Speaker: Lorenz Kienle
Place: Yuanwanglu, 7th floor, Building Chao Kuang Piu, School of Materials Science & Engineering
Title: Complex nanostructured materials
Time: 10th Sept., 2019, 9:30 a.m.
Inviter: Xusheng Qiao
Vice Dean of the Faculty of Engineering, Kiel Univ
• Director of the Institute for Materials Science, Kiel Univ
• Head of the group “Synthesis and Real Structure“
• Head of the TEM-Center at Nanolab Kiel
• DFG Liaison Officer
Abstract:
Today’s advanced materials are coined by structural, chemical and functional properties that require combined approaches of cutting-edge methods for their characterization. In order to determine the structures on multiscales several techniques have to be combined synergistically, e.g. atomic resolution transmission electron microscopy (TEM), X-ray- and Synchrotron-based analyses. In this contribution several complex nanostructured materials will be discussed in respect to their real structure – property relationships. In case of multilayer materials the design of sensor devices is enabled via tuning of their layered components. For instance, ultra-thin films of FeCo have been magnetically decoupled by layers of TiN to ensure high thermal stability, soft magnetic behavior and a coercive field strength scaling with the individual FeCo layer thickness. Transition metal dichalcogenides are the materials of choice for achieving ultralow thermal conductivity. Moreover, these materials are of great interest for fundamental research as demonstrated by the discovery of novel transition metal based heterostructures. In case of telluride based phase change materials, the interfaces between the nanolayered components themselves are establishing the device function. Via in situ TEM the atomic processes and defect dynamics interrelated to switching can be examined, enabling the characterization of switching mechanisms. More complex nano-architectures can be produced by dedicated syntheses as demonstrated for spark plasma sintered chalcogenides and the laser ablation synthesis of bimetallic core-shell nanoparticles. In the latter case the bimetallic particles, e.g. for the system Au-Fe, can be used as templates for etching experiments thus enabling the preparation of highly porous Au nanoparticles with well-defined porosity distribution.
Publication:
[1] Direct synthesis of electrowettable carbon nanowall-diamond hybrid materials from sacrificial ceramic templates using HFCVD, Adv. Mater., 4(10), MAY 23 2017
[2] Underwater Leidenfrost nanochemistry for creation of size-tailored zinc peroxide cancer nanotherapeutics, Nature Commun., 8, MAY 12 2017
[3] Inorganic Double Helices in Semiconducting SnIP, Adv. Mater., 28(44), 9783-9791, NOV 23 2016
[4] Ultralow-fatigue shape memory alloy films, Science, 348(6238), 1004-1007, MAY 29 2015
[5] Green chemistry and nanofabrication in a levitated Leidenfrost drop, Nat. Commun., 4: 2400, OCT 2013
