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Jeong Young Park - One of the best experts on this subject based on the ideXlab platform.
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Hot-Electron-Mediated Surface Chemistry
Encyclopedia of Interfacial Chemistry, 2020Co-Authors: S.y. Moon, Jeong Young ParkAbstract:Hot Electrons and surface-plasmon-mediated surface chemistry have drawn much attention in the field of surface and interfacial chemistry because they are intrinsically associated with energy dissipation and conversion processes at the surface and at interfaces. In this chapter, we give an overview of the concept of Hot-Electron generation under various structural schemes, including ScHottky diodes, and the role of Hot Electrons in the catalytic activity of surface chemistry. We highlight recent studies on the relation between Hot Electrons and catalytic activity on metallic surfaces and discuss possible mechanisms for how Hot Electrons participate in chemical reactions.
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Strategies for Hot Electron-Mediated Catalytic Reactions: Catalytronics
Catalysis Letters, 2017Co-Authors: Jeong Young ParkAbstract:A pulse of high kinetic energy Electrons can be generated after deposition of external energy to a metallic surface, such as the absorption of light or exothermic chemical processes. These energetic Electrons are not at thermal equilibrium with the phonons of the metal atoms and are called “Hot Electrons”. The detection of Hot Electrons on the surface of a catalyst is an active subject in the field of surface science. More significantly, it has been found that surface processes, including desorption, diffusion, and chemical rearrangement of atomic and molecular species, are driven by the flow of Hot Electrons on the surface. The strong correlation between Hot Electron generation and surface phenomena suggests that Hot Electrons can be used to control surface chemical reactions, which is known as Hot Electron chemistry. In this Perspective, research strategies for Electronic control of catalytic reactions by engineering metal–oxide interfaces and manipulating Hot Electron flux are discussed. Catalytic nanodiodes consisting of a metal catalyst film, semiconductor layers, and Ohmic contact pads have revealed a strong correlation between the Hot Electron flux (chemicurrent) and catalytic activity under CO oxidation and hydrogen oxidation. We highlight recent results on new architecture for Hot Electron collection, including a Au/TiO_2 nanodiode and a graphene/TiO_2 nanodiode, that show that Hot Electrons can be used for quantitative measurement of catalytic activity. We show that the direct conversion of pHoton energy to Hot Electron flows can be achieved in metal–semiconductor nanodiodes. Hot Electrons and surface plasmons can be used to change the catalytic activity using metal–oxide nanocatalysts. This strategy requires an understanding of both the Electronic and chemical properties of metal–oxide interfaces, as well as the combined measurement of Electronic and chemical signals on nanoscale Electronic devices during catalytic reactions, and therefore can be referred to as “catalytronics”, which is the combination of catalysis and Electronics. Graphical Abstract
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Hot Electron and Surface Plasmon-Driven Catalytic Reaction in Metal–Semiconductor Nanostructures
Catalysis Letters, 2014Co-Authors: Jeong Young Park, Brundabana NaikAbstract: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 perspective, we outline recent research activities to develop energy conversion devices based on Hot Electrons and surface plasmons. The chemicurrent or Hot Electron flows correlate well with the turnover rate of CO oxidation or hydrogen oxidation, measured separately by gas chromatography, suggesting an intrinsic relation between the catalytic reaction and Hot Electron generation. PHoton energy can be directly converted to Hot Electron flow through the metal–semiconductor interface of Pt/TiO_2. The flow of Hot charge carriers influences the chemistry at the oxide–metal interface and the turnover rate in the chemical reaction on metal–semiconductor nanostructures. The effect of surface plasmons on the catalytic and pHotocatalytic activity on metal–oxide hybrid nanocatalysts is also highlighted. Graphical Abstract
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Hot Electron and surface plasmon driven catalytic reaction in metal semiconductor nanostructures
Catalysis Letters, 2014Co-Authors: Jeong Young Park, Brundabana NaikAbstract: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 exo- thermic 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 gener- ation 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 perspective, we outline recent research activities to develop energy conversion devices based on Hot Electrons and surface plasmons. The chemicurrent or Hot Electron flows correlate well with the turnover rate of CO oxidation or hydrogen oxidation, measured separately by gas chromatography, suggesting an intrinsic relation between the catalytic reaction and Hot Electron generation. PHoton energy can be directly converted to Hot Electron flow through the metal- semiconductor interface of Pt/TiO2. The flow of Hot charge carriers influences the chemistry at the oxide-metal inter- face and the turnover rate in the chemical reaction on metal-semiconductor nanostructures. The effect of surface plasmons on the catalytic and pHotocatalytic activity on metal-oxide hybrid nanocatalysts is also highlighted.
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surface plasmon driven Hot Electron flow probed with metal semiconductor nanodiodes
Nano Letters, 2011Co-Authors: Chan Ho Jung, Jonghyurk Park, Gabor A. Somorjai, Jeong Young ParkAbstract:A continuous flow of Hot Electrons that are not at thermal equilibrium with the surrounding metal atoms is generated by the absorption of pHotons. Here we show that Hot Electron flow generated on a gold thin film by pHoton absorption (or internal pHotoemission) is amplified by localized surface plasmon resonance. This was achieved by direct measurement of pHotocurrent on a chemically modified gold thin film of metal-semiconductor (TiO2) ScHottky diodes. The short-circuit pHotocurrent obtained with low-energy pHotons is consistent with Fowler’s law, confirming the presence of Hot Electron flows. The morphology of the metal thin film was modified to a connected gold island structure after heating such that it exhibits surface plasmon. PHotocurrent and optical measurements on the connected island structures revealed the presence of a localized surface plasmon at 550 ± 20 nm. The results indicate an intrinsic correlation between the Hot Electron flow generated by internal pHotoemission and localized surface p...
Brundabana Naik - One of the best experts on this subject based on the ideXlab platform.
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Hot Electron and Surface Plasmon-Driven Catalytic Reaction in Metal–Semiconductor Nanostructures
Catalysis Letters, 2014Co-Authors: Jeong Young Park, Brundabana NaikAbstract: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 perspective, we outline recent research activities to develop energy conversion devices based on Hot Electrons and surface plasmons. The chemicurrent or Hot Electron flows correlate well with the turnover rate of CO oxidation or hydrogen oxidation, measured separately by gas chromatography, suggesting an intrinsic relation between the catalytic reaction and Hot Electron generation. PHoton energy can be directly converted to Hot Electron flow through the metal–semiconductor interface of Pt/TiO_2. The flow of Hot charge carriers influences the chemistry at the oxide–metal interface and the turnover rate in the chemical reaction on metal–semiconductor nanostructures. The effect of surface plasmons on the catalytic and pHotocatalytic activity on metal–oxide hybrid nanocatalysts is also highlighted. Graphical Abstract
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Hot Electron and surface plasmon driven catalytic reaction in metal semiconductor nanostructures
Catalysis Letters, 2014Co-Authors: Jeong Young Park, Brundabana NaikAbstract: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 exo- thermic 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 gener- ation 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 perspective, we outline recent research activities to develop energy conversion devices based on Hot Electrons and surface plasmons. The chemicurrent or Hot Electron flows correlate well with the turnover rate of CO oxidation or hydrogen oxidation, measured separately by gas chromatography, suggesting an intrinsic relation between the catalytic reaction and Hot Electron generation. PHoton energy can be directly converted to Hot Electron flow through the metal- semiconductor interface of Pt/TiO2. The flow of Hot charge carriers influences the chemistry at the oxide-metal inter- face and the turnover rate in the chemical reaction on metal-semiconductor nanostructures. The effect of surface plasmons on the catalytic and pHotocatalytic activity on metal-oxide hybrid nanocatalysts is also highlighted.
Justin R Mulcahy - One of the best experts on this subject based on the ideXlab platform.
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surface plasmon driven Hot Electron pHotochemistry
Chemical Reviews, 2017Co-Authors: Yuchao Zhang, Shuai He, Yue Hu, Jiawei Huang, Justin R MulcahyAbstract:Visible-light-driven pHotochemistry has continued to attract heightened interest due to its capacity to efficiently harvest solar energy and its potential to solve the global energy crisis. Plasmonic nanostructures boast broadly tunable optical properties coupled with catalytically active surfaces that offer a unique opportunity for solar pHotochemistry. Resonant optical excitation of surface plasmons produces energetic Hot Electrons that can be collected to facilitate chemical reactions. This review sums up recent theoretical and experimental approaches for understanding the underlying pHotophysical processes in Hot Electron generation and discusses various Electron-transfer models on both plasmonic metal nanostructures and plasmonic metal/semiconductor heterostructures. Following that are highlights of recent examples of plasmon-driven Hot Electron pHotochemical reactions within the context of both cases. The review concludes with a discussion about the remaining challenges in the field and future oppor...
A.h. Taddiken - One of the best experts on this subject based on the ideXlab platform.
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Integration of resonant-tunneling transistors and Hot-Electron transistors
IEEE Electron Device Letters, 1994Co-Authors: T.s. Moise, A.c. Seabaugh, A.h. TaddikenAbstract:We have integrated a tunneling Hot-Electron transfer amplifier (THETA) and a novel resonant-tunneling Hot-Electron transfer amplifier (RTHETA) within a single epitaxial growth. At room temperature, the THETA exhibits a common-emitter current gain of greater than six and a voltage swing of 800 mV when measured in an inverter configuration. The RTHETA exhibits similar common-emitter current gain and a four-state voltage transfer characteristic with an output voltage swing of 1 V. In contrast to the resonant-tunneling Hot-Electron transistor (RHET), the RTHETA exhibits current gain both before and after the resonant peak voltage. From on-wafer S-parameter measurements, the current-gain cut-off frequency (f/sub T/) and the maximum frequency of oscillation f/sub max/) for both transistors are approximately 20 GHz and 9 GHz, respectively.
Yuchao Zhang - One of the best experts on this subject based on the ideXlab platform.
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surface plasmon driven Hot Electron pHotochemistry
Chemical Reviews, 2017Co-Authors: Yuchao Zhang, Shuai He, Yue Hu, Jiawei Huang, Justin R MulcahyAbstract:Visible-light-driven pHotochemistry has continued to attract heightened interest due to its capacity to efficiently harvest solar energy and its potential to solve the global energy crisis. Plasmonic nanostructures boast broadly tunable optical properties coupled with catalytically active surfaces that offer a unique opportunity for solar pHotochemistry. Resonant optical excitation of surface plasmons produces energetic Hot Electrons that can be collected to facilitate chemical reactions. This review sums up recent theoretical and experimental approaches for understanding the underlying pHotophysical processes in Hot Electron generation and discusses various Electron-transfer models on both plasmonic metal nanostructures and plasmonic metal/semiconductor heterostructures. Following that are highlights of recent examples of plasmon-driven Hot Electron pHotochemical reactions within the context of both cases. The review concludes with a discussion about the remaining challenges in the field and future oppor...