The Experts below are selected from a list of 8217 Experts worldwide ranked by ideXlab platform
Hiroshi Segawa - One of the best experts on this subject based on the ideXlab platform.
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pbs quantum dot based heterojunction solar cells utilizing zno nanowires for high external quantum efficiency in the near infrared region
Journal of Physical Chemistry Letters, 2013Co-Authors: Haibin Wang, Jotaro Nakazaki, Takaya Kubo, Takumi Kinoshita, Hiroshi SegawaAbstract:The improvement of solar cell performance in the near-infrared (near-IR) region is an important challenge to increase power conversion efficiency under one-Sun Illumination. PbS quantum-dot (QD)-based heterojunction solar cells with high efficiency in the near-IR region were constructed by combining ZnO nanowire arrays with PbS QDs, which give a first exciton absorption band centering at wavelengths longer than 1 μm. The morphology of ZnO nanowire arrays was systematically investigated to achieve high light-harvesting efficiency as well as efficient carrier collection. The solar cells with the PbS QD/ZnO nanowire structures made up of densely grown thin ZnO nanowires about 1.2 μm long yielded a maximum incident-photon-to-current conversion efficiency (IPCE) of 58% in the near-IR region (@1020 nm) and over 80% in the visible region (shorter than 670 nm). The power conversion efficiency obtained on the solar cell reached about 6.0% under simulated one-Sun Illumination.
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pbs quantum dot based heterojunction solar cells utilizing zno nanowires for high external quantum efficiency in the near infrared region
Journal of Physical Chemistry Letters, 2013Co-Authors: Haibin Wang, Jotaro Nakazaki, Takaya Kubo, Takumi Kinoshita, Hiroshi SegawaAbstract:The improvement of solar cell performance in the near-infrared (near-IR) region is an important challenge to increase power conversion efficiency under one-Sun Illumination. PbS quantum-dot (QD)-based heterojunction solar cells with high efficiency in the near-IR region were constructed by combining ZnO nanowire arrays with PbS QDs, which give a first exciton absorption band centering at wavelengths longer than 1 μm. The morphology of ZnO nanowire arrays was systematically investigated to achieve high light-harvesting efficiency as well as efficient carrier collection. The solar cells with the PbS QD/ZnO nanowire structures made up of densely grown thin ZnO nanowires about 1.2 μm long yielded a maximum incident-photon-to-current conversion efficiency (IPCE) of 58% in the near-IR region (@1020 nm) and over 80% in the visible region (shorter than 670 nm). The power conversion efficiency obtained on the solar cell reached about 6.0% under simulated one-Sun Illumination.
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N-fused carbazole–zinc porphyrin–free-base porphyrin triad for efficient near-IR dye-sensitized solar cells
Chemical communications (Cambridge England), 2011Co-Authors: Yizhu Liu, Hong Lin, Koichi Tamaki, Jotaro Nakazaki, Daisuke Nakayama, Satoshi Uchida, Takaya Kubo, Hiroshi SegawaAbstract:N-fused carbazole–zinc porphyrin–free-base porphyrin triad featuring an ethynyl-linkage was synthesized; efficient sensitization as long as 900 nm was demonstrated and an overall light-to-electricity conversion effciency of 5.21% was achieved under AM 1.5 G one Sun Illumination.
Thomas Cooper - One of the best experts on this subject based on the ideXlab platform.
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contactless steam generation and superheating under one Sun Illumination
Nature Communications, 2018Co-Authors: Seyed Hadi Zandavi, Yoichiro Tsurimaki, George Ni, Svetlana V. Boriskina, Thomas Cooper, Yi Huang, Gang ChenAbstract:Steam generation using solar energy provides the basis for many sustainable desalination, sanitization, and process heating technologies. Recently, interest has arisen for low-cost floating structures that absorb solar radiation and transfer energy to water via thermal conduction, driving evaporation. However, contact between water and the structure leads to fouling and pins the vapour temperature near the boiling point. Here we demonstrate solar-driven evaporation using a structure not in contact with water. The structure absorbs solar radiation and re-radiates infrared photons, which are directly absorbed by the water within a sub-100 μm penetration depth. Due to the physical separation from the water, fouling is entirely avoided. Due to the thermal separation, the structure is no longer pinned at the boiling point, and is used to superheat the generated steam. We generate steam with temperatures up to 133 °C, demonstrating superheated steam in a non-pressurized system under one Sun Illumination. Solar steam generation is limited by fouling of solar converters, and the steam temperature is usually pinned to 100 °C. Here, both limitations are overcome in a system utilizing a solar absorber and light down-converter to achieve radiative heating, which does not require physical contact between absorber and water.
Haibin Wang - One of the best experts on this subject based on the ideXlab platform.
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pbs quantum dot based heterojunction solar cells utilizing zno nanowires for high external quantum efficiency in the near infrared region
Journal of Physical Chemistry Letters, 2013Co-Authors: Haibin Wang, Jotaro Nakazaki, Takaya Kubo, Takumi Kinoshita, Hiroshi SegawaAbstract:The improvement of solar cell performance in the near-infrared (near-IR) region is an important challenge to increase power conversion efficiency under one-Sun Illumination. PbS quantum-dot (QD)-based heterojunction solar cells with high efficiency in the near-IR region were constructed by combining ZnO nanowire arrays with PbS QDs, which give a first exciton absorption band centering at wavelengths longer than 1 μm. The morphology of ZnO nanowire arrays was systematically investigated to achieve high light-harvesting efficiency as well as efficient carrier collection. The solar cells with the PbS QD/ZnO nanowire structures made up of densely grown thin ZnO nanowires about 1.2 μm long yielded a maximum incident-photon-to-current conversion efficiency (IPCE) of 58% in the near-IR region (@1020 nm) and over 80% in the visible region (shorter than 670 nm). The power conversion efficiency obtained on the solar cell reached about 6.0% under simulated one-Sun Illumination.
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pbs quantum dot based heterojunction solar cells utilizing zno nanowires for high external quantum efficiency in the near infrared region
Journal of Physical Chemistry Letters, 2013Co-Authors: Haibin Wang, Jotaro Nakazaki, Takaya Kubo, Takumi Kinoshita, Hiroshi SegawaAbstract:The improvement of solar cell performance in the near-infrared (near-IR) region is an important challenge to increase power conversion efficiency under one-Sun Illumination. PbS quantum-dot (QD)-based heterojunction solar cells with high efficiency in the near-IR region were constructed by combining ZnO nanowire arrays with PbS QDs, which give a first exciton absorption band centering at wavelengths longer than 1 μm. The morphology of ZnO nanowire arrays was systematically investigated to achieve high light-harvesting efficiency as well as efficient carrier collection. The solar cells with the PbS QD/ZnO nanowire structures made up of densely grown thin ZnO nanowires about 1.2 μm long yielded a maximum incident-photon-to-current conversion efficiency (IPCE) of 58% in the near-IR region (@1020 nm) and over 80% in the visible region (shorter than 670 nm). The power conversion efficiency obtained on the solar cell reached about 6.0% under simulated one-Sun Illumination.
Gang Chen - One of the best experts on this subject based on the ideXlab platform.
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contactless steam generation and superheating under one Sun Illumination
Nature Communications, 2018Co-Authors: Seyed Hadi Zandavi, Yoichiro Tsurimaki, George Ni, Svetlana V. Boriskina, Thomas Cooper, Yi Huang, Gang ChenAbstract:Steam generation using solar energy provides the basis for many sustainable desalination, sanitization, and process heating technologies. Recently, interest has arisen for low-cost floating structures that absorb solar radiation and transfer energy to water via thermal conduction, driving evaporation. However, contact between water and the structure leads to fouling and pins the vapour temperature near the boiling point. Here we demonstrate solar-driven evaporation using a structure not in contact with water. The structure absorbs solar radiation and re-radiates infrared photons, which are directly absorbed by the water within a sub-100 μm penetration depth. Due to the physical separation from the water, fouling is entirely avoided. Due to the thermal separation, the structure is no longer pinned at the boiling point, and is used to superheat the generated steam. We generate steam with temperatures up to 133 °C, demonstrating superheated steam in a non-pressurized system under one Sun Illumination. Solar steam generation is limited by fouling of solar converters, and the steam temperature is usually pinned to 100 °C. Here, both limitations are overcome in a system utilizing a solar absorber and light down-converter to achieve radiative heating, which does not require physical contact between absorber and water.
Peter Krogstrup - One of the best experts on this subject based on the ideXlab platform.
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Single-nanowire solar cells beyond the Shockley–Queisser limit
Nature Photonics, 2013Co-Authors: Peter Krogstrup, Henrik Ingerslev Jørgensen, Martin Heiss, Olivier Demichel, Jeppe V. Holm, Martin Aagesen, Jesper Nygard, Anna Fontcuberta I MorralAbstract:Light management is of great importance in photovoltaic cells, as it determines the fraction of incident light entering the device. An optimal p–n junction combined with optimal light absorption can lead to a solar cell efficiency above the Shockley–Queisser limit. Here, we show how this is possible by studying photocurrent generation for a single core–shell p–i–n junction GaAs nanowire solar cell grown on a silicon substrate. At 1 Sun Illumination, a short-circuit current of 180 mA cm^–2 is obtained, which is more than one order of magnitude higher than that predicted from the Lambert–Beer law. The enhanced light absorption is shown to be due to a light-concentrating property of the standing nanowire, as shown by photocurrent maps of the device. The results imply new limits for the maximum efficiency obtainable with III – V based nanowire solar cells under 1 Sun Illumination. The light concentrating properties of single p-i-n GaAs nanowires are shown to result in far greater photocurrent densities than expected under one Sun Illumination. The results suggest that such cells could in principle operate with power conversion efficiencies beyond the Shockley–Queisser limit.
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single nanowire solar cells beyond the shockley queisser limit
Nature Photonics, 2013Co-Authors: Peter Krogstrup, Henrik Ingerslev Jørgensen, Martin Heiss, Olivier Demichel, Jeppe V. Holm, Martin Aagesen, Jesper Nygard, Anna Fontcuberta I MorralAbstract:Light management is of great importance in photovoltaic cells, as it determines the fraction of incident light entering the device. An optimal p–n junction combined with optimal light absorption can lead to a solar cell efficiency above the Shockley–Queisser limit. Here, we show how this is possible by studying photocurrent generation for a single core–shell p–i–n junction GaAs nanowire solar cell grown on a silicon substrate. At 1 Sun Illumination, a short-circuit current of 180 mA cm –2 is obtained, which is more than one order of magnitude higher than that predicted from the Lambert–Beer law. The enhanced light absorption is shown to be due to a light-concentrating property of the standing nanowire, as shown by photocurrent maps of the device. The results imply new limits for the maximum efficiency obtainable with III–V based nanowire solar cells under 1 Sun Illumination.
