電化學沉積氧化鋅薄膜應用於可撓式染料敏化太陽能電池之研究

Electrochemical deposition of Zinc Oxide Thin Films and Their Application to Flexible Dye-Sensitized Solar Cells

林峻民(Chun-Min Lin)

指導教授 ： 余琬琴

國立臺北科技大學/工程學院/有機高分子研究所/碩士(2012年)

https://doi.org/10.6841/NTUT.2012.00628

摘要

本研究以電化學沉積法製備二維氧化鋅奈米片結構，並將其製成染料敏化太陽能電池的工作電極。探討的因子包括電沉積通氧條件、染料種類與膜厚，使用的基板包括玻璃基板與可撓式鈦基板，在鈦基板方面，並探討表面處理對背照式電池效率的影響，基板表面處理方式包含雙氧水處理、拋光處理與高溫鍛燒(500℃)處理，未處理的鈦基板則為對照組，低溫鍛燒的時間則是從1 至24小時。
研究結果顯示，電鍍液通氧經由電化學沉積所得的奈米片是由氧化鋅前驅物構成，該奈米片大多直立於基板上，且相互連結形成網狀結構，並不會改變其形貌。經低溫鍛燒(150℃)後，該前驅物轉化成氧化鋅，而且奈米片上出現許多微小的孔洞。此多孔結構具有高的比表面積，而且直立的奈米片利於電子的傳輸，適合應用於染料敏化太陽能電池。為了決定最佳的鍛燒時間，我們先固定膜厚(9 μm)，變化鍛燒時間。結果顯示電沉積通氧條件成功縮短了最佳低溫鍛燒時間，從原本24小時縮短至12小時，在此薄膜厚度(9 μm)下，光電轉換效率可達2.43%。接著，我們固定鍛燒時間(12小時)，改變不同染料種類與膜厚。結果顯示，有機釕金屬染料N719敏化下，最佳膜厚為26 μm，光電轉換效率可達3.93%；有機小分子染料D149敏化下，最佳膜厚為15 μm，光電轉換效率可達3.91%。
在鈦基板方面，我們將多孔性奈米片陣列的製備方法應用於鈦基板，鈦板具有低電阻、彈性佳及可撓式的特性，適用於可撓式染料敏化太陽能電池的製備。結果顯示雙氧水與拋光處理之光電轉換效率、光電流密度及填充因子均明顯高於高溫處理與未處理。採雙氧水處理，最佳膜厚為35 μm，背照式光電轉化效率可達2.2%。

關鍵字

染料敏化太陽能電池 ； 電化學沉積 ； 氧化鋅 ； 奈米片 ； 鈦基板

並列摘要

In this study ZnO nanoporous films were prepared by using the electrochemical deposition method with oxygen bubbling and fabricated into DSSC photoanodes. The factors investigated included electrodeposition with oxygen bubbling and low-temperature calcination time, organic and inorganic complexes dyes and thickness of the relationship between, flexible titanium substrate surface treatment on the back-illuminated cell efficiency. the choice of three different surface treatments, respectively, hydrogen treatment, polished and high-temperature sintering process, the titanium substrate, compared with untreated control group. The calcination time at 150℃ was varied from 1 to 24 hours.
The results show that the as-deposited precursor nanosheets were roughly vertically aligned with the glass substrate and formed a connecting network with space between them. Calcination at 150℃not only converted the precursor into ZnO, but also generated numerous through pores on the nanosheets. Such a structure should be favorable for photoanode construction, because the porous nanosheets provide a relatively large surface area for dye adsorption, and the vertically standing nanosheets give a direct conduction pathway for electron transport. In order to determine the optimal calcination time at 150℃, the calcination time was varied from 1 to 24 h, while the thickness of the ZnO nanoporous film was maintained at 9 μm. A calcination time of 12 h was found to be optimal, and the highest conversion efficiency achieved with the 9 μm film was 2.43%. The results show the power deposition in oxygen conditions successfully shortened the best low-temperature calcination time shortened from 24 hours to 12 hours. In order to further improve the conversion efficiency, the effect of film thickness on cell efficiency was investigated. The highest conversion efficiency of 3.93% was obtained at a film thickness of 21 μm in inorganic dye-sensitized. The highest conversion efficiency of 3.91% was obtained at a film thickness of 15 μm in organic dye-sensitized.
The ZnO nanoporous films were prepared by using the electrochemical deposition method with oxygen bubbling in the titanium substrate, titanium has a low resistance, good flexibility and flexible features, suitable for the preparation of flexible dye-sensitized solar cells. The results showed that the photoelectric conversion efficiency of hydrogen treatment and polished, the photocurrent density and fill factor were significantly higher than the high temperature treatment and untreated. The highest back-illuminated type photoelectric conversion efficiency of 2.2% was obtained at a film thickness of 35 μm in hydrogen treatment.

並列關鍵字

dye-sensitized solar cells ； electrochemical deposition ； ZnO ； nanosheet ； titanium substrate.

參考文獻

72. 蔡季洋，氧化鋅奈米片的製備及其在染料敏化太陽能電池之應用，碩士論文，國立台北科技大學，台北， 2011。

1. J. Pelly, “Solar cells that harness infrared light”, Environmental Science and Technology, 39, 2005, 151A-152A.

2. T. Z. Ramon, E. Jamil, L. C. Claude, B. Chegnui, V. Tobias, M. S. Iván and B. Juan, “Influence of the potassium chloride concentration on the physical properties of electrodeposited ZnO nanowire arrays”, J. Phys. Chem. C, 112, 2008, 16318-16323.

3. C. H. Lee, W. H. Chiu, K. M. Lee, W. F. Hsieh, J. M. Wu, “Improved performance of flexible dye-sensitized solar cells by introducing an interfacial layer on Ti substrates”, J. Mater. Chem., 21, 2011, 5114-5119.

4. M. Grätzel, “Photoelectrochemical cells”, Nature, 414, 2001, 338-344.