Topic: Advancing Materials Functionalities Aided by Pressure: from Hard Materials to Electrides
Speaker: Professor Gou Huiyang
Event date: 9/26/2019
Event time: 9:30 am
Venue: Lecture Hall, 4thfloor, Building 7
Sponsor: JSNU-SPbPU Institute of Engineering, Sino-Russian Institute, School of Physics & Electronic Engineering, Institute of Science and Technology
Synthesis and characterizations of novel functional materials with unexpected properties
Employing computational tools to predict structural and physical properties of solids, which are difficult to study experimentally
Oct. 2015- Staff Scientist
Center for High Pressure Science and Technology Advanced Research (HPSTAR), Beijing, China Sept. 2013-Oct. 2015 Postdoc Associate
Geophysical Laboratory Carnegie Institution of Washington, USA Aug. 2011-Aug. 2013 Alexander von Humboldt Postdoc fellowship Bayerisches Geoinstitut, Universitaet Bayreuth, Germany
Nov. 2009-May 2011 Postdoc Associate
Department of Mechanical,Aerospace, and Nuclear Engineering, Rensselaer Polytechnic Institute Sept. 2005-Nov.2009 PH.D.
State Key Laboratory of Metastable Materials Science and Technology and College of Material Science and Engineering, Yanshan University
Sept. 2002-Jul. 2005Master.
StateKey Laboratory of Metastable Materials Science and Technology, School of Materials Science and Engineering, Yanshan University
Sept. 1996-Jul. 2000 Undergraduate student.
School of Materials Science and Engineering, Yanshan University HONORS & AWARDS (since Ph.D.)
China 1000 talents Planfor Youth, 2016
Alexander von Humboldt Postdoc fellowship, 2011-2013
Excellent Ph.D.dissertation of Hebei province, China, 2010
Excellent Ph.D.dissertation of Yanshan University, 2009
Excellent Ph.D. Student Scholarship of Yanshan University, 2008
Materials are critical for the potentially technological applications and innovations. It is now well-accepted that high pressure is an effective means to discover/modifymaterials with exciting chemical and physical properties. Here I will presentthe first high-quality HAADF-STEM imaging for boron-rich molybdenum borides by employingthe spherical aberration TEM. We obtain a highly precise local composition and atomic determinations in both Mo and boronatoms. We have successful synthesis of large-sized single-crystal molybdenumtri-boride under pressure and determined its structure, which unravels Mo atoms with partial occupancy. The functionalitesof the mechanical properties and super conductivity are also evaluated for the first time . Furthermore, we have employed synchrotron X-ray diffraction, electrical resistance measurements combined with theoretical calculations to probe the structural and electrical response of electrides (Ca2Nand Y2C) under high pressures. We found the pressure-induced metal-to-semi conductor switchingin Ca2N, together with the reductions of electronic dimensionality from 2D, 1Dto0D. For comparison, the pressure response of Y2C with the same configuration is also discussed . Our results demonstrate a feasible strategy for effective tuning the functionalities of materials under pressure.