caa a22 4500 445303891 CHVBK 20180317142606.0 cr unu---uuuuu 170323e20100201xx s 000 0 eng 10.1007/s12274-010-1010-8 doi (NATIONALLICENCE)springer-10.1007/s12274-010-1010-8 Nucleation and growth mechanisms for Pd-Pt bimetallic nanodendrites and their electrocatalytic properties [Elektronische Daten] [Byungkwon Lim, Majiong Jiang, Taekyung Yu, Pedro Camargo, Younan Xia] In a seed-mediated synthesis, nanocrystal growth is often described by assuming the absence of homogeneous nucleation in the solution. Here we provide new insights into the nucleation and growth mechanisms underlying the formation of bimetallic nanodendrites that are characterized by a dense array of Pt branches anchored to a Pd nanocrystal core. These nanostructures can be easily prepared by a one-step, seeded growth method that involves the reduction of K2PtCl4 by L-ascorbic acid in the presence of 9-nm truncated octahedral Pd seeds in an aqueous solution. Transmission electron microscopy (TEM) and high-resolution TEM analyses revealed that both homogeneous and heterogeneous nucleation of Pt occurred at the very early stages of the synthesis and the Pt branches grew through oriented attachment of small Pt particles that had been formed via homogeneous nucleation. These new findings contradict the generally accepted mechanism for seeded growth that only involves heterogeneous nucleation and simple growth via atomic addition. We have also investigated the electrocatalytic properties of the Pd-Pt nanodendrites for the oxygen reduction and formic acid oxidation reactions by conducting a comparative study with foam-like Pt nanostructures prepared in the absence of Pd seeds under otherwise identical conditions. Tsinghua University Press and Springer-Verlag Berlin Heidelberg, 2010 Palladium nationallicence platinum nationallicence seeded growth nationallicence oxygen reduction nationallicence formic acid oxidation nationallicence Lim Byungkwon Department of Biomedical Engineering, Washington University, 63130, St. Louis, Missouri, USA aut Jiang Majiong Department of Chemistry, Washington University, 63130, St. Louis, Missouri, USA aut Yu Taekyung Department of Biomedical Engineering, Washington University, 63130, St. Louis, Missouri, USA aut Camargo Pedro Department of Biomedical Engineering, Washington University, 63130, St. Louis, Missouri, USA aut Xia Younan Department of Biomedical Engineering, Washington University, 63130, St. Louis, Missouri, USA aut Nano Research Tsinghua Press 3/2(2010-02-01), 69-80 1998-0124 3:2<69 2010 3 12274 https://doi.org/10.1007/s12274-010-1010-8 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s12274-010-1010-8 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Lim Byungkwon Department of Biomedical Engineering, Washington University, 63130, St. Louis, Missouri, USA aut NATIONALLICENCE 700 1- Jiang Majiong Department of Chemistry, Washington University, 63130, St. Louis, Missouri, USA aut NATIONALLICENCE 700 1- Yu Taekyung Department of Biomedical Engineering, Washington University, 63130, St. Louis, Missouri, USA aut NATIONALLICENCE 700 1- Camargo Pedro Department of Biomedical Engineering, Washington University, 63130, St. Louis, Missouri, USA aut NATIONALLICENCE 700 1- Xia Younan Department of Biomedical Engineering, Washington University, 63130, St. Louis, Missouri, USA aut NATIONALLICENCE 773 0- Nano Research Tsinghua Press 3/2(2010-02-01), 69-80 1998-0124 3:2<69 2010 3 12274 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer