【报告人】细野秀雄（Hideo Hosono）教授

【报告时间】2016年6月6日上午9:30-11:00

【报告地点】邵科馆212报告厅

【邀请人】  刘小峰 副教授，邱建荣 教授

【报告人简介】

细野秀雄（Hideo Hosono）教授现任日本东京工业大学元素战略材料研究中心主任。他是铁基超导材料的发明人，引领了超导研究领域的又一次变革。他长期致力于透明导体的研究，开发的IGZO材料已被SHARP、三星等公司用于平板显示。首次实现了让铝酸钙水泥变成了导体甚至是超导体。被誉为材料界的魔术师。

细野教授获得了诸多国际科技奖，包括今年的日本奖，麦克格雷迪新材料奖（James McGroddy Prize for New Materials，2015），以及日本学士院奖（2015）。并且由于铁基超导的发现，他在2013年获得汤姆孙－路透物理领域引文桂冠（Thomson Reuter Citation Laureate in Physics），被认为是日本最接近诺贝尔奖的科学家之一。

【报告摘要】

Electron and Hydrogen as Anions in Oxides:

Characterization and Utilization for Functional Materials

Hideo HOSONO

Materials Research Center for Element Strategy (MCES),

Tokyo Institute of Technology, Yokohama, JAPAN

 It is a grand challenge in materials science to realize valuable active functionality using abundant elements.  Electron and hydrogen are the most simple and abundant species in space.  Most of functionalities in oxides are obtained by tuning cations.  In this talk I introduce our approach to electro-active functionality in oxide-based materials focusing on electron and hydrogen as anions.

 Crystals in which electrons serve as anions are called electride, which may be regarded as the crystalline form of solvated electrons. The first electride was synthesized by J.Dye ¹⁾ in 1983 using crown-ether. The fatal drawback was extreme sensitivity to temperature and air. It was thus a long standing issue to realize RT-stable electride since then.  We reported RT stable electride C12A7:e- in 2003 using 12CaO∙7Al₂O₃(C12A7).²⁾ Since then, unique electronic structure³⁾ and physical properties have been elucidated; insulator-metal-superconductor transition⁴⁾ and very low work function (but chemical inertness) ⁵⁾ are typical examples. In addition, metallic conduction at molten state is found.⁶⁾ Recently, we reported two novel findings: Ru-loaded C12A7:e works as efficient ammonia synthesis ⁷⁾ and 2-dimensinal electride Ca₂N.⁸⁾

   Another focus is hydrogen anion H^- in oxides. We reported the incorporation of H^- ions in C12A7 in place of O²- ions and found the UV-induced insulator – electronic conductor conversion. If O^2- ion sites are replaced by H^- ion, H^- would work as an electron donor.  This approach has succeeded in heavy electron doping to iron-based superconductor LaFeAsO_1-xH_x ⁹⁾ and two Tc-dome structure ¹⁰⁾ has been found.

Ref 1) J. L. Dye et al. JACS 105, 6490(1983), 2) S. Matsuishi et al Science 301, 626(2003), 3) P. Sushko et al. PRL 91, 126401(2003), 4) H. Miyakawa et al. JACS 129,7270(2007), 5) Y. Toda et al. Adv. Mat. 19, 3564 (2007), 6) S. W. Kim et al. Science 333,71 (2011), 7) K. Lee et al. Nature 494,336(2013), 8) M. Kitano et al. Nat. Chem.  4, 934 (2012), Nat. Comm. 6, 6731, (2015). 9) S. Iimura et al. Nat.Com. 3, 943(2012), 10) M. Hiraishi et al. Nat. Phys. 10, 300 (2014).