二氧化鈦塑膠電極製備參數對染料敏化太陽能電池效率的影響

Effect of preparatory conditional of plastic TiO2 electrode on the performance of dye-sensitized solar cells

劉育杰(Yu-Jie Liu)

指導教授 ： 陳龍泉

崑山科技大學/工程學院/材料工程研究所/碩士(2012年)

https://doi.org/10.6828/KSU.2012.00084

摘要

本研究利用刀刮法塗佈二氧化鈦漿料於銦錫氧化物/聚萘二甲酸乙二酯(ITO/PEN)上，利用機械壓力製作二氧化鈦光陽極，並與白金電極組裝成染料敏化太陽能電池(DSSC)，討論漿料球磨時間、機械壓力大小、熱壓溫度及真空前處理對電極薄膜性質及DSSC效能的影響。採用的二氧化鈦包括商業化P25以及利用水熱法自製的小粒徑及大粒徑二氧化鈦。
在沒有機械壓力時，增加球磨時間會降低漿料中二氧化鈦的顆粒粒徑，增加表面OH官能基，有助於提升薄膜的表面平整性，及增加光電轉換效率；但若同時提升薄膜機械壓力，則有最適的的球磨時間及壓力組合，大於此壓力或球磨時間，染料溶液無法滲透進入薄膜內部進行吸附。系統顯示商業品P25以150 rpm球磨10分鐘，機械壓力100 MPa製得的薄膜，在測試的條件下，有最大的吸光行為及光電轉換效率。
相對而言，摻雜自製大顆粒二氧化鈦，若機械壓力為100 MPa，則最適的球磨時間為60分鐘，可得最高的光電轉換效率。在60-100℃的熱壓溫度中，80℃顯示最佳的薄膜品質，60℃時薄膜顆粒連結性低，會有顆粒脫落的情形，100℃時由於薄膜內水分於機械壓置時快速氣化，薄膜易龜裂。熱壓前適當的真空處理薄膜內的水分，可提升薄膜品質，提升光電轉換效率。利用開路電壓衰退方法計算之電子壽命顯示在高光電壓區域，電子壽命會隨光電壓的增加而有下降的趨勢。

關鍵字

染料敏化太陽能電池 ； 二氧化鈦 ； 機械壓製 ； 球磨 ； 電子壽命 ； 塑膠陽極

並列摘要

TiO2 paste prepared by ball milling was coated onto ITO-PEN plastic substrates by doctor blade and mechanical compression techniques to form TiO2 photoanodes of dye sensitized solar cells with platinum counter electrodes. The influence of ball milling time, pressure and temperature of mechanical compression, and vauuum pretreatment on the characteristics of titanium dioxide films and perfromance of the DSSCs was investigated in this study. Commercially available P25 and home-made TiO2 with various particle sizes were used as precursors.
Without compression, increasing ball milling time can increase OH group quantity and reduce the particle size of TiO2, causing a more flat surface of TiO2 films and a higher photo-to-electricity conversion efficiency. With compression, there exists an optimum ball milling time and compression pressure for high conversion efficiency because a close compact film structure would retard the percolation of dye solution.
With a compression pressure of 100 MPa at room temperature and a ball milling time of 10 min at 150rpm yields the highest photo-to-electricity conversion among the parameters evaluated for P25 TiO2. For a home-made TiO2 with larger particle size (around 90 nm), the optimum ball milling time and compression presure were 60 min and 100 MPa, achieving the highest converison efficiency. Heat compression at 80℃ can significantly enhance the photo-to-electricity conversion efficiiency when compared with those of 60 and 100℃. A 20 min vacuum pretreatment can improve the film property via reduction of water molecules within the film. At high photovoltage region, the electron lifetime decreases with increasing photovoltage according the open circuit volatge decay measurement.

並列關鍵字

dye sensitized solar cells ； titanium dioxide ； mechanical compression ； ball milling ； electron lifetime ； plastic anode

參考文獻

[2]聯合國氣候變化綱要公約的京都議定書聯合國氣候變

Convention on Climate Change

化綱要公約（United Nations Framework Convention on

25, 676, 1954.

[14]S.O. Kasap, Optoelectronics and Photonics: Principles and Practices, Prentice-Hall, 2001.