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Growth of Ruthenium and Ruthenium oxide nanoplates Lamartine Meda and Geoffrey D. Stevens Department of Chemistry, Xavier University of Louisiana, 1 Drexel Drive, New Orleans, LA 70125 ABSTRACT By carefully manipulating and controlling the growth conditions, Ruthenium (Ru) and ruthenium oxide (RuO2) two-dimensional (2-D) nanostructure were self-assembled into a stack of plates on indium tin oxide coated glass substrate. The nanoplates were grown in a horizontal hot-wall metalorganic chemical vapor deposition (MOCVD) from ruthenocene. Each nanoplate has a thickness in the range of 25 - 60 nm and the average area is 1000 x 300 nm2. Each stack of nanoplates is approximately 1.2 m in height. A continuous layer of Ru and RuO2 thin film, which may serve as the growth template, is observed on the bottom of the nanoplate stacks. Field-emission scanning electron microscopy reveals that each stack of nanoplates was grown vertically aligned on the substrate and exhibited elongated shape. Structural properties which were examined by X-ray diffraction show that the nanoplates are polycrystalline. INTRODUCTION Nanometer-sized materials with controlled shapes and dimensions are one of the key research areas of nanotechnology. If these materials are to be useful in electronics, biology and medical applications, full control of their structure and properties are needed through precise control of their growth processes [1-3]. Commonly used methods for the synthesis of nanometersized materials include vapor-phase transport, sol-gel, hydrothermal synthesis, electrochemical synthesis, laser ablation, and chemical vapor deposition (CVD) [1-3]. Among these methods, the vapor-liquid-synthesis (VLS) [1-4] and the vapor solid (VS) [5] growth models are the two best understood methods. In the VLS growth model, gas phase reactants dissolve in nanosized liquid droplets of a catalyst metal, followed by supersaturation and precipitation forming solid nanostructures. The VS model requires the evaporation of the desired materials which is usually performed at high temperatures and the nanostructure materials are subsequently deposited at much lower temperatures with or without a catalyst [6-9]. The metalorganic chemical vapor deposition (MOCVD) is one of the least understood methods. Here, we report on the synthesis of ruthenium (Ru) and ruthenium oxide (RuO2) twodimensional (2-D) nanomaterials grown by metalorganic chemical vapor deposition (MOCVD) method. EXPERIMENTAL DETAILS Nanoplates of Ru and RuO2 were synthesized in a horizontal hot-wall MOCVD reactor. The source precursor was ruthenocene, Ru(C5H5)2, (Strem Chemicals). An illustration of the reactor is shown in figure 1. In a typical experiment, 100 mg of ruthenocene was placed in a quartz boat which was subsequently inserted into a quartz tube. Several pieces of indium tin oxide (ITO, 15-20 nm) coated glass were cleaned and placed 5 to 10 cm from the source material. The quartz tube was then carefully inserted into the furnace and a type-R thermocouple

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was placed inside the quartz tub