Seed-mediated synthesis of dendritic platinum nanostructures with high catalytic activity for aqueous-phase hydrogenation of acetophenone  

作　　者：Yuan Yuan Yusuf Valentino Kaneti Minsu Liu Fangzhu Jin Danielle Frances Kennedy Xuchuan Jiang Jun Huang Aibing Yu 

机构地区：[1]School of Chemistry, University of New South Wales [2]School of Chemical and Biomolecular Engineering, The University of Sydney [3]School of Materials Science and Engineering, University of New South Wales [4]Department of Chemical Engineering, Monash University [5]Rapid Automated Materials and Processing Centre, CSIRO Manufacturing Flagship

出　　处：《Journal of Energy Chemistry》2015年第5期660-668,共9页能源化学（英文版）

基　　金：the financial support of the Australian Research Council (ARC) projects;USyd Early Career Researcher Scheme;Major Equipment Scheme;the scholarships provided by China Scholarship Council (CSC);the Commonwealth Scientific and Industrial Research Organization (CSIRO) OCE Top-up Scholarship

摘　　要：This work reports a facile and efficient seed-mediated method for the synthesis of dendritic platinum （Pt） nanoparticles （NPs） at low temperatures of 55-60 ℃ in water, using L-ascorbic acid as a reducing agent and sodium citrate as a capping agent. It is found that the dendritic Pt NPs （10-150 nm） are composed of tiny Pt nanocrystals, which nucleate and grow through the introduced smaller Pt seeds with diameters of 3-5 nm. Further investigation shows that the dendritic Pt nanostructures display excellent catalytic performance in an aqueous-phase aromatic ketone hydrogenation reaction, including： （i） acetophenone conversion rate of 〉 90%, with smaller dendritic Pt NPs （10-46 nm） offering a higher conversion efficiency; （ii） high chemoselectivity toward carbonyl group （90.6%-91.5%）, e.g., the selectivity to l-phenylethanol is -90.1% with nearly 100% acetophenone conversion for 10 nm dendritic Pt NPs within 60 rain, under mild reaction conditions （20 ℃, 1.5 bar H2 pressure, and 1.5 tool% catalyst）. The high catalytic activity, selectivity and stability of the dendritic Pt nanostructures under the organic solvent-free conditions make them promising for many potential applications in green catalytic conversion of hydrophilic biomass derived compounds.This work reports a facile and efficient seed-mediated method for the synthesis of dendritic platinum （Pt） nanoparticles （NPs） at low temperatures of 55-60 ℃ in water, using L-ascorbic acid as a reducing agent and sodium citrate as a capping agent. It is found that the dendritic Pt NPs （10-150 nm） are composed of tiny Pt nanocrystals, which nucleate and grow through the introduced smaller Pt seeds with diameters of 3-5 nm. Further investigation shows that the dendritic Pt nanostructures display excellent catalytic performance in an aqueous-phase aromatic ketone hydrogenation reaction, including： （i） acetophenone conversion rate of 〉 90%, with smaller dendritic Pt NPs （10-46 nm） offering a higher conversion efficiency; （ii） high chemoselectivity toward carbonyl group （90.6%-91.5%）, e.g., the selectivity to l-phenylethanol is -90.1% with nearly 100% acetophenone conversion for 10 nm dendritic Pt NPs within 60 rain, under mild reaction conditions （20 ℃, 1.5 bar H2 pressure, and 1.5 tool% catalyst）. The high catalytic activity, selectivity and stability of the dendritic Pt nanostructures under the organic solvent-free conditions make them promising for many potential applications in green catalytic conversion of hydrophilic biomass derived compounds.

关 键 词：Dendritic Pt nanoparticles Aqueous-phase hydrogenation Acetophenone conversionSeed mediated synthesis 

分 类 号：O643.36[理学—物理化学] TB383[理学—化学]