title: Oriented-assembly of hollow FePt nanochains with tunable catalytic and magnetic properties.
abstract: Hollow nanoparticles with large surface areas exhibit a lot of advantages for applications such as catalysis and energy storage. Furthermore, their performance can be manipulated by their deliberate assemblies. Dispersive hollow FePt nanospheres have been assembled into one-dimensional hollow FePt nanochains under the magnetic fields at room temperature. Based on the activation of galvanic replacement at different reaction stages, the size of hollow FePt nanochains can be deliberately manipulated varying from 20 nm to 300 nm, together with the length changing from 200 nm to 10 μm. The competition between movement of paramagnetic Fe(3+) ions and shape recovering due to thermal fluctuations plays a critical effect on the structure of contact area between hollow nanospheres, leading to perforative structures. Compared with commercial Pt/C, well aligned hollow FePt nanochains show greatly enhanced catalytic activities in the methanol oxidation reaction (MOR) due to more favorable mass flow. Magnetic measurements indicate that the magnetic properties including Curie temperature and saturation magnetization can be tuned by the control of the size and shape of hollow nanochains.
authors.affiliation: Department of Physics, Beihang University, Beijing 100191, P. R. China and University of Science and Technology Beijing, Beijing 100083, P. R. China. sgwang@ustb.edu.cn rmwang@ustb.edu.cn.
authors.forename: Jialong
authors.initials: J
authors.lastname: Liu
authors.affiliation: Department of Physics, Beihang University, Beijing 100191, P. R. China and University of Science and Technology Beijing, Beijing 100083, P. R. China. sgwang@ustb.edu.cn rmwang@ustb.edu.cn.
authors.forename: Tianyu
authors.initials: T
authors.lastname: Xia
authors.affiliation: University of Science and Technology Beijing, Beijing 100083, P. R. China. sgwang@ustb.edu.cn rmwang@ustb.edu.cn.
authors.forename: Shouguo
authors.initials: S
authors.lastname: Wang
authors.affiliation: University of Science and Technology Beijing, Beijing 100083, P. R. China. sgwang@ustb.edu.cn rmwang@ustb.edu.cn.
authors.forename: Guang
authors.initials: G
authors.lastname: Yang
authors.affiliation: University of Science and Technology Beijing, Beijing 100083, P. R. China. sgwang@ustb.edu.cn rmwang@ustb.edu.cn.
authors.forename: Bowen
authors.initials: B
authors.lastname: Dong
authors.affiliation: State Key Laboratory of Magnetism, Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, P. R. China.
authors.forename: Chao
authors.initials: C
authors.lastname: Wang
authors.affiliation: State Key Laboratory of Magnetism, Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, P. R. China.
authors.forename: Qidi
authors.initials: Q
authors.lastname: Ma
authors.affiliation: State Key Laboratory of Magnetism, Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, P. R. China.
authors.forename: Young
authors.initials: Y
authors.lastname: Sun
authors.affiliation: University of Science and Technology Beijing, Beijing 100083, P. R. China. sgwang@ustb.edu.cn rmwang@ustb.edu.cn.
authors.forename: Rongming
authors.initials: R
authors.lastname: Wang