Solvothermal Synthesis And Characterization Of Nickel

This paper mainly investigate in the synthesis , characteristics and properties of NiS and NiS2.We successfully synthesize NiS of hexagonal phase in autoclave by hydrothermal method, which was reported for the first time. Also, we discussed the probable growing mechanism of the NiS nanobelts. Meantime, we prepared the NiS2 microsphere by hydro/slvo-thermal methods. And by changing the solvents or the surfactant, Ni3S4 and Ni3S2 have been prepared. The main contents are summarized as follows:1. NiS was the important member of nickel sulfide family and was investigated most widely.This material has potential application in semiconductor, optical, solar photovoltaic cells and catalysis. In this paper, we prepared NiS nanobelts with high aspect ratio. We applied Ni(CH3COO)2·4H2O and Na2S2O3·5H2O as raw materials,with no surfactant added, 200℃and synthesized NiS nanobelts of hexagonal phase. The nanobelts were 50nm in thickness,70nm-200nm in width and 10μm in length. This was reported for the first time in international to our knowledge. According to the TEM pictures, the probable process of growth and mechanism was discussed. A higer temperature was in favour of the gowth of nanobelts.2. NiS₂ was also one of the the important members of nickel sulfide family and has been investigated most widely. NiS₂ holds a triclinic phase and a cubic phase. And it is reported that cubic NiS2 possesses electronic, magnetic and optical characteristics and has potential application.In our experiment, applying Ni(CH3COO)2·4H2O and Na2S2O3·5H2O as raw materials,with EDTA added, 200℃and NiS2 microsphere of cubic phase was synthesized. When the temperature was decreased to 160℃, the obtained products were also cubic NiS2 and the morphology was the microsphere piled up tightly by cube. To investigate the probable process of growth and mechanism, a lot of contrast experiments at different time were made.3. Nickel sulfides can form various phases except for hexagonal NiS and cubic NiS₂, such as Ni3+xS2, Ni3S2, Ni7S6, Ni9S8, Ni3S4 . By changing the solvents or the surfactant, rhombohedra NiS,Ni3S4 and Ni3S2 have been prepared.