title: Integration of Kinetic Control and Lattice Mismatch To Synthesize Pd@AuCu Core-Shell Planar Tetrapods with Size-Dependent Optical Properties.
abstract: Planar nanocrystals with multiple branches exhibit unique localized surface plasmon resonance properties and great promise in optical applications. Here, we report an aqueous synthesis of Pd@AuCu core-shell planar tetrapods through preferential overgrowth on Pd cubic seeds. The large lattice mismatch between the Pd core and the AuCu shell is the key to induce the formation of branches under sluggish reduction kinetics. Meanwhile, the capping effect of cetyltrimethylammonium chloride on the {100} facets of Pd cubes with an aspect ratio of 1.2 can determine the growth direction of AuCu branches to form a planar structure. Through simply varying the amounts of Pd cubic seeds, the sizes of products can be well-controlled in the range from 33 to 70 nm. With the manipulation of sizes, the peak position of in-plane dipole resonance can be adjusted from visible to near-infrared region. Due to the presence of tips and edges in the branches, planar tetrapods exhibited excellent surface-enhanced Raman scattering performance with an enhancement factor up to 9.0 × 10(3) for 70 nm Pd@AuCu planar tetrapods.
authors.affiliation: Hefei National Laboratory for Physical Sciences at the Microscale, Key Laboratory of Strongly-Coupled Quantum Matter Physics of Chinese Academy of Sciences, Hefei Science Center & National Synchrotron Radiation Laboratory, Department of Chemical Physics, University of Science and Technology of China , Hefei, Anhui 230026, P. R. China.
authors.forename: Min
authors.initials: M
authors.lastname: Meng
authors.affiliation: Hefei National Laboratory for Physical Sciences at the Microscale, Key Laboratory of Strongly-Coupled Quantum Matter Physics of Chinese Academy of Sciences, Hefei Science Center & National Synchrotron Radiation Laboratory, Department of Chemical Physics, University of Science and Technology of China , Hefei, Anhui 230026, P. R. China.
authors.forename: Zhicheng
authors.initials: Z
authors.lastname: Fang
authors.affiliation: Laboratory of Optical Physics, Institute of Physics, Chinese Academy of Sciences , P.O. Box 603, Beijing 100190, P. R. China.
authors.forename: Chao
authors.initials: C
authors.lastname: Zhang
authors.affiliation: Hefei National Laboratory for Physical Sciences at the Microscale, Key Laboratory of Strongly-Coupled Quantum Matter Physics of Chinese Academy of Sciences, Hefei Science Center & National Synchrotron Radiation Laboratory, Department of Chemical Physics, University of Science and Technology of China , Hefei, Anhui 230026, P. R. China.
authors.forename: Hongyang
authors.initials: H
authors.lastname: Su
authors.affiliation: Hefei National Laboratory for Physical Sciences at the Microscale, Key Laboratory of Strongly-Coupled Quantum Matter Physics of Chinese Academy of Sciences, Hefei Science Center & National Synchrotron Radiation Laboratory, Department of Chemical Physics, University of Science and Technology of China , Hefei, Anhui 230026, P. R. China.
authors.forename: Rong
authors.initials: R
authors.lastname: He
authors.affiliation: Hefei National Laboratory for Physical Sciences at the Microscale, Key Laboratory of Strongly-Coupled Quantum Matter Physics of Chinese Academy of Sciences, Hefei Science Center & National Synchrotron Radiation Laboratory, Department of Chemical Physics, University of Science and Technology of China , Hefei, Anhui 230026, P. R. China.
authors.forename: Renpeng
authors.initials: R
authors.lastname: Zhang
authors.affiliation: Hefei National Laboratory for Physical Sciences at the Microscale, Key Laboratory of Strongly-Coupled Quantum Matter Physics of Chinese Academy of Sciences, Hefei Science Center & National Synchrotron Radiation Laboratory, Department of Chemical Physics, University of Science and Technology of China , Hefei, Anhui 230026, P. R. China.
authors.forename: Hongliang
authors.initials: H
authors.lastname: Li
authors.affiliation: Laboratory of Optical Physics, Institute of Physics, Chinese Academy of Sciences , P.O. Box 603, Beijing 100190, P. R. China.
authors.forename: Zhi-Yuan
authors.initials: ZY
authors.lastname: Li
authors.affiliation: Hefei National Laboratory for Physical Sciences at the Microscale, Key Laboratory of Strongly-Coupled Quantum Matter Physics of Chinese Academy of Sciences, Hefei Science Center & National Synchrotron Radiation Laboratory, Department of Chemical Physics, University of Science and Technology of China , Hefei, Anhui 230026, P. R. China.
authors.forename: Xiaojun
authors.initials: X
authors.lastname: Wu
authors.affiliation: Hefei National Laboratory for Physical Sciences at the Microscale, Key Laboratory of Strongly-Coupled Quantum Matter Physics of Chinese Academy of Sciences, Hefei Science Center & National Synchrotron Radiation Laboratory, Department of Chemical Physics, University of Science and Technology of China , Hefei, Anhui 230026, P. R. China.
authors.forename: Chao
authors.initials: C
authors.lastname: Ma
authors.affiliation: Hefei National Laboratory for Physical Sciences at the Microscale, Key Laboratory of Strongly-Coupled Quantum Matter Physics of Chinese Academy of Sciences, Hefei Science Center & National Synchrotron Radiation Laboratory, Department of Chemical Physics, University of Science and Technology of China , Hefei, Anhui 230026, P. R. China.
authors.forename: Jie
authors.initials: J
authors.lastname: Zeng
keywords: Planar tetrapods; kinetic control; lattice mismatch; localized surface plasmon resonance; surface-enhanced Raman scattering