연사: 김   성   웅  교수님 (성균관대학교 에너지과학과)

일시: 2012년 5월 23(수) 오후4:30

장소: 제1과학관 31214  e+첨단강의실

초록: 

  This talk will cover the functionalities of nanostructured oxide materials composed of ubiquitous elements, specially the electro-active functionalities of both natural and artificial nanostructured oxide. It is well-known in the college textbook that the abundant light-metal oxides such as SiO₂, Al₂O₃ and CaO are typical insulators exhibiting no electro-active functionalities. However, this common sense should be revised to that “Nanostructured light-metal oxides show the electrical conduction from semiconducting to metallic and finally to superconductivity.” This phenomenon is based on the interstitial electrons in a structural space with the size of nanoscale, which have a long history over 2 century, from the birth of solvated electrons discovered in 1806 to the recent discovery of electride materials.

Electrides, ionic compounds with electrons working as anions, are regarded as new elecro-active materials in condensed matter physics and material science. Electrides have been studied extensively owing to exotic electronic structures, relevant unique chemical and physical properties based on interstitial electrons. A discovery of new electride in light-metal oxide, 12CaO×7Al₂O₃ (C12A7) with a high stability under ambient condition, facilitates and widens the electride researches for scientific and practical applications, and changes the above-mentioned common sense in science. In this talk, a history from the birth solvated electrons discovered in 1806 to a recent achievement of our C12A7 will be introduced. Further, as a promising candidate of energy-related materials, the physical and chemical properties of electrides, being utilized as a new electron source material, will be discussed. Additionally, the artificial nanostructure between insulating oxides having a high potential as a new electronics and an energy material will be introduced.