title: Unusual Rh nanocrystal morphology control by hetero-epitaxially growing Rh on Au@Pt nanowires with numerous vertical twinning boundaries.
abstract: Simultaneously growing multiple nanocrystallites in a crowded space can cause a shortage of precursors, and this can lead to a vertical growth of nanocrystallites on a given substrate. The presence of surfactant-surfactant interactions among adjacent nanocrystals can also place a unique structural constraint on the growing nanocrystallites, resulting in novel nanocrystal facet control. Herein, we report the growth of Rh on Au@Pt nanowires with multiple twinning boundaries, which are found along the entire nanowire length. The Au@Pt nanowires exhibit numerous bead-like structures, resulting from the preferred Pt deposition on the twinning boundaries, which can serve as nucleation sites for Rh. The heteroepitaxial growth of Rh on the Au@Pt nanowires results in unusual crystal growth behaviours. First, novel morphologies of Rh nanorods, nanoplates, and tangled manes are obtained temperature-dependently, which are not obtained in the absence of the Au@Pt nanowire substrate. Secondly, the thickness of vertically grown nanorods and nanoplates is tightly controlled. We also report the structure-catalytic activity relationship on the catalytic hydrogenation of phthalimides by the new Rh nanostructures.
authors.affiliation: Department of Chemistry and Research Institute for Natural Sciences, Korea University, Seoul 136-701, Korea. kylee1@korea.ac.kr.
authors.forename: Hyohyun
authors.initials: H
authors.lastname: An
authors.forename: Nguyen Tien
authors.initials: NT
authors.lastname: Khi
authors.forename: Jisun
authors.initials: J
authors.lastname: Yoon
authors.forename: HyunKyung
authors.initials: H
authors.lastname: Lee
authors.forename: Hionsuck
authors.initials: H
authors.lastname: Baik
authors.forename: Jeong-Hun
authors.initials: JH
authors.lastname: Sohn
authors.forename: Kwangyeol
authors.initials: K
authors.lastname: Lee