製作於不鏽鋼基板之染料敏化太陽能電池與有機發光二極體特性研究

Fabrication and Characterization of On-Stainless Steel Dye-Sensitized Solar Cells and Organic Light-Emitting Diodes

陳永斌(Yung-Bin Chen)

指導教授 ： 陳奕君

國立臺灣大學/電機資訊學院/光電工程學研究所/碩士(2011年)

https://doi.org/10.6342/NTU.2011.02124

摘要

本研究主要是以不鏽鋼箔作為可撓性基材，分別應用於光轉電-染料敏化太陽能電池(DSSC)-及電轉光-有機發光二極體(OLED)-等兩種元件，探討各樣實驗條件如不鏽鋼箔之表面粗糙度對於元件輸出特性之效應。
第一部份利用不鏽鋼箔搭配商用TiO2漿料、N719染料及液態電解質，及商用之導電塑膠基材ITO-PET濺鍍白金作為對電極，製作成以不鏽鋼為光電極基底之可撓性TiO2染料敏化太陽能電池(DSSCs)，並觀察不鏽鋼箔的種類、不鏽鋼箔表面粗糙度、多孔隙TiO2層厚度等條件的差異，對於DSSC輸出特性的影響。藉由濺鍍Ti金屬或蒸鍍TiO2薄膜於不鏽鋼箔表面，其結果顯示均可有效提升元件之效能，表示其有效地抑制了電荷與電解液發生逆向複合的機會，此外SUS 430之熱膨脹係數低於其它不鏽鋼箔(如SUS 316L)，故若製程條件相同，以SUS 430作為光電極基板製作成DSSC之光電轉換效率亦較高。在入射光強度100mW/cm2之下，SUS 430光電極基底之DSSC最佳光電轉換效率為1.04%，而SUS 316L基底DSSC則以1.10%為最佳值。此外，對於SUS 316L基底DSSC來說，多孔隙TiO2層於厚度3.5μm以下時光電流隨著基板表面粗糙度增加而提升，超過此厚度則無明顯趨勢。多孔性TiO2層厚度為8~11μm達最佳效能。
第二部份是利用前述之不鏽鋼箔作為基板，先旋塗一層高分子材料benzo- cyclobutene (BCB)作為絕緣性之平坦化層，再將有機發光二極體(OLEDs)製作於其上，結構為ITO/NPB/Alq3/Cs2CO3(或LiF)/Al，並以鍍有SiO2防水氧層之PET塑膠膜將其封裝。結果顯示可撓式OLED於彎曲前後其I-V特性沒有變化；基板的粗糙度使OLED產生暗點，而氣體的滲透更是封裝後OLED劣化的主因。

關鍵字

不鏽鋼基板 ； 染料敏化太陽能電池 ； 有機發光二極體

並列摘要

In this study, the stainless steel (StSt) foils were applied as flexible substrates for dye-sensitized solar cells (DSSCs) and organic light-emitting diodes (OLEDs). The relationships between various factors and device performances were investigated.
In the first part, porous TiO2 film was fabricated on a StSt substrate by doctor-blade method. To prevent charge recapture by I3-, a evaporated TiO2 film or sputtered Ti film was deposited on StSt surface prior to the fabrication of porous TiO2 film. Then, the sintering of porous TiO2 was taken place at 450℃. Afterwards, the TiO2 electrodes were immersed in N719 dye solution, and assembled with Pt-coated ITO-PET. At last, liquid electrolyte was injected into the assembled cells. The effects of types of StSt, surface roughness of StSt and thickness of porous TiO2 films on the performances of DSSC were studied. Under 100 mW/cm2 (AM1.5) simulated light, the optimal conversion efficiency was 1.04% for SUS 430-based DSSC, and 1.10% for SUS 316L-based DSSC. For SUS 316L-based DSSC, the photocurrent of cells with porous TiO2 layer thickness less than 3.5 μm increased with surface roughness of the substrate. However, for cells with porous TiO2 layer thicker than 3.5 μm, degraded cell performance was observed, which may attribute to the large mismatch of the coefficients of thermal expansion between the StSt substrate and the TiO2 film. Optimal performance was obtained when the porous TiO2 film was about 8~11 μm.
In the second part, A steel-based flexible OLED was fabricated with a configuration of StSt/BCB/ITO/NPB/Alq3/ Cs2CO3(or LiF)/Al. Spin-coated BCB was used as a planarization layer. The OLED was then encapsulated with a SiO2-coated PET film. The device exhibited similar I–V characteristics under bending.

並列關鍵字

Stainless steel substrate ； DSSC ； OLED

參考文獻

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