The Experts below are selected from a list of 360 Experts worldwide ranked by ideXlab platform
Jinsang Kim - One of the best experts on this subject based on the ideXlab platform.
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molecular Design Principle of all organic dyes for dye sensitized solar cells
ChemInform, 2013Co-Authors: Bonggi Kim, Kyeongwoon Chung, Jinsang KimAbstract:All-organic dyes have shown promising potential as an effective sensitizer in dye-sensitized solar cells (DSSCs). The Design concept of all-organic dyes to improve light-to-electric-energy conversion is discussed based on the absorption, electron injection, dye regeneration, and recombination. How the electron-donor-acceptor-type framework can provide better light harvesting through bandgap-tuning and why proper arrangement of acceptor/anchoring groups within a conjugated dye frame is important in suppressing improper charge recombination in DSSCs are discussed. Separating the electron acceptor from the anchoring unit in the donor-acceptor-type organic dye would be a promising strategy to reduce recombination and improve photocurrent generation.
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a molecular Design Principle of lyotropic liquid crystalline conjugated polymers with directed alignment capability for plastic electronics
Nature Materials, 2013Co-Authors: Bonggi Kim, Eun Jeong Jeong, Jongsoo Won Chung, Sungbaek Seo, Bonwon Koo, Jinsang KimAbstract:Conjugated polymers with a one-dimensional p-orbital overlap exhibit optoelectronic anisotropy. Their unique anisotropic properties can be fully realized in device applications only when the conjugated chains are aligned. Here, we report a molecular Design Principle of conjugated polymers to achieve concentration-regulated chain planarization, self-assembly, liquid-crystal-like good mobility and non-interdigitated side chains. As a consequence of these intra- and intermolecular attributes, chain alignment along an applied flow field occurs. This liquid-crystalline conjugated polymer was realized by incorporating intramolecular sulphur-fluorine interactions and bulky side chains linked to a tetrahedral carbon having a large form factor. By optimizing the polymer concentration and the flow field, we could achieve a high dichroic ratio of 16.67 in emission from conducting conjugated polymer films. Two-dimensional grazing-incidence X-ray diffraction was performed to analyse a well-defined conjugated polymer alignment. Thin-film transistors built on highly aligned conjugated polymer films showed more than three orders of magnitude faster carrier mobility along the conjugated polymer alignment direction than the perpendicular direction.
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Design Principle of conjugated polyelectrolytes to make them water soluble and highly emissive
Advanced Functional Materials, 2012Co-Authors: Kangwon Lee, Hyongjun Kim, Jinsang KimAbstract:The correlation between the molecular Design of a conjugated polyelectrolyte (CPE) and its aggregated structure and the emissive properties in water is systematically investigated by means of UV–vis spectrometry, fluorescence spectroscopy, and scanning/transmission electron microscopy. Five different and rationally Designed CPEs having carboxylic acid side chains are synthesized. All five conjugated polyelectrolytes are seemingly completely soluble in water in visual observation. However, their quantum yields are dramatically different, changing from 0.45 to 51.4%. Morphological analysis by electron microscopy combined with fluorescence spectrophotometry reveals that the CPEs form self-assembled aggregates at the nanoscale depending on the nature of their side chains. The feature of the self-assembled aggregates directly determines the emissive property of the CPEs. The nature and the length of the spacer between the carboxylic acid group and the CPE backbone have a strong influence on the quantum yield of the CPEs. Our study demonstrates that bulky and hydrophilic side chains and spacers are required to achieve complete water-solubility and high quantum yield of CPEs in water, providing an important molecular Design Principle to develop functional CPEs.
Donghyo Hahm - One of the best experts on this subject based on the ideXlab platform.
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Design Principle for bright robust and color pure inp znsexs1 x zns heterostructures
Chemistry of Materials, 2019Co-Authors: Donghyo Hahm, Jun Hyuk Chang, Byeong Guk Jeong, Philip Park, Jongha Choi, Seunghyun Rhee, Kookheon CharAbstract:Advance in wet chemistry enables the sophisticated Design of nanocrystal quantum dots (QDs) and allows unprecedented color purity and brightness, promising their useful applications in a variety of light-emitting applications. A representative example is core/shell heterostructures, in which charge carriers are effectively decoupled from structural artifacts to generate photons efficiently. Despite the development of widely accepted synthetic protocols for Cd- or Pb-based QDs, the progress in heterostructuring environmentally benign QDs has been lagging behind, and so is the practical use of these QDs. Herein, we present a Design Principle for InP/ZnSexS1–x heterostructured QDs. A principal Design approach is the growth of uniformly thick inorganic shell consisting of a ZnSexS1–x inner shell and a ZnS outermost shell that effectively confines electrons from spreading inward of QDs. Comprehensive studies across synthesis, spectroscopic analysis, and calculation uncover that the presence of Se near the InP ...
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Design Principle for bright robust and color pure inp znsexs1 x zns heterostructures
Chemistry of Materials, 2019Co-Authors: Donghyo Hahm, Jun Hyuk Chang, Byeong Guk Jeong, Philip Park, Jongha Choi, Seunghyun Rhee, Jaeyoul Kim, Seongjae Lee, Whi Dong Kim, Jaehoon LimAbstract:Advance in wet chemistry enables the sophisticated Design of nanocrystal quantum dots (QDs) and allows unprecedented color purity and brightness, promising their useful applications in a variety of...
Kookheon Char - One of the best experts on this subject based on the ideXlab platform.
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Design Principle for bright robust and color pure inp znsexs1 x zns heterostructures
Chemistry of Materials, 2019Co-Authors: Donghyo Hahm, Jun Hyuk Chang, Byeong Guk Jeong, Philip Park, Jongha Choi, Seunghyun Rhee, Kookheon CharAbstract:Advance in wet chemistry enables the sophisticated Design of nanocrystal quantum dots (QDs) and allows unprecedented color purity and brightness, promising their useful applications in a variety of light-emitting applications. A representative example is core/shell heterostructures, in which charge carriers are effectively decoupled from structural artifacts to generate photons efficiently. Despite the development of widely accepted synthetic protocols for Cd- or Pb-based QDs, the progress in heterostructuring environmentally benign QDs has been lagging behind, and so is the practical use of these QDs. Herein, we present a Design Principle for InP/ZnSexS1–x heterostructured QDs. A principal Design approach is the growth of uniformly thick inorganic shell consisting of a ZnSexS1–x inner shell and a ZnS outermost shell that effectively confines electrons from spreading inward of QDs. Comprehensive studies across synthesis, spectroscopic analysis, and calculation uncover that the presence of Se near the InP ...
Seunghyun Rhee - One of the best experts on this subject based on the ideXlab platform.
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Design Principle for bright robust and color pure inp znsexs1 x zns heterostructures
Chemistry of Materials, 2019Co-Authors: Donghyo Hahm, Jun Hyuk Chang, Byeong Guk Jeong, Philip Park, Jongha Choi, Seunghyun Rhee, Kookheon CharAbstract:Advance in wet chemistry enables the sophisticated Design of nanocrystal quantum dots (QDs) and allows unprecedented color purity and brightness, promising their useful applications in a variety of light-emitting applications. A representative example is core/shell heterostructures, in which charge carriers are effectively decoupled from structural artifacts to generate photons efficiently. Despite the development of widely accepted synthetic protocols for Cd- or Pb-based QDs, the progress in heterostructuring environmentally benign QDs has been lagging behind, and so is the practical use of these QDs. Herein, we present a Design Principle for InP/ZnSexS1–x heterostructured QDs. A principal Design approach is the growth of uniformly thick inorganic shell consisting of a ZnSexS1–x inner shell and a ZnS outermost shell that effectively confines electrons from spreading inward of QDs. Comprehensive studies across synthesis, spectroscopic analysis, and calculation uncover that the presence of Se near the InP ...
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Design Principle for bright robust and color pure inp znsexs1 x zns heterostructures
Chemistry of Materials, 2019Co-Authors: Donghyo Hahm, Jun Hyuk Chang, Byeong Guk Jeong, Philip Park, Jongha Choi, Seunghyun Rhee, Jaeyoul Kim, Seongjae Lee, Whi Dong Kim, Jaehoon LimAbstract:Advance in wet chemistry enables the sophisticated Design of nanocrystal quantum dots (QDs) and allows unprecedented color purity and brightness, promising their useful applications in a variety of...
Byeong Guk Jeong - One of the best experts on this subject based on the ideXlab platform.
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Design Principle for bright robust and color pure inp znsexs1 x zns heterostructures
Chemistry of Materials, 2019Co-Authors: Donghyo Hahm, Jun Hyuk Chang, Byeong Guk Jeong, Philip Park, Jongha Choi, Seunghyun Rhee, Kookheon CharAbstract:Advance in wet chemistry enables the sophisticated Design of nanocrystal quantum dots (QDs) and allows unprecedented color purity and brightness, promising their useful applications in a variety of light-emitting applications. A representative example is core/shell heterostructures, in which charge carriers are effectively decoupled from structural artifacts to generate photons efficiently. Despite the development of widely accepted synthetic protocols for Cd- or Pb-based QDs, the progress in heterostructuring environmentally benign QDs has been lagging behind, and so is the practical use of these QDs. Herein, we present a Design Principle for InP/ZnSexS1–x heterostructured QDs. A principal Design approach is the growth of uniformly thick inorganic shell consisting of a ZnSexS1–x inner shell and a ZnS outermost shell that effectively confines electrons from spreading inward of QDs. Comprehensive studies across synthesis, spectroscopic analysis, and calculation uncover that the presence of Se near the InP ...
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Design Principle for bright robust and color pure inp znsexs1 x zns heterostructures
Chemistry of Materials, 2019Co-Authors: Donghyo Hahm, Jun Hyuk Chang, Byeong Guk Jeong, Philip Park, Jongha Choi, Seunghyun Rhee, Jaeyoul Kim, Seongjae Lee, Whi Dong Kim, Jaehoon LimAbstract:Advance in wet chemistry enables the sophisticated Design of nanocrystal quantum dots (QDs) and allows unprecedented color purity and brightness, promising their useful applications in a variety of...
