Woodruff School of Mechanical Engineering

Seminar

Title:

Thermal Transport in Colloidal Crystals and Assemblies

Speaker:

Dr. Markus Retsch

Affiliation:

University of Bayreuth, Germany

When:

Monday, December 8, 2014 at 11:00:00 AM

Where:

MRDC Building, Room 4211

Host:

Baratunde Cola
cola@gatech.edu

Abstract

In the light of the increasing demands on efficiently using our limited energy resources, new concepts are necessary to effectively manage heat and waste heat. The long-term goal is to obtain a similar level of control over the flow of heat as it is already achieved over the flow of electrons or light.The emerging field of phononics investigates the interaction between nano- and mesostructured materials and the propagation of mechanical waves through them. Since heat is transported by phonons of very high frequencies the corresponding nanostructure also has to be realized on a few nanometer length scales. Concomitantly, the presence of interfaces and phase transitions plays a paramount role. I will present our latest results on thermal transport phenomena in colloidal materials, which are structured on length scales that bridge 10 nm up to 1 µm. I will particularly introduce two examples of so-called colloidal crystals, which comprise either monodisperse polystyrene particles or hollow silica capsules. Such systems are well suited to investigate fundamental structural changes on an individual particle level and their influence on the effective thermal conductivity of the colloidal superstructure.


Biography

Prof. Markus Retsch studied Polymer and Colloid Chemistry at the University of Bayreuth (2001 – 2006). In 2006 Prof. Retsch graduated with a diploma thesis in the group of Prof. A. H. E. Müller working on poly(acrylic acid) brushes on gold surfaces. He then moved to the Max-Planck-Institute for Polymer Research in Mainz to conduct his PhD thesis in the group of Prof. W. Knoll. There he worked on complex materials, which are accessible via colloidal self-assembly under the supervision of Prof. Jonas, with research stays at FORTH, Heraklion, Crete. In 2009, Prof. Retsch received his PhD from the Johannes Gutenberg University in Mainz. For his postdoctoral research, Prof. Retsch spent 2.5 years at the Massachusetts Institute of Technology, MIT in Cambridge, MA, USA. There he worked in the Department of Materials Science and Engineering with Prof. E. L. Thomas on optical and mechanical properties of hollow silica nanoparticles. In August 2012, Prof. Retsch was appointed Junior professor for Polymer Systems at the University of Bayreuth. In 2013 he received a Lichtenberg professorship from the Volkswagen foundation. His current research interests lie in the investigation of materials for energy conservation and conversion, accessible with colloidal assembly strategies. Throughout his career, Prof. Retsch received numerous awards and scholarships: a Bavarian scholarship throughout his studies, the Kekulé mobility stipend for his PhD, and the Feodor Lynen fellowship for his postdoctoral research.