visual
visual

세미나

  • HOME
  • >
  • 소식
  • >
  • 세미나
장소 E6-2. 1st fl. #1323 
일시 Apr. 28 (Fri.), 02:30 PM 
연사 Dr. JeongYoung Park Graduate School of EEWS, KAIST 

 

Hot electron generation at surfaces and its impact to catalysis and renewable energy conversion

 

Dr. JeongYoung Park

Graduate School of EEWS, KAIST

Apr. 28 (Fri.), 02:30 PM

E6-2. 1st fl. #1323

 

 

Abstract: 

A pulse of high kinetic energy electrons (1–3 eV) in metals can be generated after surface exposure to external energy, such as the absorption of light or exothermic chemical processes. These energetic electrons are not at thermal equilibrium with the metal atoms and are called ‘‘hot electrons’’. The detection of hot electrons and understanding the correlation between hot electron generation and surface phenomena are challenging questions in the surface science and catalysis community. Hot electron flow generated on a gold thin film by photon absorption (or internal photoemission) appears to be correlated with localized surface plasmon resonance. 

In this talk, I will show strategy to quantify the non-adiabatic energy transfer and detect hot electron flux during the elementary steps of the energy conversion process and catalytic reaction processes occurring at both of solid-gas and solid-liquid interfaces. To detect and utilize the hot electron flows, the nanodiodes consisting of metal catalyst film, semiconductor layers, and Ohmic contact pads were constructed It was shown that the chemicurrent or hot electron flows were well correlated with the turnover rate of CO oxidation or hydrogen oxidation separately measured by gas chromatography, suggesting the intrinsic relation between catalytic reaction and hot electron generation. We show a novel scheme of graphene catalytic nanodiode composed of a Pt NPs array on graphene/TiO2 Schottky nanodiode, which allows detection of hot electron flows induced by hydrogen oxidation on Pt NPs. By analyzing the correlation between the turnover rate (catalytic activity) and hot electron current (chemicurrent) measured on the graphene catalytic nanodiodes, we demonstrate that the catalytic nanodiodes utilizing a single graphene layer for electrical connection of Pt NPs are beneficial for the detection of hot electrons due to not only atomically thin nature of graphene but also reducing the height of the potential barrier existing at the Pt NPs/graphene interface. I will show that hot electron flow generated on a gold thin film by photon absorption (or internal photoemission) is amplified by localized surface plasmon resonance. Finally, The effect of surface plasmons on the catalytic and photocatalytic activity on metal–oxide hybrid nanocatalysts is also highlighted. These phenomena imply the efficient energy conversion from the photon energy to the chemical energy, with the potential application of hot electron-based photocatalytic devices.

 

 

 

번호 일시 장소 연사 제목
312 4. 11(월),16:00  E6, #1501  노재동교수 (서울시립대 물리학과)  Emergence of Statistical Mechanics in Quantum Systems
311 4. 25(월), 16:00  E6, #1501  정영욱 책임연구원 (한국원자력연구원)  Ultrafast electron beam, a tool to explore the nanoscopic world of materials(우리말강의)
310 4. 4(월), 16:00  E6, #1501  김희철교수 (Postech 물리학과)  New paradigms in Quantum Field Theory
309 4pm, 10th May  E6 1323  권혁준 (Korea Institute for Advanced Study, KIAS)  (광학분야 특별세미나)Testing quantum thermodynamics using quantum optics
308 4pm, 14th April  E6 1323  신승우 (KAIST 물리학과)  (광학분야 특별세미나)Holographic tomography of dielectric tensors at optical frequency
307 4pm, 26th May  E6 1323  황민수 (Department of Physics, Korea University)  (광학분야 특별세미나)Topological photonic devices
306 4pm, 28th April  E6 1323  유경식 (KAIST 전기및전자공학부)  (광학분야 특별세미나)Adiabaticity and symmetry in optical waveguide design
305 4pm, 31th March  online  최현용 (서울대학교 물리천문학부)  (광학분야 특별세미나)Ultrafast time-resolved spectroscopy in topological materials
304 4pm, Sep. 21 (Wed.  E6-2. #2502(2nd fl.)  Dr. Henrik Johannesson , University of Gothenburg (Sweden) and Beijing Computational Science Research Center (China)  Entanglement probe of two-impurity Kondo physics
303 4월 18일(월), 15:30~  KI빌딩(E4), 강의실 B501 (5F)  Prof. Robert A. DiStasio Jr. (Cornell University)  First Principles Approaches for Intermolecular Interactions: From Gas-Phase Dimers to Liquid Water and Molecular Crystal Polymorphism file
302 5. 2(월),16:00  E6, #1501  유상운교수 (한밭대)  What can we learn from the history of science and technology?(우리말강의)
301 5. 23(월),16:00  E6, #1501  김준성교수 (postech 물리학과)  Novel electronic transport in topological van der Waals magnets
300 5. 30(월), 16:00  E6, #1501  공수현교수 (고려대학교 물리학과)  Light manipulation using 2D layered semiconductors
299 5. 9(월),16:00  E6, #1501  김창영교수 (서울대)  Searching for new electronic properties in correlated material flatland
298 5.16(월),16:00  E6, #1501  조규붕교수 (HKUST)  Design synthetic topological matter with atoms and lights
297 5월 17일(화), 11:00 ~ 12:00  창의학습관(E11), 406호  방준혁 박사(Korea Basic Science Institute, KBSI)  The CERN Resonant WISP Search: Development, Results and Lesson-Learned
296 5월27일(목) 오후4시  온라인  박소현 박사(CERN) / 이혜성 교수(KAIST)  찾아가는 물리연구 현장(유럽 입자물리학연구소 소개) file
295 7월 29일(목) 오후 2시 ~ 오후 4시  Online seminar  Dr. Kunio Kaneta(KIAS)  Gravitationally Induced Dark Sector and Inflationary Dynamics file
294 8/19 (Mon), 10:00~11:30, 8/22 (Thur), 10:00~11:30  Rm. 1322, E6-2  Nicolas Treps  Tutorials on Multimode Quantum Optics in the Continuous Variable Regime file
293 Apr. 01 (Fri.) 2:30 PM  E6-2. 1st fl. #1501  Dr. KICHEON KANG, Chonnam National University  Interference of single charged particles without a loop and dynamic nonlocality