Horinouchi Shintaro, Yamanoi Yoshinori, Yonezawa Tetsu, Mouri Toshihiro, Nishihara Hiroshi
Department of Chemistry, School of Science, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan.
Langmuir. 2006 Feb 14;22(4):1880-4. doi: 10.1021/la052657+.
Monodispersed palladium nanoparticles protected with n-octyl isocyanide were prepared, and their hydrogen absorption behavior was evaluated. The formation of the nanoparticles has been confirmed by means of 1H NMR and elemental analysis. Fourier transform infrared (FT-IR) showed that three distinct bands (2156, 1964, and 1611 cm(-1)) assigned to mono-, double-, and triple-bridged isocyanide ligands on the palladium surface. The average diameter of the particles was estimated to be 2.1 +/- 0.7 nm from observation by transmission electron microscopy (TEM). X-ray photoelectron spectroscopy (XPS) analysis revealed that the particles contained Pd(0) with little amounts of Pd(II) or Pd(IV), in sharp contrast to the thiol- or phosphine-stabilized palladium nanoparticles. The absorption and desorption of hydrogen were reversible, and the reactions were much faster for the nanoparticles than for the bulk palladium metal, whereas the storage capacity was almost the same, 0.6 wt %.
制备了用正辛基异氰化物保护的单分散钯纳米颗粒,并对其吸氢行为进行了评估。通过1H NMR和元素分析证实了纳米颗粒的形成。傅里叶变换红外光谱(FT-IR)显示,在钯表面有三个分别归属于单桥、双桥和三桥异氰化物配体的不同谱带(2156、1964和1611 cm(-1))。通过透射电子显微镜(TEM)观察估计颗粒的平均直径为2.1±0.7 nm。X射线光电子能谱(XPS)分析表明,与硫醇或膦稳定的钯纳米颗粒形成鲜明对比的是,这些颗粒含有少量Pd(II)或Pd(IV)的Pd(0)。氢的吸收和解吸是可逆的,纳米颗粒的反应比块状钯金属快得多,而储存容量几乎相同,为0.6 wt%。