Abstract:
The present invention relates to a method for producing FRET-based dye-sensitized solar cells using water-dispersible quantum dots as donors to fluorescence resonance energy transition phenomenon (FRET), in particular, to a method for producing FRET-based dye-sensitized solar cells including water-dispersible quantum dots presenting high conversion efficiency and improved light sensitivity in a wide wavelength range of sunlight by introducing dye and FRET phenomenon between quantum dots and the dye after introducing quantum dots stabilized by citrate (citrate) ligands on the surface of the quantum dots to the titanium dioxide / FTO (Fluorine-doped Tin Oxide) electrodes. According to the present invention, the method has the advantage of expressing into the optimum environment FRET by freely adjusting the amount of water-dispersible quantum dots introduced to the emission wavelength range and the layer of nano-porous titanium dioxide. In addition, the method improves the contact between donor and acceptor by introducing water-dispersible quantum dots into the layer of nano-porous titanium dioxide to markedly enhance dispersibility. The present invention simplifies the process since the hydrophobic ligand substitution step, which was added when there was a problem in the previous approach method, is not necessary, and prevents fluorescent energy from reducing during the ligand substitution processes. [Reference numerals] (AA) Electrolyte; (BB) Quantum dot; (CC) Titanium dioxide; (DD) N719 dye
Abstract:
본 발명은 수분산성 양자점을 형광공명 에너지전이 현상(FRET)의 도너(donor)로 사용하여 FRET 기반의 염료감응 태양전지의 제조방법에 관한 것으로, 양자점 표면에 시트레이트(citrate) 리간드에 의하여 안정화된 양자점을 이산화티타늄/FTO(Fluorine-doped Tin Oxide) 전극에 도입한 후, 염료를 도입하여 양자점과 염료 상호 간의 FRET 현상에 의하여 넓은 태양광의 파장영역에서 향상된 빛 감응과 높은 전환효율을 보이는 수분산성 양자점을 포함한 FRET-기반의 태양전지의 제조방법에 관한 것이다. 본 발명에 따르면, 수분산성 양자점의 발광파장 영역대와 나노다공성 이산화티타늄 층에 도입되는 양을 자유롭게 조절하여 최적의 FRET 환경을 구현할 수 있다는 장점이 있다. 뿐만 아니라, 수분산성 양자점을 나노다공성 이산화티타늄 층 내에 도입하여 분산성을 현저히 향상시켜 도너와 억셉터간의 접촉을 향상시켰으며, 이전의 접근 방법에서 문제 시 되었던 추가적인 소수성 리간드의 치환 단계가 필요 없으므로 공정을 단순화시켰고, 리간드 치환 공정 시 발생하는 양자점의 형광 에너지의 감소현상을 방지할 수 있었다.
Abstract:
The present invention relates to a fabrication of a titanium dioxide nanoparticle in which a silver nanoparticle and a graphene quantum dot are combined and an application of the titanium dioxide nanoparticle as a photocatalyst responsive to visible light, and provides a method fabricating the nanoparticle as a titanium dioxide nanoscale composite through a reduction of a silver ion and a combination with a graphene quantum dot via a hydrothermal synthesis reaction. Also, since the present invention represents a high efficiency under visible light when used as a photocatalyst, the invention suggests applicability of the titanium dioxide nanoparticle as a next-generation photocatalyst. The present invention provides a titanium dioxide nanoscale composite into which a graphene quantum dot and a silver nanoparticle are introduced. The titanium dioxide nanoscale composite has significantly superior photocatalytic efficiency under visible light due to a high activity and a slow recombination rate under visible light region through an introduction of the graphene quantum dot with an up-conversion property and the silver nanoparticle with a strong electron storage capacity, when compared to photocatalyst particles according to a conventional art.
Abstract:
본 발명은 이산화티타늄 나노로드가 결합된 그래핀 시트의 제조와 가시광에 반응하는 광촉매로서의 응용에 관한 것으로, 비가수분해 졸-겔 반응을 통하여 산화 그래핀 층위에 이산화티타늄 나노로드를 성장시키는 방법을 제공하며, 광촉매로 이용 하였을 경우 가시광 하에서 높은 효율을 나타내므로 차세대 광촉매로의 응용 가능성을 제시하였다. 본 발명에 따르면, 올레일 아민 용액에 분산된 산화 그래핀에 이산화티타늄전구체의 도입은 비가수분해 졸-겔 반응을 유도하며, 추가적인 과정 없이 공정상 간편하게 이산화티타늄 나노로드와 그래핀 시트가 결합할 수 있는 장점을 가진다. 더욱이, 이산화티타늄 전구체의 농도를 바꿈으로써 그래핀 시트 위의 이산화티타늄 밀도를 용이하게 조절할 수 있다. 이렇게 제조된 균일한 이산화티타늄 나노로드가 결합된 그래핀 시트는 가시광선 하의 광촉매 작용에서도 상업화된 이산화티타늄 입자보다 우수한 성능을 보였다.
Abstract:
PURPOSE: A manufacturing method of a graphene sheet, which is combined with titanium dioxide nanorods, and an application as a photocatalyst response to visible light is provided to remarkably reduce problems of combining in a limited area by using a non-hydrolysis sol-gel method. CONSTITUTION: A manufacturing method of a graphene sheet, which is combined with titanium dioxide nanorods comprises the following step; a graphene oxide solution dispersed in oleoylamine is manufactured by dispersing a graphite oxide to oleylamine using an ultrasonic generator; titanium chloride which is a titanium dioxide precursor is inserted to the graphene oxide solution dispersed in oleoylamine, and produces the graphene sheet which is combined with the titanium dioxide in a nanorod form; after the graphene sheet which is combined to titanium dioxide nanorods is dried, the graphene sheet heat-treated to induce the high crystallization of the titanium dioxide and the deoxidation of the graphene oxide.
Abstract:
The present invention relates to manufacturing a graphene quantum dot, and provides a method for manufacturing the same by manufacturing a graphene oxide on which sulfate ion is coupled on the surface, and using a difference in sedimentation velocity according to the size of the graphene which results from a formation of sodium sulfate in an empty solvent. The method of the present invention provides benefits in that the graphene dot can be manufactured fast, simply, and economically through a centrifugal separation method without using a dialysis method. Moreover, the graphene quantum dot that can be manufactured in the present invention is capable of being separated and manufactured according to the size and shape of the graphene quantum dot.
Abstract:
The present invention relates to a dye-sensitized solar cell including patterned metal counter electrodes and a manufacturing method thereof. The dye-sensitized solar cell is manufactured by increasing the surface area simply by sputtering metal on a silicon wafer on which 30 nanometer patterns are formed. According to the present invention, as the surface area of a metal catalyst layer increases, electrodes for a dye-sensitized solar cell provide a sufficient surface area between the electrode and an electrolyte to activate ion exchange. As a result, the present invention can have high photoelectric conversion efficiency higher than an existing dye-sensitized solar cell. Furthermore, it is possible to easily form 30 nanometer fine metal patterns by sputtering metal on a silicon waver with patterns.