Publications by authors named "Sung-Wan Hong"

Article Synopsis
  • Supercapacitors have fast charging/discharging capabilities but suffer from stability issues, which researchers aimed to improve by combining perovskite materials with graphene nanoplatelets.
  • The composite L25G70 achieved impressive performance with a capacitance retention of 95% after 5000 cycles, outperforming other composites like L75G20, which failed after 3000 cycles.
  • The study found that structural distortion induced by graphene in LSMCO enhances electrochemical performance, demonstrating that integrating these materials can significantly boost supercapacitor cycling stability.
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A new simple drying process was developed in order to prepare a metallic nanocatalysts/Nafion for self-humidifying membrane in a proton-exchange membrane fuel cell (PEMFC). Metallic precursors such as platinum(ll) bis(acetylacetonate) or palladium(ll) bis(acetylacetonate) was sublimed and simultaneously penetrated into the surface of a Nafion film. And then it was reduced to Pt or Pd nanoparticles beneath the film surface without a special reducing agent in a glass reactor of N2 atmosphere at 180 degrees C for 5, 10, 30 and 60 min, respectively.

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A simple method for the synthesis of Pt-Pd nanocatalysts was developed for a proton-exchange membrane fuel cell (PEMFC), which was loaded on a nafion coated carbon black via the sequential reduction of palladium(II) bis(acetylacetonato) and platinum(II) bis(acetylacetonato) in a drying process. Metallic precursors were sublimed and reduced on a nafion coated carbon black which was spray coated on a gas diffusion layer (GDL) in a glass reactor of N2 atmosphere at 180 degrees C for various times. The morphology and distribution of the Pt and Pd nanoparticles were observed by scanning electron microscopy (SEM) and transmission electron microscopy (TEM), and we found that the loading weight, number density and particle size of Pt-Pd nanoparticles increased with increasing exposure time at 180 degrees C.

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