. Keywords: nanorods; nanowires; crystal growth; nanomaterials; nanocrystals; particle syn- thesis. INTRODUCTION Nanowires, nanorods, and other nanodimensional material have been intensely researched in recent years because of their unique properties. At nanometric sizes, quantum confinement effects can come into play and affect most notably the electronic properties [1]. The growth of interest in this area has furthered our understanding of natural phenomena and has paved the way for building nanodevices with potential to impact our everyday life. A key step in the advance of nanoscience is devising synthetic strategies to yield nanodimensional matter with good control over shape and size. Nanorods and nanowires of metals, chalcogenides, and oxides have been obtained by different methods [2]. Many of these methods rely on templates such as porous alumina to direct the growth. There are some examples of solution-phase methods of growing nanowires or nanorods without the use of any template. CdS nanorods have been obtained by thermol- ysis of single-source precursors such as xanthates (Cd(C 2 H 5 OCS 2 ) 2 ) [3], dithiocarbamates (Cd(S 2 CNEt 2 ) 2 ) [4], and thiosemicarbazide (Cd[NH 2 CSNHNH 2 ] 2 Cl 2 ) [5] in coordinating solvents at temperatures in the range of 120–300 °C. The CdS nanorods thus produced adopt the hexagonal wurtzite form. Nanorods of magnetic Fe, Co, and Ni phosphides have been synthesized by a thermoly- sis process involving sequential or continual injection of metal-triphenylphosphine complex into a hot coordinating solvent mixture [6,7]. ZnS nanorods have been obtained in aqueous solution by the use of a liquid crystal as template [8]. Building on our experience with solution-phase synthesis of semicon- ducting nanocrystalline material, we have developed simple synthetic routes to semiconductor nanorods. In this paper, we report on the synthesis of CdS, ZnS, and CoP nanorods. The structural prop- erties of the nanorods obtained were elucidated by means of X-ray diffraction (XRD) and high-resolu- tion transmission electron microscopy (HR-TEM). We also present arguments and calculations in sup- *Paper based on a presentation at the 3 rd IUPAC Workshop on Advanced Materials (WAM III), Stellenbosch, South Africa, 5–9 September 2005. Other presentations are published in this issue, pp. 1619–1801. † Permanent address: Department of Physics, Beijing Normal University, Beijing 1000875, P.R. China ‡ Corresponding author: E-mail: paul.obrien@manchester.ac.uk