以銀/二氧化鈦奈米複合結構提升染料敏化太陽能電池效率

Enhanced Conversion Efficiency of Dye-sensitized Solar Cell by Utilizing Ag/TiO2 Composite Nanostructures

張景星(Ching-hsing Chang)

指導教授 ： 李勝偉

國立中央大學/工學院/材料科學與工程研究所/碩士(2012年)

摘要

本研究主要利用銀/二氧化鈦奈米複合結構，應用於染料敏化太陽能電池(DSSC)陽極部分，我們利用旋轉塗部法將二氧化鈦奈米粒子 (TiNPs)覆蓋在FTO上，用來組裝染料敏化太陽能電池參考電池，更進一步地加上銀/二氧化鈦奈米複合結構，提升染料敏化太陽能電池效率。並藉由SEM、XRD、Raman、UV-VIS、TEM、XPS來進行材料分析。接著將實驗中所製備完成的二氧化鈦奈米複合結構進行染料敏化太陽能電池組裝，並進一步地利用太陽光模擬器量測系統、入射光電轉換效率系統 (IPCE)，去量測其太陽能電池的效率與入射光電轉換效率。由這些二氧化鈦奈米複合結構可分為三大部分。
第一部分為添加二氧化鈦奈米管 (TiNTs)對於效率的影響，研究結果顯示，在加入二氧化鈦奈米管之後效率2.58%提升至2.80%，效率提升其主要原因為陽極厚度增加，可使染料吸附量變高，因此提升了效率。第二部分探討在二氧化鈦奈米管上鍍一層10nm的銀粒子，想利用銀粒子在表面電漿共振的效應，使電池效率增加，從實驗數據顯示再添加銀粒子之後幾乎有明顯的提升。第三部分討論將二氧化鈦奈米結構浸泡飽和的硝酸鋇溶液，使得二氧化鈦表面可以形成鈦酸鋇，由於鈦酸鋇有較高的等電點，可使染料吸附量變高。因此將三個想法結合在一起，製備出BaTiO3/Ag/TiNT/TiNP結構與BaTiO3/TiNT/Ag/TiNP太陽能電池效率分別提升至3.31%與3.07%。

關鍵字

染料敏化太陽能電池 ； 二氧化鈦

並列摘要

In this study, the Ag/TiO2 composite nanostructures were utilized as the photoanode in dye-sensitized solar cells (DSSC). For the reference cell, the titanium dioxide nanoparticles (TiNPs) was coated onto the FTO substrate by spin coating technique. The Ag/TiO2 composite nanostructures were applied to enhance the conversion efficiency of the DSSC. The material characteristics were analyzed by SEM, XRD, TEM, XPS, vmicro-Raman and UV-Vis measurements. The cells were then assembled an their I-V characteristics and incident photo conversion efficiency (IPCE) were measured by using the sunlight simulator measurement system.
The nanocomposite structures were implemented into DSSC in three ways. The first way is to introduce titanium dioxide nanotubes (TiNTs) into the DSSC. The results show that the efficiency was increased from 2.58% to 2.80% by increasing the photoanode thickness. It allows the dyes to be highly adsorbed, thus enhancing the conversion efficiency. The second way is to deposit silver particles acting as surface plasmons in DSSC. The cell efficiency was found to improve significantly as compared to the reference cell. The third way is by soaking the TiNT in saturated barium nitrate solution, modifying the TiNT surface by forming barium titanate. The efficiency was further enhanced. It was speculated that the dyes was highly adsorbed due to the higher isoelectric point of barium titanate. The integration of the DSSC with the BaTiO3/Ag/TiNT/TiNP and BaTiO3/TiNT/Ag/TiNP structures increased the solar cell efficiency up to 3.31% and 3.07%, respectively.

並列關鍵字

titanium dioxide ； dye-sensitized solar cell

參考文獻

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