探討添加奈米碳管/聚乙醯胺混成材料於膠態電解質之交互作用與提昇染料敏化太陽能電池之性能

High Performance of Dye-Sensitized Solar Cells: MWCNTs Installed Gel Electrolytes

王映樵(Ying-Chiao Wang)

指導教授 ： 林江珍

共同指導教授 ： 何國川(Kuo-Chuan Ho)

國立臺灣大學/工學院/高分子科學與工程學研究所/碩士(2011年)

https://doi.org/10.6342/NTU.2011.01350

摘要

在染料敏化太陽能電池(DSSC)的研究中，聚偏二氟乙烯－共－三氯乙烯 (p(VDF-co-HFP)) 及其衍生物普遍使用於膠態電解質。因p(VDF-co-HFP) 中的氟原子擁有較小的離子半徑及高電負度，預期能提升半固態電解質的離子導電度；為改善高分子型膠態電解質的界面及導電度的性質，在高分子電解質中加入 無機材料可降低高分子的結晶性，增進離子導離度進而提升膠態 DSSCs 整體效率。本實驗中，利用聚偏二氟乙烯－共聚－三氟乙烯 (p(VDF-co-HFP))膠化電解質，並添加均勻分散的奈米碳管，以製備半固態染料敏化太陽能電池 (DSSC)。同時，設計合成具有醯胺(amide)與亞醯胺 (imide)官能基之高分子(poly(oxyethylene)-segmented amide and imide, POEM) 並應用於分散多壁奈米碳管(MWCNT) 。在標準光源100 mW cm-2的照射下，加入0.25 wt% MWCNT/POEM混成材料於半固態DSSC，可以得到短路電流密度 (JSC)與光電轉換效率 (η)分別為15.3 mA cm-2與6.86%。電化學交流阻抗儀(electrochemical impedance spectra, EIS)的分析中，0.25 wt% 混成膠態電解質亦可得到最低的Warburg阻抗 (Rw)。相較於未加入MWCNT/POEM於膠態電解質的半固態DSSC，其JSC與η分別為9.59 mA cm-2與4.63%。利用POEM分散MWCNT不僅增加p(VDF-co-HFP)之非結晶相並且具有螯合Li+離子的作用，進一步能促進I-離子的擴散能力，使得此半固態DSSC擁有相當高之光電轉換效率。

關鍵字

膠態電解質 ； 多壁奈米碳管 ； 聚亞醯胺 ； 半固態染料敏化太陽能電池

並列摘要

The gel electrolytes consisting of a well-dispersed carbon nanotubes and poly(vinyidene fluoride-co-hexafluoro propylene) p(VDF-co-HFP) were prepared for the quasi-solid-state dye-sensitized solar cells (DSSCs). A structurally tailored oligomers with functionalities of poly(oxyethylene)-segmented amides and imides (POEM) was synthesized and used for dispersing multi-walled carbon nanotubes (MWCNTs). When incorporated into the p(VDF-co-HFP)-based gel electrolytes, the performance of thte quasi-solid-state DSSC had been enhanced. At 100 mW cm-2 irradiation, the short-circuit current density (JSC) and power-conversion efficiency (η) of the DSSC containing 0.25 wt% MWCNT/POEM hybrids gel electrolyte were found to reach the best performance of 15.3 mA cm-2 and 6.86%, respectively. The lowest Warburg resistance (Rw) of this DSSC was characterized by the electrochemical impedance spectra (EIS) analyses and found to be consistent with the high performance. By comparison, the corresponding values of JSC = 9.59 mA cm-2 and η = 4.63% for a DSSC based on the pristine p(VDF-co-HFP) gel electrolyte were attained as the reference. The existence of the well-dispersed MWCNT by POEM not only increase the amorphous state of the p(VDF-co-HFP) but also promote the chelating behavior to the Li+. The system further facilitates the diffusion of ion pair, I-/I3- in the electrolytes and benefits to DSSC performance. The fine dispersion of MWCNT in the gel electrolyte is essential in this system and evidenced mainly by transmission electric microscope (TEM).

並列關鍵字

gel electrolyte ； multi-wall carbon nanotubes ； polyimide ； quasi-solid-state dye-sensitized solar cell

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