题  目：Functions of key structural unit and performance optimization in novel thermoelectric materials

时  间：7月2日（本周五）上午9:00

地  点：小楼二楼报告厅

 

摘要：The recent progresses on enhancing conversion efficiency of thermoelectric materials will be highlighted putting the emphasis on the multi-level structure control. For CoSb3-based filled skutterudite system, after understanding the filling fraction limits for both single- and multiple- filling, we are stepping forward to maximize their TE performance through optimization of filling approach. By joining the efforts from theoretical calculations, HRTEM, inelastic neutron scattering, and property measurements, we tried to reveal some special properties due to the intrinsic cages in CoSb3 skutterudites, including the random distribution of fillers, incoherent localized rattling behavior, rattling-frequency-dependent resonant phonon scattering, and the limited but universal range of the optimum electron concentration for n-type filled CoSb3. With that, we pushed the lattice thermal conductivities of the partially filled skutterudites to their glass limit and maintained a good electrical transport, and therefore realized a very high ZT. The approach to tune TE transport by “engineering” the key structure unit have also been applied to Cu2ZnSnSe4–based compounds, which has a diamond-based structure with a key structural unit of tetrahedral blocks. The Cu2ZnSnSe4-based compounds show very low thermal conductivity primarily due to the large deformation of the tetrahedrons and randomness of multi atoms, while the perfect or undeformed compounds such as diamond and silicon always show high lattice thermal conductivities. Our work also hinted that there might exist an electron transport network, and it should not be disturbed for obtaining good electrical transport properties. By following this general understanding, we experimentally realized relatively high TE performance for a few tetrahedrally-bonded semiconductors with relatively wide gaps. Further efforts have also been made in further enhancing  performance by introducing nano structure in these novel thermoelectric materials.

 

1981年毕业于湖南大学，1984年10月赴日本留学，1990年4月在日本东北大学获工学博士学位。先后在日本株式会社RIKEN（研究员）、日本航空宇宙技术研究所（特别研究员）、美国密西根大学物理系（访问学者）、日本东北大学金属材料研究所（助手，副教授）任职和工作，2001年4月获得中国科学院百人计划

资助进入中科院上海硅酸盐研究所工作，2003年获得国家自然科学基金杰出青年科学基金。现任中国科学院上海硅酸盐研究所研究员，副所长，上海硅酸盐学会理事长。先后获得日中友好科学技术协会伏见研究奖励奖（1992年12月）、日本粉体与粉末冶金协会研究进步奖（2001年5月）、通用汽车中国科技成就一

等奖（2003年11月）、上海市优秀留学回国人才奖（2004年2月）、百人计划终期评估优秀（2004年6月）等。至今已在 Appl.Phy.Lett., Phy.Rev.Lett., J.Appl.Phys., J.Mater.Res., J.Am.Ceram.Soc.等 SCI 收录期刊上发表论文100余篇，申请专利 20 余项。