溶膠凝膠法搭配原子層沉積術製作多孔二氧化鈦散射層以提升染料敏化太陽能電池性能之研究

Study on the Improved Performance of Dye-Sensitized Solar Cells by a Porous Titanium Dioxide Scattering Layer Obtained by a Sol-Gel Method and Atomic Layer Deposition

俞習文(Hsi-Wen Yu)

指導教授 ： 卓君珮

國立暨南國際大學/科技學院/應用材料及光電工程學系/碩士(2019年)

摘要

本研究使用溶膠凝膠法製備TiO2多孔膜作為光陽極散射層，可增加光吸收及改善轉換效率。藉由調整PVP的含量，可控制多孔膜之孔洞密度及孔徑大小，經實驗發現使用1.5 g之PVP溶膠凝膠所製成之多孔膜擁有最佳孔洞密度。
本研究亦使用原子層沉積技術鍍覆TiO2或Ta2O5金屬氧化薄膜於光陽極表面，透過調控前驅物注入及氮氣吹掃之時間與循環數設定，可調整鍍膜之厚度，此製程可以填補光陽極各層間的缺陷，以獲得更佳轉換效率。由實驗結果發現以原子層沉積技術鍍上7 nm之TiO2或5 nm Ta2O5，分別可以得到最高7.13 %及6.53 %之轉換效率。經由電化學分析，可由奈奎斯特圖、波德圖、交流阻抗等實驗結果，可得知原子層沉積技術對電荷傳遞及元件特性的影響。

關鍵字

多孔二氧化鈦 ； 散射層 ； 原子層沉積 ； 五氧化二鉭 ； 染料敏化太陽能電池

並列摘要

The TiO2 porous films obtained by a facile sol-gel method were applied to the photoanodes of DSSCs as the scattering layer, which was found to increase reuse of the incident light and thus improved energy conversion efficiency. By changing the content of PVP in the sol-gel solution, the pore density could be tuned. The optimum density was achieved when the amount of PVP was 1.5 g.
Moreover, an ultra-thin TiO2 or Ta2O5 film covering the porous film was achieved by ALD. By adjusting the pulse time and purge time of ALD, the defects on the surface of a photoanode were decreased. The highest efficiency, 7.13 % and 6.53 %, were achieved when the thicknesses of TiO2 and Ta2O5 by ALD was 7 nm and 5 nm, respectively. The electrochemical experiments for acquiring Nyquist plots, Bode plots and interfacial impedances, were also performed to investigate the charge transfer and device performance affected by various ALD conditions.

並列關鍵字

Porous titanium dioxide ； scattering layer ； atomic layer deposition (ALD) ； tantalum pentoxide ； dye-sensitized solar cell (DSSC)

參考文獻

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