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Microstructure Analysis of Ni-P-rGO Electroless Composite Plating Layer for PEM Fuel Cell Separator (고분자전해질 연료전지 분리판을 위한 Ni-P-rGO 무전해 복합도금층의 미세조직 분석)

  • Kim, Yeonjae;Kim, Jungsoo;Jang, Jaeho;Park, Won-Wook;Nam, Dae-Geun
    • Journal of the Korean institute of surface engineering
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    • v.48 no.5
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    • pp.199-204
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    • 2015
  • Recently, fuel cell is a good alternative for energy source. Separator is a important component for fuel cell. In this study, The surface of separator was modified for corrosion resistance and electric conductivity. Reduced graphene oxide (rGO) was made by Staudenmaier's method. Nickel, phosphorus and rGO were coated on 6061 aluminum alloy as a separator of proton exchange membrane fuel cell by composite electroless plating. Scanning electron microscope, energy-dispersive X-ray spectroscopy and X-ray photoelectron spectroscopy were used to examine the morphology of Ni-P-rGO. Surface images were shown that the rGO was dispersed on the surface of Ni-P electroless plating, and nickel was combined with the un-reduced oxygen functional group of rGO.

Germanium Nanoparticle-Dispersed Reduced Graphene Oxide Balls Synthesized by Spray Pyrolysis for Li-Ion Battery Anode

  • Kim, Jin Koo;Park, Gi Dae;Kang, Yun Chan
    • Journal of the Korean Ceramic Society
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    • v.56 no.1
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    • pp.65-70
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    • 2019
  • Simple fabrication of a powdered Ge-reduced graphene oxide (Ge-rGO) composite via spray pyrolysis and reduction is introduced herein. Successful incorporation of the rGO nanosheets with Ge hindered the aggregation of Ge and conferred enhanced structural stability to the composite by alleviating the mechanical stress associated with drastic volume changes during repeated cycling. The Li-ion storage performance of Ge-rGO was compared with that of powdered Ge metal. The reversible discharge capacity of Ge-rGO at the $200^{th}$ cycle was $748mA\;h\;g^{-1}$ at a current density of $1.0A\;g^{-1}$ and Ge-rGO showed a capacity of $375mA\;h\;g^{-1}$ even at a high current density of $5.0A\;g^{-1}$. The excellent performance of Ge-rGO is attributed to the structural robustness, enhanced electrical conductivity, and formation of open channels between the rGO nanosheets, which facilitated electrolyte penetration for improved Li-ion diffusion.