Hydrogen absorption of the polymer-coated Pd nanoparticle

Mono-dispersed palladium nanoparticles, which were coated with polymer, were prepared and their hydrogen absorption properties were investigated. The averaged diameter of the prepared particles was estimated to be 2.6 +/- 0.4 nm from a TEM photograph. By measurement of hydrogen pressure-composition isotherms, the hydrogen solubility of the I'd particles was determined to be 0.5 H per Pd. In the isotherms, plateau-like region was observed in the temperature rang of 303 to 393 K, indicating the coexistence of solid solution and hydride phases in the Pd nanoparticles in this temperature range.