周惠久论坛:邀请讲座人—颜清宇
2018-07-02 10:20:53

邀请讲座人:颜清宇

He is currently the Chair of the Electrochemical Society, Singapore Section. He is a fellow of Royal Society of Chemistry (FRSC) Since 2018. He is the board member of Materials Research Express, (an IOP Journal) since 2016. Yan has published more than 280 papers (with total ciation of >15000 and h index of 64) on two research area: (1) thermoelectric materials; (2) electrochemical properties of nanocrystals.

【报告题目】Achieving Enhanced Thermoelectric Performance in SnSe2 nanostructures

时间:  10:00-12:00 am, July 5th,2018

地点:新材料大楼材料学院第一会议

摘要】:Thermoelectric (TE) materials, which can convert heat into electricity and generate temperature gradient for cooling purpose, have been extensively studied for clean and reliable energy harvesting systems. I will discuss some of the progress in my group regarding the development of TE materials including PbTe, carbon based ones. In particular, I will discuss on a defect chemistry approach in SnSe2 nanoplate-based pellets, in which the nanoplates show preferable orientation of the (001) planes along the primary surface of the pellet (in-plane). After simultaneous introduction of Se deficiency and Cl doping, the Fermi level of SnSe2 shifts towards the conduction band, resulting in two orders of magnitude increase in carrier concentration and a transition degenerate transport behavior. In addition, all-scale hierarchical phonon scattering centers, such as point defects, nanograin boundaries, stacking faults and the layered nanostructures cooperate to produce very low lattice thermal conductivity. As a result, an enhanced in-plane ZTmax of 0.63 was achieved for 1.5 at% Cl doped SnSe1.95 pellet at 673 K, which is much higher than the corresponding in-plane ZT of pure SnSe2 (0.08).

编辑:yxh0503