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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




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
공지 2019/09/18 - 12/5  Seminar Room #1323  Prof. David Schuster and etc.  Fall 2019: Physics Seminar Serises
공지 2019/09/02 - 12/09  Seminar Room 1501  이호성 박사 (한국표준과학연구원) and etc.  Fall 2019: Physics Colloquium
274 Oct 9 (Fri), 09:00 AM  Prof. Tim Hsieh (Perimeter Institute)  Quantum Many-Body Simulation file
273 May 311 (Thu.), 04:00 PM  #1323, E6-2  Prof. Teun-Teun Kim  Dynamic control of optical properties with gated-graphene metamaterials file
272 Nov. 22th (Thur), 15:00  E6 Room(#1323)  Prof. Suprijadi Haryono  Experimental and Computational Study on Physical Properties based on Granular System file
271 Feb.17(Wed)~19(Fri), 09:00~11:00AM  Online  Prof. Subir Sachdev (Harvard University)  석학 대중 강연 및 강의 시리즈 file
270 April 4 (Thu.), 16:00 PM  #1323, E6-2  Prof. Su-Hyun Gong  Chiral spin-photon interaction at nanoscale file
269 May 24 (Fri.), 16:00 PM  #1323, E6-2  Prof. Soonjae Moon  Infrared spectroscopy study on metal-insulator transitions in layered perovskite iridates file
268 December 5 (Thu.), 16:00 PM  #1323, E6-2  Prof. Soon-Hong Kwon  Subwavelenth Photonic Devices: From Single Photon Sources to Solar Cell file
267 October 4 (Thu.), 16:00 PM  #1323, E6-2  Prof. Soo Jin Kim  Engineering light absorption in an ultrathin semiconductor metafilm file
266 July 10 (Wed.), 04:00 PM-  Academic Cltural Complex (E9) 5층 스카이라운지  Prof. Sidney Nagel/Young-Kee Kim  Public Lectures file
265 2019. 7. 16(화)  Rm. 1323 (E6-2)  Prof. Sidney Nagel  2019 Physics Distinguished Lecture file
264 December 18 (Tue.), 4:00 PM  #1323, E6-2  Prof. Shin-ichi Uchida  Road to Higher Tc Superconductivity file
263 June 14, 2016 (Tue) 3PM  #1323 (E6-2 1st fl.)  Prof. Seungyong Hahn, Florida State University  No-Insulation High Temperature Superconductor Magnet Technology for Compact, Reliable, and Low-Cost High Field DC Magnets
262 November 21 (Wed.), 15:00 PM  #1323, E6-2  Prof. Seongshik Oh  Engineering topological quantum physics at the atomic scale file
261 October 29 (Tue.), 10:00am  #1323 (E6-2, 1st fl.)  Prof. Se Kwon Kim  Unconventional Spin Transport in Quantum Materials file
260 Feb. 2(Tue) 2:30 PM  Zoom  Prof. Sangsik Kim (Texas Tech University, USA)  Quantum- & Nano-Photonics 세미나(Integrated Nanophotonics with Metamaterials, Microcomb, and Atomic Systems) file
259 NOV. 23 (Fri), 03:00 PM  E6-2. 2st fl. #2501  Prof. Sang-Jin Sin  Entanglement string and Spin Liquid with Holographic duality file
258 2018. 6. 22 10:00am ~ 11:50am  E6-6, Lecture Room 119 (1F)  Prof. Sang Bok Lee, Dept. of Chemistry and Biochemistry, Univ. of Maryland  Success in Research Career file
257 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
256 December 2(Wed), 10:00AM  Zoom  Prof. Rakshya Katiwada (Illinois Institute of Technology)  Recent progress in Axion Dark Matter eXperiment (ADMX) technology file
255 Nov 17th 12:00 PM  Online(Zoom)  Prof. Qiang Lin (Univ. of Rochester, USA)  Quantum- & Nano-Photonics" 세미나 시리즈 file