title: Ultrasmall Platinum Stabilized on Triphenylphosphine-Modified Silica for Chemoselective Hydrogenation.
abstract: Chemoselective hydrogenation of substrates with more than one functional group that could be hydrogenated is quite challenging and is of fundamental importance. Here, the enhanced chemoselectivity of ultrasmall (<1 nm) platinum nanoparticles (NPs) stabilized on silica modified with triphenylphosphine (PSiO2) in hydrogenation reactions is reported. Platinum NPs on PSiO2exhibit much higher selectivity than those on SiO2in the hydrogenation of acetophenone to 1-phenylethanol (99.9 versus 36 %) and hydrogenation of phenylacetylene to styrene (85 versus 52 %). The results of NMR spectroscopy, X-ray photoelectron spectroscopy, and in situ CO adsorption FTIR spectroscopy indicate the existence of strong interactions between triphenylphosphine and Pt NPs. Consequently, Pt NPs on PSiO2have smaller particle sizes and more positive Pt 4 f binding energy than those of Pt/SiO2; these are the main contributors to the superior chemoselectivity of Pt NPs. The organically modified silica could act as an efficient solid ligand for tuning the catalytic performance of metal NPs.
authors.affiliation: State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, 457-Zhongshan Road, Dalian, 116023, P.R. China.|International College, University of Chinese Academy of Sciences, Beijing, 100049, P.R. China.
authors.forename: Sanjeevi
authors.initials: S
authors.lastname: Jayakumar
authors.affiliation: State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, 457-Zhongshan Road, Dalian, 116023, P.R. China.
authors.forename: Arindam
authors.initials: A
authors.lastname: Modak
authors.affiliation: State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, 457-Zhongshan Road, Dalian, 116023, P.R. China.|University of Chinese Academy of Sciences, Beijing, 100049, P.R. China.
authors.forename: Miao
authors.initials: M
authors.lastname: Guo
authors.affiliation: State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, 457-Zhongshan Road, Dalian, 116023, P.R. China.
authors.forename: He
authors.initials: H
authors.lastname: Li
authors.affiliation: Laboratory of Fine Chemicals, Dalian Institute of Chemical Physics, P.R. China.
authors.forename: Xiangping
authors.initials: X
authors.lastname: Hu
authors.affiliation: State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, 457-Zhongshan Road, Dalian, 116023, P.R. China.
authors.forename: Qihua
authors.initials: Q
authors.lastname: Yang
keywords: P ligands; nanoparticles; platinum; polymers; supported catalysts