Investigation Of Transition Metal/Graphite-like Carbon Nanocomposite Composite Films By High-voltage Liquid-phase Electrochemical Deposition

In this paper, prepared GLC films and (Fe、Co、Ni)/GLC nanocomposite films by high-voltage liquid-phse electrochemical deposition. The organic solvents methanol as carbon source and the monocrystalline silicon as substrate. Research the electrochemical deposition mechanism of the nanocomposite films. We further investigated the surface morphology, microstructure, magnetic properties and field emission properties of the composite films.The main research contents of this thesis are shown as follow:(1) The Fe、Co、Ni/GLC nanocomposite films exhibited nanocomposite structure including nanocrystallites、metallic oxide and GLC matrix. XPS and Raman results showed that the sp2/sp3ratio and sp2clusters increased through doped transition metal (Fe、Co、Ni) into films. Magnetic hysteresis loop indicated that the composite films performance for soft magnetic property. The saturation magnetization and coercivity of the Co/GLC nanocomposite films was71emu/cm3and102.4Oe respectively. Metal nanocrystals doped into films improved the field emission properties of the GLC composite film. The open voltage of the Co/GLC composite films decreased from7.2V to4.4V, maximum current density increased from684uA/cm2to1469uA/cm2. Fe、Ni nanoparticles doped into the films reduced the open field. The Fe、Ni/GLC nanocomposite films showed higher current density when the electric field intensity is7.5V/m.(2) The N2can effectively inhibit the metal oxide in the process of the films deposit. The composite films exhibited nanocomposite structure including metal nanocrystallites and GLC matrix. N2make the sp2/sp3ratio of the Fe、Co、Ni/GLC composite films increased.VSM results showed that the saturation magnetization of the Fe、Co、Ni/GLC composite films was increased. This is beacause that N2can inhibiting the formation of oxide layer. In the nitrohen environment, field emission performance of the Fe、Co、Ni/GLC composite films was improved. Maximum current density of the composite films increased to193μA/cm2、2220μA/cm2and345μA/cm2.(3) Prepared the FeCo mono-doped GLC composite films. TEM analysis results showed that fullerene-like structure was in the GLC composite films. Raman spectrum analysis showed that there are two extra peaks at approximately1200and1480cm-1except classic G and D peaks. The two extra peaks come from fullerene-like structure vibration.VSM results showed that compared with the Fe/GLC and Co/GLC composite films, FeCo/GLC composite films showed higher saturation magnetization and coercivity.