Journal of the Korea Academia-Industrial cooperation Society (한국산학기술학회논문지)

The Korea Academia-Industrial cooperation Society (한국산학기술학회)
권호 표지
DOI QR코드

DOI QR Code

Degradation of a nano-thick Au/Pt bilayered catalytic layer with an electrolyte in dye sensitized solar cells

염료감응태양전지의 Au/Pt 이중 촉매층의 전해질과의 반응에 따른 열화

  • Noh, Yunyoung (Department of Materials Science and Engineering, University of Seoul) ;
  • Song, Ohsung (Department of Materials Science and Engineering, University of Seoul)
  • 노윤영 (서울시립대학교 신소재공학과) ;
  • 송오성 (서울시립대학교 신소재공학과)
  • Received : 2014.02.25
  • Accepted : 2014.06.12
  • Published : 2014.06.30
Download PDF
⟨ Previous Next ⟩

Abstract

A 0.45 $cm^2$ DSSC device with a glass/FTO/blocking layer/$TiO_2$/N719(dye)/electrolyte/50 nm-Pt/50 nm-Au/FTO/glass was prepared to examine the stability of the Au/Pt bilayered counter electrode (CE) with electrolyte and the energy conversion efficiency (ECE) of dye-sensitized solar cells (DSSCs). For comparison, a 100 nm-thick Pt only CE DSSC was also prepared using the same method. The photovoltaic properties, such as the short circuit current density ($J_{sc}$), open circuit voltage ($V_{oc}$), fill factor (FF), and ECE, were checked using a solar simulator and potentiostat with time after assembling the DSSC. The microstructure of the Au/Pt bilayer was examined by optical microscopy after 0~25 minutes. The ECE of the Pt only CE-employed DSSC was 4.60 %, which did not show time dependence. On the other hand, for the Au/Pt CE DSSC, the ECEs after 0, 5 and 15 minutes were 5.28 %, 3.64 % and 2.09 %, respectively. The corrosion areas of the Au/Pt CE determined by optical microscopy after 0, 5, and 25 minutes were 0, 21.92 and 34.06 %. These results confirmed that the ECE and catalytic activity of Au/Pt CE decreased drastically with time. Therefore, a Au/Pt CE-employed DSSC may be superior to the Pt only CE-employed one immediately after integration of the device, but it would degrade drastically with time.

염료감응형 태양전지 상대전극부에 Au/Pt 이중 촉매층 적용에 따른 전해질과의 반응안정성 확인과 에너지변환효율 변화를 확인하기 위해 $0.45cm^2$ 면적을 가진 glass/FTO/blocking layer/$TiO_2$/dye/electrolyte/50nm Pt/50nm Au/glass 구조의 소자를 준비하였다. 비교를 위해 평탄한 유리기판 위에 증착된 100nm 두께의 Pt 상대전극을 채용한 소자도 동일한 방법으로 확인하였다. 솔라 시뮬레이터와 퍼텐쇼 스탯을 통해 단락전류밀도, 개방전압, 필팩터, 에너지변환효율의 광전기적 특성을 확인하였다. Au/Pt 이중층과 전해질의 반응을 확인하기 위해 광학현미경을 통해 전해질 주입 후 0~25분 후 이중층의 미세구조를 확인하였다. 광전기적 특성 분석 결과, 평탄한 유리기판 위의 단일층 Pt의 에너지변환효율은 4.60%를 나타내고 시간 의존성이 없었다. 반면, Au/Pt의 경우 전해질 주입 직 후, 5분 후, 25분 후의 에너지 변환 효율이 각각 5.28%, 3.64%, 2.09%로 시간이 지남에 따라 감소하였다. 광학현미경 분석을 통하여, 전해질 주입 직 후, 5분 후, 25분 후의 부식면적이 각각 0, 21.92, 34.06%로 Au와 전해질이 반응하여 부식되는 것을 확인하였고, 이를 통해 Au/Pt가 전기적으로 시간이 지남에 따라 촉매활성도와 효율이 감소하는 것을 확인하였다. 따라서 염료감응태양전지에 Au/Pt 촉매는 단기적으로는 기존 Pt only보다 우수하였으나 장기적으로는 전해질과의 안정성이 미흡함을 확인하였다.

Keywords

References

  1. M. Gratzel, "Solar Energy Conversion by Dye-Sensitized Photovoltaic Cells", Inorg. Chem. 44, pp. 6841-6851, 2005. DOI: http://dx.doi.org/10.1021/ic0508371
  2. Y. Ooyama, Y. Harima, "Molecular Designs and Syntheses of Organic Dyes for Dye-Sensitized Solar Cells", Org. Ch em. 18, pp. 2903-2934, 2009. DOI: http://dx.doi.org/10.1002/ejoc.200900236
  3. B. O'Reagan, M. Gratzel, "A low-cost, high-efficiency sol ar cell based on dye-sensitized colloidal TiO2 films", Nature 353, pp. 737-740, 1991. DOI: http://dx.doi.org/10.1038/353737a0
  4. M. Adachi, Y. Murata, J. T. Kao, J. T. Jiu, M. Sakamoto, F. M. Wang, "Highly efficient dye- sensitized solar cells with a titania thin-film electrode composed of a network structure of single-crystal-like $TiO_2$ nanowires made by the oriented attachment mechanism", J. Am. Chem. Soc. 126, pp. 14943-14949, 2004. DOI: http://dx.doi.org/10.1021/ja048068s
  5. S. Ngamsinlapasathian, S. Sakulkhaemaruethai, S. Pavasup ree, A. Kitiyanan, T. Sreethawong, Y. Suzuki, and S. Yos hikawa, "Highly efficient dye-sensitized solar cell using n anocrystalline titania containing nanotube structure", J. P hotochem. Photobiol. A Chem. 164, pp. 145-151, 2004. DOI: http://dx.doi.org/10.1016/j.jphotochem.2003.11.016
  6. K. J. Hwang, W. G. Shim, S. H. Jung, S. J. Yoo, J. W. Lee, "Analysis of Adsorption Properties of N719 Dye Mole cules on Nanoporous TiO2 Surface for Dye-Sensitized Sol ar Cell", Applied Surface Science 17(15), pp. 5428-5433, 2010. DOI: http://dx.doi.org/10.1016/j.apsusc.2009.12.128
  7. Y. Noh, K. Yoo, M. J. Ko, O. Song, "Dye-Sensitized Solar Cells Employing Laser Patterned Counter Electrodes", Korean J. Met. Mater. 51(3), pp. 239-243, 2013. https://doi.org/10.3365/KJMM.2013.51.3.239
  8. Y. Noh, O. Song, "Dye-Sensitized Solar Cells for Rutheniu m Counter Electrodes Employing Polystyrene Beads and ZnO", Korean J. Met. Mater. 51(12), pp. 901-905, 2013. DOI: http://dx.doi.org/10.3365/KJMM.2013.51.12.901
  9. Y. Noh, O. Song, "Properties of the Nano-Thick Al/Pt or Ti/Pt Bilayered Catalytic Layer Used in Dye Sensitized S olar Cells", Korean J. Met. Mater. 52(1), pp. 61-65, 2014. DOI: http://dx.doi.org/10.3365/KJMM.2014.52.1.061
  10. Y. Noh, O. Song, "Properties of the nano-thick Pt/W bilay ered catalytic layer employed dye sensitized solar cells", Electron. Mater. Lett. 10(3), pp. 627-630, 2014 DOI: http://dx.doi.org/10.1007/s13391-013-3257-1
  11. Y. J. Suh, S. Y. Park, T.H. Lee, W. S. Chung, K. K. Kim, M. J. Kim, "TEM Study of Stability of Inverted Photovolt aic (PV) Cells", Microscopy and Microanalysis 16, pp. 1378-1379, 2010. DOI: http://dx.doi.org/10.1017/S1431927610062057
  12. Y. Noh, O. Song, "Degradation of the Pd catalytic layer electrolyte in dye sensitized solar cells", Journal of the Ko rea Academia-Industrial cooperation Society 14(4), pp. 20 37-2042, 2013. DOI: http://dx.doi.org/10.5762/KAIS.2013.14.4.2037
  13. Y. Noh, O. Song, "Properties of The Cu/Pt Bilayered Counter Electrode Employed Dye Sensitized Solar Cells", Korean J. Met. Mater. in press, 2014 DOI: http://dx.doi.org/10.3365/KJMM.2014.52.3.237
  14. Y. Noh, O. Song, "Properties of an Au/Pt Bilayered Counter Electrode in Dye Sensitized Solar Cells", Electron. Mater. Lett. in press, 2014 DOI: http://dx.doi.org/10.1007/s13391-013-3043-0
  15. M. Mavrikakis, B. Hammer, "Effect of Strain on the Reactivity of Metal Surfaces", J. K. Norskov, Phys. Rev. Lett. 81, pp. 2819-2822, 1998. DOI: http://dx.doi.org/10.1103/PhysRevLett.81.2819
  16. L. Andrade, J. Sousa, H. A. Ribeiro, A. Mendes, "Phenomenological modeling of dye-sensitized solar cells under transient conditions", Solar Energy 85, pp. 781-793, 2011. DOI: http://dx.doi.org/10.1016/j.solener.2011.01.014