Hot electron generation at surfaces and its impact to catalysis and renewable energy conversion
2017.04.26 13:51
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.
댓글 0
번호 | 일시 | 장소 | 연사 | 제목 |
---|---|---|---|---|
300 | Apr. 01 (Fri.) 4:15 PM | E6-2. 1st fl. #1501 | Dr. JONG SOO LIM, KIAS | Cotunneling drag effect in Coulomb-coupled quantum dots |
299 | Apr. 08 (Fri.), 13:30 PM | E6-2. 1st fl. #1501 | Dr. Yunkyu Bang, Chonnam National Univ. | Theoretical Overview of Iron-based superconductors and its future |
298 | Apr. 08 (Fri.), 4:00 PM | E6-2. 5st fl. #1501 | Dr. Changyoung Kim, SEOUL NATIONAL UNIV. | Spectroscopic studies of iron-based superconductors : what have we learned? |
297 | Apr. 09 (Mon.), 11:00 AM | E6-2. 1st fl. #1323 | Dr. Seung-Sup B. Lee |
Doublon-holon origin of the subpeaks at the Hubbard band edges
![]() |
296 | Apr. 1(Fri.), 04:00 PM | Zoom webinar | Dr. Kayoung Lee (KAIST) |
High-field Electron Transport and Interaction Induced Phenomena in 2D Materials
![]() |
295 | Apr. 12 (Tue.), 4 PM | E6-2. 1st fl. #1323 | Dr. Jeehoon Kim, POSTECH | Confinement of Superconducting Vortices in Magnetic Force Microscopy |
294 | Apr. 13(Wed.) 10:30Am | E6 #1323/zoom | Mingu Kang (Max Planck POSTECH Korea Research Initiative) | Harnessing topology and correlations from singularities in 3d-kagome metals |
293 | Apr. 19 (Fri.), 02:30 PM | E6-2. 1st fl. #1323 | Dr. YoungWoo Nam |
A family of finite-temperature electronic phase transitions in graphene multilayers
![]() |
292 | Apr. 19 (Fri.), 04:00 PM | E6-2. 1st fl. #1323 | Dr. Seok Kyun Son |
Graphene and hBN heterostructures
![]() |
291 | Apr. 19(Mon) 19:00 | Zoom webinar | Chia-Ling Chien (Johns Hopkins, USA) |
Evidence of Electrical Switching in Antiferromagnets and Coherent Spin Pumping
![]() |
290 | Apr. 19(Tue.), 2PM | #1323(E6-2. 1st fl.) | Prof. Mark Koepke, Department of Physics and Astronomy, West Virginia University, USA | Nonlocal collisional electron transport in partially ionized plasma generation, structure, and stability |
289 | Apr. 2 (Fri.), 02:30 PM | Online(Zoom) | Dr. Tae Hyun Kim (SNU) | Quantum computing and entanglement generation using trapped ions and photons |
288 | Apr. 2 (Fri.), 04:00 PM | Online(Zoom) | Dr. Heejun Yang (KAIST) | Van der Waals heterostructures for orbital gating-based phototransistors and electronic spectroscopy |
287 | Apr. 27, 2017 (Thu) 4:00 pm | Seminar Room(#1323, E6-2) | Prof.Donghan Lee (Chungnam National Univ.) | 반도체 양자점을 이용한 단광자 광원 |
» | Apr. 28 (Fri.), 02:30 PM | E6-2. 1st fl. #1323 | Dr. JeongYoung Park Graduate School of EEWS, KAIST | Hot electron generation at surfaces and its impact to catalysis and renewable energy conversion |
285 | Apr. 28 (Fri.), 04:00 PM | #1323 (E6-2. 1st fl.) | Dr. Minkyung Jung Research Institute, DGIST | Carbon nanotubes coupled to superconducting impedance matching circuits |
284 | Apr. 28 (Thu.) 3PM | #2501(E6-2. 2nd fl.) | Dr. Chang Hee Sohn, SEOUL NATIONAL UNIVERSITY | Lattice/Spin/Charge Coupling in 5d Pyrochlore Cd2Os2O7 |
283 | Apr. 5 (Tue.), 4PM | E6-2. 1st fl. #1322 | Dr. Ara Go, Columbia University | A new impurity solver for multi-orbital systems: adaptive truncation of the Hilbert space |
282 | Apr. 9 (Fri.), 10:00 AM | Zoom webinar | Prof. Marko Loncar (Harvard University, USA) |
Integrated Lithium Niobate Photonics
![]() |
281 | Apr.19 (Fri.), 11:00 AM | #1323, E6-2 | Dr. Ji-Sang Park |
First-principles studies of semiconductors for solar cell applications
![]() |