title: Palladium-pyridyl catalytic films: a highly active and recyclable catalyst for hydrogenation of styrene under mild conditions.
abstract: Palladium-pyridyl catalytic films, (PdCl2/bpy)n, were created by alternating immersions of a substrate in PdCl2 and bpy (bpy=4, 4'-bipyridyl) solutions. The as-prepared (PdCl2/bpy)10 catalyst demonstrated a remarkable catalytic activity toward hydrogenation of styrene under mild conditions and the turnover frequency (TOF) is as high as 6944h(-1). Pd(II) ions of (PdCl2/bpy)n films are in situ reduced to Pd nanoparticles (NPs) during the hydrogenation of styrene process, which results in the catalytic activity of the films. The results of X-ray photoelectron spectroscopy (XPS) and transmission electron microscopy (TEM) further demonstrate that Pd(II) ions of (PdCl2/bpy)n films were gradually converted to Pd(0) states. The catalytic activity is related to bilayer numbers and the activity increases with the number of bilayers below 10 bilayers. The solid substrates coated with (PdCl2/bpy)n multilayer catalysts were easily removed from the reaction mixture without separation filtration. Moreover, (PdCl2/bpy)n catalysts were reused for 10 consecutive reactions without loss of activity. The present (PdCl2/bpy)n heterogeneous catalysts have the advantages of easy separation and good recyclability.
authors.affiliation: State Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, The Chinese Academy of Sciences, Fuzhou 350002, China.
authors.forename: Shuiying
authors.initials: S
authors.lastname: Gao
authors.affiliation: State Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, The Chinese Academy of Sciences, Fuzhou 350002, China.
authors.forename: Weijin
authors.initials: W
authors.lastname: Li
authors.affiliation: State Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, The Chinese Academy of Sciences, Fuzhou 350002, China. Electronic address: rcao@fjirsm.ac.cn.
authors.forename: Rong
authors.initials: R
authors.lastname: Cao
keywords: Hydrogenation; Layer-by-layer self-assembly; Multilayer; Palladium; Styrene