• Rapid Communication in Photoscience
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• 제1권2호
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• pp.41-41
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• 2012

• Rapid Communication in Photoscience
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• 제1권2호
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• pp.48-48
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• 2012

• 한국진공학회:학술대회논문집
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• 한국진공학회 2013년도 제45회 하계 정기학술대회 초록집
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• pp.251.2-251.2
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• 2013

Natural photosynthesis utilizes two proteins, photosystem I and photosystem II, to efficiently oxidize water and reduce NADP+ to NADPH. Artificial photosynthesis which mimics this process achieve water splitting through a two-step Z-schematic water splitting process using man-made synthetic materials for hydrogen fuel production. In this study, Z-scheme system was achieved from the hybrid materials which composed of hydrogen production part as photosystem I protein and water oxidizing part as semiconductor BiVO4. Utilizing photosystem I as the hydrogen evolving part overcomes the problems of existing hydrogen evolving p-type semiconductors such as water instability, expensive cost, few available choices and poor red light (>600 nm) absorbance. Some problems of photosystem II, oxygen evolving part of natural photosynthesis, such as demanding isolation process and D1 photo-damage can also be solved by utilizing BiVO4 as the oxygen evolving part. Preceding research has not suggested any protein-inorganic-hybrid Z-scheme composed of both materials from natural photosynthesis and artificial photosynthesis. In this study, to realize this Z-schematic electron transfer, diffusion step of electron carrier, which usually degrades natural photosynthesis efficiency, was eliminated. Instead, BiVO4 and Pt-photosystem I were all linked together by the mediator gold. Synthesized all-solid-state hybrid materials show enhanced hydrogen evolution ability directly from water when illuminated with visible light.

• 조명전기설비학회논문지
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• 제25권10호
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• pp.14-22
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• 2011

The artificial lights to be introduced for the plant factories is requiring the artificial light resources with minimizing the energy consumption to reduce the greenhouse gases which is a major cause of global warming, and maximizing the efficiency in photosynthesis effect light-wave range, in which the plants can be greatly grown and developed, and having the signal light-wave range for forming the light types. the best growing and developing environment for the plants has recently realized with utilizing the LED(Lighting Emitting Diode) lamps, as a environment-friendly green lamps, which can elevating the light efficiency with using only the specific light wave range. In this study, to provide the necessary lights for the full artificial light type of the plant factory, the following research/study and experiments has been conducting. experiments of the spectrum for each light sources, and LED, The intensity of illumination, Irradiance, Photosynthesis Photon Flux Density.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2013년도 제45회 하계 정기학술대회 초록집
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• pp.280-280
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• 2013

In green plants, energy generation is accomplished through light-harvesting photosystem, which utilize abundant visible light and multi-stepwise redox reaction to oxidize water and reduce NADP+, transferring electrons efficiently with active cofactors1. Inspired by natural photosynthesis, artificial solar water-splitting devices are being designed variously. However, the several approaches involving immobilization2, conjugation3, and surface modification4 still have limitations. We have made artificial photosynthesis templates by self-assembling tyrosine-based peptide to mimick photosystem II. Porphyrin sensitizer absorbing blue light strongly was conjugated with the templates and they were hybridized with cobalt oxide through the reduction of cobalt ions in an aqueous solution. The formation of hybrid templates was characterized using TEM, and their water oxidation performance was measured by fluorescence oxygen probe. Our results suggest that the bio-templated assembly of functional compounds has a great potential for artificial photosynthesis.

• 한국산림과학회지
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• 제98권4호
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• pp.392-398
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• 2009

본 연구는 황사가 수목에 미치는 영향을 알아보기 위해 5 수종의 인위적 황사처리 이후 광합성, 호흡, 생장 및 기공에 미치는 영향을 비교하였다. 황사 처리량에 따른 생장량은 회화나무의 경우 평균 황사농도의 10배인 $5,000{\mu}g{\cdot}m^{-2}$에서 감소한 것이 관찰되었으며, 다른 수종에서는 차이가 없었다. 호흡량은 회화나무와 자작나무에서 $5,000{\mu}g{\cdot}m^{-2}$ 농도의 황사 처리에서 호흡량이 감소하였으며, 다른 수종에서는 차이가 없었다. 황사 처리량에 따른 최대광합성량은 회화나무와 자작나무에서 $500{\mu}g{\cdot}m^{-2}$ 농도의 황사 처리에서 각각 3주, 6주 이후에 감소하였고, $5,000{\mu}g{\cdot}m^{-2}$ 농도의 황사 처리에서는 처리직후 계속 감소하였다. 상수리나무, 신갈나무, 복자기는 유의성이 없었다. 광학현미경으로 회화나무의 대조구와 $5,000{\mu}g{\cdot}m^{-2}$ 농도의 황사 처리의 기공관찰 결과, $5,000{\mu}g{\cdot}m^{-2}$ 농도의 황사 처리에서 기공 내 먼지가 관찰되었다. 전자현미경으로 5수종의 잎 뒷면 기공을 관찰한 결과, 회화나무와 자작나무는 기공의 크기가 크며, 대조구와 $5,000{\mu}g{\cdot}m^{-2}$ 농도의 황사 처리에서 기공 개폐율의 차이가 컸다. 이것은 황사 먼지가 기공이 큰 수종일수록 흡입되기 쉬우며 수목의 광합성, 호흡 및 생장을 감소시킨 것으로 판단된다.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2013년도 제45회 하계 정기학술대회 초록집
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• pp.69-69
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• 2013

In the area of artificial photosynthesis, particularly for the generation of hydrogen form water, much attention has been paid on organic-inorganic hybrid system. Most of all, a dye/TiO2-combined system has been suggested and its potential utility was well manifested. However, due to its complicated nature of charge interactions in between dye and TiO2 -interface there remains a great challenge to establish the charge-activity relationship, per se light driven charge generation and recombination kinetics with respect to the amount of hydrogen produced. Further complexity of that hybrid system has been witnessed when sacrificial donor and aqueous media are considered. To unveil the operating mechanism on such a dye/TiO2-combined system, we have prepared organic dyes suitable to account for the effect of sacrificial donor as well as water interactions, and prepared the typical dye-grafted TiO2 films to investigate charge-activity relationship. Femtosecond flash photolysis clearly defined the dye effects anchored on to the TiO2 platform. In addition, photodynamic data contemplated well to the dye orientation proposed by the DFT calculations. Recent findings provide fundamental understanding on the dye-grafted TiO2 system and establish a firm background how future dye-sensitized organic-inorganic hybrid system can be designed for the light driven hydrogen generation from water.

• 한국산학기술학회논문지
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• 제19권1호
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• pp.63-68
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• 2018

본 논문은 이산화탄소 고정 과정이 포함된 인공 광합성 과정을 모사하기 위하여 지구상에 흔히 존재하는 촉매 재료를 이용해 개발한 광화학 반응 시스템(인공나뭇잎)과 시스템 에너지 포집 및 변환 능력에 대한 성능을 조사하기 위한 기초 연구 결과를 제시한다. 본 연구에서 개발한 시스템은 태양광 전지의 전면부에 산화코발트를 도핑 하여 물의 전기분해로 인한 산소 발생이 태양전지 표면에서 직접 발생하도록 하였고, 후면 기판 표면에는 이산화탄소 변환 반응을 위한 효율적인 촉매로 $MoS_2$를 도핑 하여, 전선이 없는 구조로 구성하였다. 직접 태양광 연료 변환 시스템은 약4.5%로 이산화탄소를 일산화탄소와 수소로 변환하여 지속 가능한 연료(합성가스)의 형태로 생산하며, 이는 음극에서 촉매 변환 효율이 75%이상이 될 수 있음을 의미한다. 본 연구는 물의 광분해뿐만 아니라 태양광에 의해 유도된 이산화탄소 전환 과정을 하나의 시스템에서 동시에 실현하여 자연적 광합성 과정을 좀 더 성공적으로 모사할 수 있는 시스템 개발에 기여하였다.

• 정보과학회지
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• 제28권7호
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• pp.52-58
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• 2010

• 한국광과학회:학술대회논문집
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• 한국광과학회 1999년도 학술대회지
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• pp.13-14
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• 1999