Abstract
Thermoelectrics offer an attractive pathway for addressing an important niche in the globally growing landscape of energy demand. Nanoengineering existing low-dimensional thermoelectric materials pertaining to realizing fundamentally low thermal conductivity has emerged as an efficient route to achieve high energy conversion performance for advanced thermoelectrics. It has been proved that the figure of merit (ZT coefficient) can be enhanced by over one to two magnitudes with respect to its bulk value via nanostructuring. The significant reduced phonon thermal conductivity is found to be the main reason for this huge enhancement of ZT coefficient. In this talk, I will present how the nanostrructuring affect the transport properties of variety of materials. The central questions to be answered are: how to modulate the lattice thermal conductivity of materials by nanostructuring, what are the underlying mechanisms that leading to the change of the thermal conductivity of these nano-structures, and how to maintain (even enhance) the electrical properties of these nano-structures. Green-Kubo equilibrium molecular dynamic (GK-EMD), relaxation time approximation and iterative of the Boltzmann transport equation (BTE), and frequency/time domain direct decomposed method (F/TDDDM) which are generated by me, are used to investigate the thermal and electric properties of the nano-structures. The results of these investigations are likely to provide a major advancement to the fundamental understanding of phonon and electron behaviors of the nano-structures, with the potential to make a clear contribution to the energy efficiency of the future.

Biographical Sketch
Yanguang Zhou received the B.S. degree in Mechanical design manufacturing and automation from University of Geosciences (CUG) in 2011 and the M. E. degree in solid mechanics from Institute of Solid Mechanics, Beihang University (BUAA) in 2014. Then, he joined AICES, RWTH-Aachen university in Germany to pursue his Ph.D. His current research interests include nanoscale thermal transport in novel energy conversion, interfacial heat transfer for advanced thermal management, non-Fourier heat conduction, and thermodynamics of nanomaterials for energy nanotechnology. He has authored and co-authored more than 20 high impact journal papers.

Selected Publications
1.Y. G. Zhou, X. L. Zhang and M. Hu, Physical Review B, 92 (2015): 195204.
2.Y. G. Zhou and M. Hu, Physical Review B, 92 (2015): 195205.
3.Y. G. Zhou, X. L. Zhang and M. Hu, Nanoscale, 8 (2016): 1994-2002.
4.Y. G. Zhou and M. Hu, Nano Letters, 16 (2016): 6178.
5.Y. G. Zhou and M. Hu, Full Quantification of Three-phonon Scattering Process at Interface from Non-Equilibrium Molecular Dynamics Simulation, Physical Review B, 95 (2017): 115313.
6.Y. G. Zhou, X. J. Gong, B. Xu and M. Hu, Decouple Electronic and Phononic Transport in Nanotwinned Structure: A New Strategy for Enhancing the Figure-of-merit of Thermoelectrics, Nanoscale, 9 (2017): 9987.
7.Y. G. Zhou, X. L. Zhang and M. Hu, Nonmonotonic Diameter Dependence of Thermal Conductivity of Extremely Thin Si Nanowires: Competition between Hydrodynamic Phonon Flow and Boundary Scattering, Nano Letters, 17 (2017): 1269.