Carbon nanotubes were coated with a layer of nickel-cobalt-phosphorus (Ni-Co-P) alloy with different compositions of Ni/Co through electroless plating. The effects of the concentration ratio of Co^2+ to Ni^2+, bat...Carbon nanotubes were coated with a layer of nickel-cobalt-phosphorus (Ni-Co-P) alloy with different compositions of Ni/Co through electroless plating. The effects of the concentration ratio of Co^2+ to Ni^2+, bath temperature, and pH on deposition rate are discussed. The prepared carbon nanotubes covered with Ni-Co-P were characterized and analyzed by fieldemission scanning electron microscopy, transmission electron microscopy, X-ray diffraction, energy dispersive spectroscopy, and a vibrating sample magnetometer. The results show that the deposition rate reached the maximum when the concentration ratio of Co^2+ to Ni^2+ is 1 and the pH is 9; the deposition rate increases with the increase of bath temperature. The measurements of the magnetic properties of the obtained carbon nanotubes covered with Ni-Co-P indicate that the magnetic properties greatly depend on the concentration ratio of Co^2+ to Ni^2+, and the magnetic saturation reaches the maximum value when the Co^2+ to Ni^2+ ratio is 1. In addition, there are two peaks in the coercivity curve at Co^2+ to Ni^2+ ratios of 1/2 and 4/1, while the two peaks in the magnetic conductivity curve are located at Co^2+ to Ni^2+ ratios of 1/4 and 4/1.展开更多
基金ACKNOWLEDGMENTS This work was supported by Project of Fundamental Research the National Major Nanomaterials and Nanostructures (No.2005CB623603) and the National Natural Science Foundation of China (No.10674138).
文摘Carbon nanotubes were coated with a layer of nickel-cobalt-phosphorus (Ni-Co-P) alloy with different compositions of Ni/Co through electroless plating. The effects of the concentration ratio of Co^2+ to Ni^2+, bath temperature, and pH on deposition rate are discussed. The prepared carbon nanotubes covered with Ni-Co-P were characterized and analyzed by fieldemission scanning electron microscopy, transmission electron microscopy, X-ray diffraction, energy dispersive spectroscopy, and a vibrating sample magnetometer. The results show that the deposition rate reached the maximum when the concentration ratio of Co^2+ to Ni^2+ is 1 and the pH is 9; the deposition rate increases with the increase of bath temperature. The measurements of the magnetic properties of the obtained carbon nanotubes covered with Ni-Co-P indicate that the magnetic properties greatly depend on the concentration ratio of Co^2+ to Ni^2+, and the magnetic saturation reaches the maximum value when the Co^2+ to Ni^2+ ratio is 1. In addition, there are two peaks in the coercivity curve at Co^2+ to Ni^2+ ratios of 1/2 and 4/1, while the two peaks in the magnetic conductivity curve are located at Co^2+ to Ni^2+ ratios of 1/4 and 4/1.