改善染料敏化太陽能電池的長期穩定性及劣質化現象之研究

Long-term Stability and Degradation Mechanisms of Dye Sensitized Solar Cells with Nitrogen Doped TiO2 and Bis-benzimidazole Derivative Additives

呂鴻臨(Hung-Lin Lu)

指導教授 ： 楊重光

國立臺北科技大學/工程學院/工程科技研究所/博士(2013年)

摘要

水造成染料敏化太陽能電池的劣質化現象以及衰減電池的長期穩定性。如果利用適當的添加劑或者二氧化鈦的改質可以降低染料敏化太陽能電池的劣質化現象及延長電池的壽命。本文研究第一部分同位素水(H2O、 D2O、H218O)對於電池劣質化的影響，結果發現同位素水對於電池劣質化速率有所不同。其劣質化速率為: H2O > D2O > H218O。第二部分利用苯並咪唑衍生物做為染料敏化電池之添加劑加入電解液，電池電壓以及長期穩定性皆有所改進。藉由加入苯並咪唑衍生物之添加劑可以有效阻擋LiNCS吸附在二氧化鈦表面上以及降低再結合現象的產生。第三部分則利用二氧化鈦摻雜氮做為染料敏化太陽能電池之工作電極可以增加電池電流以及改善長期穩定性。利用紅外光譜儀可發現二氧化鈦摻雜氮有較低的表面吸水能力。使得二氧化鈦摻雜氮之電池的效率在六個月後，二氧化鈦摻雜氮之電池的效率下降至六個月前的25%，而二氧化鈦不摻雜氮之電池的效率下降至原先的10%，擁有較高的電流與效率表現。在未來，希望將苯並咪唑衍生物的添加劑以及二氧化鈦摻雜氮之工作電極合併做成太陽能電池，同時提升電池之電壓、電流以及長期穩定性。

關鍵字

劣質化 ； 長期穩定性 ； 水 ； 二氧化鈦摻雜氮 ； 染料敏化太陽能電池

並列摘要

The presence of water in DSSC concerns the role of water in photovoltaic performance and long-term stability. Reliable electrolyte additives and the modification of TiO2 diminishing the influences of water to the DSSC’s degradation process becomes a critical issue to maintain an acceptable cell life-time. The effects of water content on the degradation behavior of dye sensitized solar cells were studied by adding water isotopes (H2O, D2O, andH218O) to the electrolytes. Results showed that the degradation rates of the cells in presence of water isotopes were in the order of H2O > D2O > H218O. The improvement of the bis-benzimidazole derivatives c in the increase of photovoltage and the long-term stability resulted that the effective protection of the ligands between dye and working electrodes from the attack by environmental water molecules. The reduction of the degradation with Nitrogen doped TiO2 DSSC resulted that decreasing the resistance of the back reaction revealed a higher short circuit current (Jsc) and efficiency after 6 months. The efficiency of Nitrogen doped TiO2 for DSSC remained 25% compared with the 10% of pure TiO2 for DSSC after 6 months radiation. The results suggest the water adsorption capability of nitrogen-doped TiO2 is lower than that of TiO2. The combination of Nitrogen doped TiO2 and bis-benzimidazole derivative additive in DSSC will be crucial for further improvement in device’s open circuit voltage (Voc) and Jsc.

並列關鍵字

Degradation ； Long-term stability ； water effect ； Nitrogen doped TiO2 ； Dye sensitized solar cell

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