高分子及其蒙脫石奈米複合材料在膠態光敏型太陽能電池上的應用

Abstract

本研究的目的主要是探討膠態電解質系統(Polymer/ACN/LiI/ I2/TBP) 對於染料敏化二氧化鈦太陽能電池效能的影響。藉由使用不同的高分子與高分子–蒙脫石複合材料之膠態電解質系統，來尋找能夠維持液態元件的高光電轉化效率，且能改善液態元件的封裝問題之最適合材料。 經由量測膠態電解質的導電度，以及對膠態系統元件作交流阻抗分析，可得知離子在電解質中的導電效果以及元件中的阻抗分布。測量的結果為PMA電解質系統 (PMA/ ACN/ LiI/ I2/ TBP) 有較高的導電度與較好的離子擴散速率，而PNIPAAm電解質系統 (PNIPAAm/ ACN/ LiI/ I2/ TBP )的導電度最差，離子擴散速率也不佳。但加了蒙脫石之後，PMA電解質系統的導電度及離子擴散速率皆下降，但PNIPAAm電解質系統卻上升了不少。而對於PVAc電解質系統 (PVAc/ ACN/ LiI/ I2/ TBP) 而言，加了蒙脫石之後導電度及離子擴散速率並無明顯的變動。 以元件的表現來看，液態乙腈電解質系統在入射光能量為100mW/cm2的光電轉換效率可達8.69%，電流值也可高達5.27mA。而膠態電解質系統中，以PMA電解質系統的表現最好，有高達7.17%的光電轉換效率。而PVAc與PNIPAAm系統則分別為5.62%與3.17%。加了蒙脫石的三個系統中，光電表現非常接近。PMA電解質系統的各項數據皆有些許的下降，但還是有5.84%的高效率。而PNIPAAm電解質系統在加了蒙脫石之後，效率大幅提升原來效率的70%。而PVAc電解質系統在加了蒙脫石之後，各項數據只有些微的下降，前後差異並不大，分別為5.62%與5.12%。

The objective of the research is to study the effects of the gel-type electrolyte systems (polymer/ACN/LiI/I2/ TBP) on the performance of dye-sensitized titanium oxide solar cells. By using different polymer and polymer-MMT nanocomposite electrolyte systems, we intended to find suitable materials for high performance and good sealing properties of the solar cell devices. The performance of electrolyte for gel-type devices could be estimated by measuring conductivity and using EIS (Electrochemical Impedance Spectroscopy). The results was that the PMA electrolyte system (PMA/ACN/ LiI/I2/TBP) had higher conductivity and ionic diffusion rate. The PNIPAAm electrolyte system (PNIPAAm/ACN/LiI/ I2/TBP) had lowest conductivity and ionic diffusion rate. Addition of the montmorillonite (MMT) to gel-type electrolyte system, the conductivity and ionic diffusion rate of the PMA electrolyte system decreased, but the PNIPAAm electrolyte system increased. For the PVAc (PVAc/ACN/LiI/ I2/TBP) electrolyte system, the conductivity and ionic diffusion rate were not siginificantly changed with the addition of the MMT to the system. For the performance of the devices, the photon-to-electron power conversion efficiency of liquid ACN electrolyte system (ACN/LiI/I2/TBP) was 8.69% and the current was 5.27mA at an incident light intensity of 100mW/cm2. For gel-type electrolyte system, the PMA electrolyte system had best performance and its efficiency could reach as 7.17%. The efficiencies of PVAc and PNIPAAm system were 5.62% and 3.17%, respectively. For three systems with the MMT, the performances were very close. Although the data of PMA electrolyte system decreased after adding the MMT to the system, it still had high efficiency as 5.84%. The efficiency of the PNIPAAm system increased 70% after adding the MMT to the system. The PVAc and PVAc+MMT electrolyte systems with the efficiencies of 5.62% and 5.12%, respectively, were almost the same.