| Ni-Sn alloy powder is synthesized through a borohydride reduction with NaBH4 in a mixture of aqueous solutions of NiCl2· 6H2O, and SnCl2· 2H2O at mass ratio Ni:Sn=45:55. The ratio is chosen in accordance with the Ni-Sn binary system phase diagram. Interemtallic Ni-Sn nanoparticles are also obtained applying a template technique which involves the use of a carbon-containing support (graphite, carbon powder, carbon foam). As a result carbon - containing nanocomposites are prepared. The samples which are Ni-Sn alloys and carbon-based nanocomposites are studied by scanning electron microscopy (SEM), energy dispersitive spectroscopy (EDS), and X-ray diffraction (XRD) analysis. The influence of the different supports used on the morphology, structure, phase and surface elemental composition of the synthesized composite materials is investigated. The surface element composition has proven the existence of the Co and Sn. The ratio Ni: Sn=45:55 set in the intermetallic nanoparticles synthesis is approximately kept. Phases of Ni3Sn2, Ni3Sn4, Ni3Sn, and NiSn2 are achieved. They are in correspondence with the phase diagrams of the Ni-Sn binary systems. The obtained Ni3Sn4 phase according to literature is expected to show best properties as an electrode material. The samples are electrochemically tested by a cycling voltammetry as electrode materials in Li-ion batteries. |
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