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

• Published in: Journal of energy chemistry 2015-09, Vol.24 (5), p.660-668
• Main Authors: Yuan, Yuan, Kaneti, Yusuf Valentino, Liu, Minsu, Jin, Fangzhu, Kennedy, Danielle Frances, Jiang, Xuchuan, Huang, Jun, Yu, Aibing
• Format: Article
• Language: English
• Subjects: Acetophenone conversion; Aqueous-phase hydrogenation; Dendritic Pt nanoparticles; Seed mediated synthesis; 介导; 催化活性; 加氢反应; 树突; 水相合成; 种子; 纳米结构; 苯乙酮
• ISSN: 2095-4956
• DOI: 10.1016/j.jechem.2015.09.001

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.