A New Incorporation Method of Metallic Precursors Into a Nafion Film via a Drying Process for thePreparation of Metallic Nanocatalysts/Nafion

Abstract

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. The morphology and distribution of the Pt or Pd nanoparticles were observed by transmission electron microscopy (TEM) and elemental analysis was carried out by an energy dispersive spectroscopy (EDS), and we found that the penetration depth of the metallic nanoparticles and the particle sizes increased with increasing exposure time to the metallic precursors, and the particle size at the surface area was larger than that at the deeper area.

Preparation of Micro-sized Ni-P alloy Tube by Electroless Plating on PAN Fiber/Pd Nanoparticle Using a Drying Process

“…In our previous works, we found that ZnO and Ni-P alloy were site-selectively deposited on palladium (Pd) loaded or platinum (Pt) loaded polymer thin film [6][7][8], and we also found that palladium(II) bis(acetylacetonate), Pd(acac)2 and platinum(II) bis(acetylacetonate), Pt(acac)2 were sublimed at 180 o C in vacuum condition and the Pt(acac)2 vapors penetrated into polymer film and spontaneously reduced forming metallic (Pd and Pt) nanoparticles [9,10]. Therefore we could develop a new method to prepare micro-sized Ni-P alloy tube via using a polyacrylonitrile (PAN) fiber with μm sized diameter as a template.…”

“…Almost all Pd nanoparticles were loaded on the surface area of the PAN fiber so that the Pd nanoparticles could be acted as seeds for the growth of Ni-P alloy. Pd generation mechanism in a polymer matrix has divided into two steps [10]. That is, the mechanism was composed of (1) nucleation step and (2) growth step in a polymer matrix.…”