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0963-Q05-40

A Facile Solution Method to Synthesis of C60 Nanorods Bing bing Liu1, Lin Wang1, Guang tian Zou1, A. Iwasiewicz2, and Bertil Sundqvist2 1 National Lab of Superhard Materials, Jilin University, Changchun, 130012, China, People's Republic of 2 Department of Physics Umea University, Umea, Sweden

ABSTRACT We report here a facile solution method to synthesis of C60 nanorods. A very simple and effective solvent, neat m-xylene, from which C60 can rapidly grow into individual novel nanorods with widths and thicknesses of the order of nanometers was found as a shape controller. These unusual nanorods can easily grow on various substrates such as glass and silicon, and nanorods with different diameters and length-to-diameter ratios can be synthesized under different growth conditions. The smallest nanorods we obtained have widths smaller than 30 nm. The nanorods obtained are highly crystalline and single phase. INTRODUCTION One-dimensional nanometer scale materials have become the focus of intense research due to their unique structures and physical properties as well as their potential applications in the field of nanometer scale devices.1-4 Because fullerenes are among the most important novel materials in the carbon family, one-dimensional C60 has also attracted much attention in recent years. In particular, the preparation of highly crystalline C60 with a specified geometry is of great interest from both a fundamental and a practical point of view. Since the discovery of C60, quasi-one-dimensional structures such as needle-like crystals have been extensively studied.5, 6 Generally, this kind of structure can be obtained by the solution growth method, i. e., by slowly evaporating the solvent in C60 solutions. Various solvents have been investigated, such as toluene, dichloromethane, hexane, and so on.7-9 However, synthesis of well dispersed fullerene nano crystals with highly crystalline and tunable size is a challenging topic.10-13 Here, we report a facile method to synthesize fcc structural novel C60 nanorods with widths and thicknesses in the nanometer range and with rectangular cross sections, using m-xylene as shape controller. The lengths can reach tens of micrometers. The smallest C60 nanorods we obtained have widths smaller than 30 nm. A lattice expansion in the C60 nanorods was found as their widths decrease. EXPERIMENT The novel C60 nanorods were synthesized by evaporating the solution of C60 in m-xylene on silicon or glass substrates, which do not react chemically with the solvent. After evaporation the nanorods were heat treated using a tubular furnace with an accurately controlled temperature. The nanorods obtained were characterized by means of scanning electron microscopy (SEM, SSX-550 SAIMADZU, Japan), atomic force microscopy (AFM, DI Nanoscope IV, USA), Raman spectroscopy (Renishaw inVia, UK), infrared spectroscopy (IR, NICOLET AVATAR 370 DTGS), X-ray diffraction (XRD) (Rigaku D/max-RA) and transmission electron microscopy (TEM, JEM-2010, Japan). All measurements were carried out at room temp