濕式製程製備氧化釩/石墨烯氧化物－複合介面修飾層並製作具有高穩定性及高效能之反式有機太陽能電池與其在電子元件上的應用

Abstract

本研究的第一個部分是以溶劑溶膠法自氧化釩前驅物三異丙醇氧化釩(V)(Vanadium triisopropoxy oxide)中製備過渡金屬氧化物之氧化釩(V2O5)，並此方法製備透明導電薄膜並量測其穿透度以及導電度，得到其性質。同時也以改良之Hummer Method製備具有二維奈米平面結構石墨烯氧化物。隨後以拉曼光譜以及紅外光光譜鑑定其結構。而第二個部分則為將製備完成的氧化釩以及石墨烯氧化物以旋轉塗布之濕式製程的方式，製備為陽極修飾層並應用於有機太陽能電池之中。在成功的應用在傳統太陽能電池元件結構之後，更成功的將此結構應用於具有高度穩定性以及高效率反式結構之中，使製備出的元件可在1000小時的保存下仍可有八成以上的元件效率。而搭配低能隙材料PBBCPDT-FBT更是能將元件效率提升至6.2 %。除了有機太陽能電池元件的製作之外，在本研究中更是發現此陽極修飾層亦可應用於高分子有機發光二極體之中。證明了此結構是具有相當優異的特性的。研究的第三個部分則為利用元件的暗電流分析、電洞遷移率、薄膜型態分析、化學分析影像能譜儀以及光激發光譜來探討此一複合陽極修飾層的特性。並驗證此一結構具有相當好的電洞傳遞特性以及可以有效的阻絕前驅物向下滲透進入有機材料中的問題。此研究結果也為將來發展過渡金屬氧化物作為介面修飾層的研究，提供了一個新的方法改善元件的效率以及穩定性。

In this study, we prepare a new V2O5/GO composite layer that can be used as an interfacial layer between Ag and active layer by solution process. V2O5 film was prepared by sol-gel process, and its properties, transmittance and resistivity, were characterized in this research. Graphene Oxide(GO) was synthesized by modified Hummer method, and we characterized the GO thin film by Raman and FT-IR spectroscopy. This composite interfacial layer was used to fabricate conventional and inverted polymer solar cell. Both P3HT:PCBM and PBBCPDT-FBT:PCBM system were used for the bulk heterojunction layers. For the P3HT:PCBM system, the power conversion efficiency of ITO OPV device can be enhance from 3.6 % to 4.1 %. Simultaneously, the power conversion efficiency of the PBBCPDT-FBT:PCBM systems can also be enhanced from 2.2 % to 6.2 %. The device with this composite interfacial layer showed its better performance and stability. After 1000 hours storage, this device still remain 80 % performance. Finally, we analyzed the thin film property with atomic force microscopy (AFM) , photo luminance spetra(PL), and electron spectroscopy for chemical analysis system(ESCA). Dark current and hole mobility were also measured in this study. The experiment results show that the composite interfacial layer can inhibit the diffusion of the vanadium and enhance the hole transport in the device.