Ti 보호층이 형성된 스테인레스 스틸 메쉬 전극을 이용한 염료감응형 태양전지의 전기 화학적 특성 개선

정행윤,기현철,구할본,Jung, Haeng-Yun,Ki, Hyun-Chul,Gu, Hal-Bon 한국전기전자재료학회 2015 전기전자재료학회논문지 Vol.28 No.3

Stainless steel (SS) mesh was used to fabricate photoelectrode for flexible dye-seisitzed solar cells (DSSCs) in order to evaluate them as replacements for more expensive transparent conductive oxide(TCO). We fabricated the DSSCs with new type of photoelectrode, which consisted of flexible SS mesh coated with 100 nm thickness titanium (Ti) protective layer deposited using electron-beam deposition system. SS mesh DSSCs with protective layer showed higher efficiency than those without a protective layer. The best cell property in the present study showed the open circuit voltage (Voc) of 0.608 V, short-circuit current density (Jsc) of $5.73mA\;cm^{-2}$, fill factor (FF) of 65.13%, and efficiency (${\eta}$) of 2.44%. Compared with SS mesh based on DSSCs (1.66%), solar conversion of SS mesh based on DSSCs with protective layer improved about 47%.

염료감응형 태양전지의 광전변환효율 향상을 위한 무반사 박막

정행윤,기현철,홍경진,Jung, Haeng-Yun,Ki, Hyun-Chul,Hong, Kyung-Jin 한국전기전자재료학회 2016 전기전자재료학회논문지 Vol.29 No.12

DSSCs (dye-sensitized solar cells) based on $TiO_2/SiO_2$ multi layer AR (anti-reflection) coating on the outer glass FTO (fluorine-doped tin oxide) substrate are investigated. We have coated an AR layer on the surface of a DSSCs device by using an IAD (ion beam-assisted deposition) system and investigated the effects of the AR layer by measuring photovoltaic performance. Compared to the pure FTO substrate, the multi layer AR coating increased the total transmittance from 67.4 to 72.9% at 530 nm of wavelength. The main enhancement of solar conversion efficiency is attributed to the reduction of light reflection at the FTO substrate surface. This leads to the increase of Jsc and the efficiency improvement of DSSCs.

Ti 전극의 Lift-off 공정을 이용한 홀 패턴 형성과 TCO-less 염료감응형 태양전지의 응용

정행윤,기현철,구할본,Jung, Haeng-Yun,Ki, Hyun-Chul,Gu, Hal-Bon 한국전기전자재료학회 2015 전기전자재료학회논문지 Vol.28 No.3

In this study, we propose Ti hole pattern structure on the transparent conductive oxide (TCO) less dye-sensitized solar cells (DSSCs) using the lift-off process to improve the low light transmittance and low efficiency caused by opaque Ti electrode. The formation of Ti hole patterns make it possible to move the dye adsorption and electrolyte. The DSSCs with Ti hole patterns showed a higher photoelectric conversion efficiency (PCE) than those with general structure by 11.1%. As a result, The Ti hole pattern structure can be improved to increase the light absorption of the dyes and PCE of the TCO-less DSSCs is also increased.

저가의 Ti 박막이 증착된 유리 기판을 사용한 TCO-less 염료감응형 태양전지의 응용

정행윤,기현철,구할본,Jung, Haeng-Yun,Ki, Hyun-Chul,Gu, Hal-Bon 한국전기전자재료학회 2014 전기전자재료학회논문지 Vol.27 No.11

In this study, a transparent conductive oxide (TCO)-less dye-sensitized solar cells (DSSCs) was fabricated by using titanium (Ti) electrode to replace the Fluorine-doped tin oxide (FTO) for the reduction of manufacturing cost. Ti film was formed by electron beam evaporation method and the results showed the sheet resistance of Ti electrodes with a thikness of 500 nm similar to FTO. In case of power conversion efficiency (PCE), a DSSC with Ti electrodes showed a lower value than that with FTO by 0.38%. For the investigation of the difference, the DSSCs were measured and analyzed by using electrochemical impedance analyzer (EIS).

DCM2와 Rubrene이 첨가된 발광층 위치에 따른 적색 OLED의 발광 특성

정행윤,구할본,Jung, Haeng-Yun,Gu, Hal-Bon 한국전기전자재료학회 2011 전기전자재료학회논문지 Vol.24 No.8

In this study, we have fabricated the red OLED (organic light emitting diode). The basic device structure is ITO/hole transporting layer, TPD(500 $\AA$)/red emitting layer, Alq3 doped with DCM2:rubrene(20 $\AA$)/electron transporting layer, Alq3(M) (500 $\AA$-M $\AA$)/LiF(15 $\AA$)/Al(1,000 $\AA$). The thickness of electron transporting layer(500 $\AA$-M $\AA$) changed 0, 20, 40, 60 $\AA$. Turn on voltage of the red OLED was 5 V, 6 V, 6.5 V and 7.5 V, respectively with electron transfer layer changed ratio. Luminance of red OLED was 4,504, 1,840, 1,490 and 1,130 cd/$m^2$, respectively. Optimized electron transfer layer position changed ratio of the red OLED was 0 $\AA$.

은 나노 입자를 이용한 염료감응형 태양전지의 효율 향상 효과

정행윤,홍경진 한국전기전자재료학회 2018 전기전자재료학회논문지 Vol.31 No.1

In this study, e-beam equipment was used to form silver nanoparticles on thin films of TiO2 to increase theefficiency of dye-sensitized solar cells and improve the annealing process. TiO2 thin films with nanoparticlephotoelectrodes were fabricated in individual units for use in dye-sensitized solar cells. The characteristics ofdye-sensitized solar cells were compared to those of the prepared TiO2 photoelectrode with and without nanoparticles. The dye-sensitized solar cells with silver nanoparticles showed a significant increase in the electric current densitycompared with the pure TiO2 dye-sensitized solar cell and improved the solar conversion efficiency to 27.89%. Theincreased density of electric current increased the extent of light absorption of the dye owing to the plasmon resonanceof the nanoparticles at the local surfaces. This phenomenon led to increased light scattering, which in turn increased thecurrent density of the dye-sensitized solar cells and improved the solar conversion efficiency. 본 연구에서는 염료감응형 태양전지의 광전변환효율을 증가시키기 위해 TiO2 박막 위에 은 나노 입자를 형성하고자 E-beam 장비를 이용하였고, 어닐링 공정을 진행하였다. 은 나노 입자들이 형성된 TiO2 박막을 광전극으로 사용하였으며 염료감응형 태양전지 단위 셀을 제작하였다. 은 나노 입자들이 포함 된 TiO2 광전극과 순수한 TiO2 광전극을 사용한 염료감응형 태양전지를 비교하여 특성을 분석하였다. 은 나노 입자들이 포함 된 염료감응형 태양전지는 순수한 TiO2 염료감응형 태양전지에 비해 전류 밀도의 상당한 증가를 가져왔으며 광전변환효율이 최대 27.89% 개선되는 것으로 나타났다. 전류 밀도의 증가는 은 나노 입자들의 국소적 표면 플라즈몬 공명으로 인한 염료의 광흡수를 증가시켜 광 산란의 강화로 인해 염료감응형 태양전지의 전류밀도와 광전변환효율을 증가시켰다.

바인더 함량에 따른 염료감응 태양전지의 효율에 관한 연구

기현철,정행윤,구할본,Ki, Hyun-Chul,Jung, Haeng-Yun,Gu, Hal-Bon 한국전기전자재료학회 2013 전기전자재료학회논문지 Vol.26 No.12

In this study, we have fabricated the dye sensitized solar cell (DSSC) composed by a transparent conductive oxide (TCO), a nanocrystalline semiconductor film usually $TiO_2$, a sensitizer adsorbed on the surface of the semiconductor, an electrolyte containing a redox mediator and a counter electrode. The $TiO_2$ nanopowder was prepared by sol-gel methode. The HCl (hydrochloric acid) and TBAOH (Tetrabutyl amonium hydroxide) was added for improving the catalyst and distributed properties of $TiO_2$ nanopowder. Ammonium hydroixde was added in order to control the morphology and size of $TiO_2$ nano crystal. A $TiO_2$ paste for working electrode was prepared with the addition of HPC (hydroxypropyl cellulos) used as a binder of which volume was controled as 1.3, 1.5, 1.7, and 2.0%. The measured I-V curves of assembled DSSC showed that the cell with 1.7% HPC binder had the best efficiency of 6.79%.

염기성 촉매제를 이용한 염료감응 태양전지의 효율에 관한 연구

기현철,정행윤,구할본,Ki, Hyun-Chul,Jung, Haeng-Yun,Gu, Hal-Bon 한국전기전자재료학회 2013 전기전자재료학회논문지 Vol.26 No.10

In this study, the influence of electrochemical properties by mixing Tetrabutylammonium hydroxide (TBAOH) and ammonium hydroxide (NH4OH) electrode on the dssc. The titanias were prepared using a sol-gel method by mixing Tetrabutylammonium hydroxide and Ammonium hydroxide. The $TiO_2$ nanopowder prepared by sol-gel methode, and to improve the distributed properties of $TiO_2$ nanopowder, the TBAOH and NH4OH was added. The I-V values of cells show that the Tetrabutylammonium has 6.51% efficiency.

수질 측정용 플로우 셀의 오염 모니터링을 위한 평면광도파로 센서

한승헌,김태언,정행윤,기현철,김두근,김선훈 한국전기전자재료학회 2019 전기전자재료학회논문지 Vol.32 No.6

본 연구에서는 광학 기반 수질 측정 시스템의 플로우 셀의 오염 정도를 모니터링 할 수 있는 평면광도파로(PLC, planar lightwave circuit)를 이용한 광학 센서를 제안하였다. 현장 및 실시간 수질 측정 시스템의 플로우 셀 오염으로 인한 측정 오차를 보정할 수 있을 뿐만 아니라 플로우 셀 자체의 유지보수 시기를 결정하는 데 활용할 수 있는 V자형 광도파로를 갖는 PLC 센서를 실리카 기반으로 설계 및 제작하였다. FDTD (finite-difference time-domain) 방법을 이용하여 PLC 센서의 감지 영역 부분의 오염을 가정하여, 오염에 따른 광 전송 특성 변화를 수치 해석 하였다. 또한, 실제 PLC 센서를 통해 플로우 셀의 오염 모니터링이 가능한지 확인하기 위하여, PLC 센서가 설치된 플로우 셀에 수돗물을 채우고 장기간 PLC 센서의 광 전송 손실 변화를 관찰하였다. PLC 센서가 수돗물에 침지된 일 수가 증가할수록 PLC 센서의 광 전송 강도가 감소하였으며, 광 전송 강도가 1.55 μm에서 3 dB 만큼 감소한 침지 일 수는 약 15일이였다. We have proposed a novel planar lightwave circuit (PLC) optical sensor to monitor the contamination in a flow-cell where water is continuously supplied through a water quality measurement system. We designed a PLC chip with a V-shape waveguide and the simulated its function as a sensor for monitoring contamination in a flow-cell using a numerical the FDTD (finite-difference time-domain) analysis. A novel cross type of waveguide was introduced to make the PLC chip of the V-shaped waveguide. The fabricated PLC was cut into the cross waveguide. A change in the optical propagation loss of the PLC sensor was observed after immersing the PLC sensor into city water. It was determined that the propagation loss of the PLC sensor was 3 dB at a wavelength of 1.55 μm in the city water for 15 days.

펄스 레이저 기반 담수용 미세 플라스틱 실시간 센서 모니터링 시스템 연구

한승헌,김선훈,김대근,정행윤 한국센서학회 2019 센서학회지 Vol.28 No.5

Pulsed laser-based optical sensor monitoring systems for real time microplastic particle counting are proposed and developed in this study. To develop our real time monitoring system, we used a 450 nm pulsed laser and a photomultiplier with very high quantum efficiency. First, we demonstrated that the microplastic particle counting system could detect standard micro bead samples of 100, 250, and500 µm in river water. We then performed research concerning pulsed laser-based optical spectral sensor systems for real time microplastic monitoring. Additionally, we demonstrated that the real time microplastic remote monitoring system using LoRa communications could detect microplastic in the tap water resource protection area.