可交聯性共軛導電高分子材料開發合成與其有機太陽能電池運用

Abstract

摘要 本論文以thiophene為主體結構，設計開發合成新型共軛導電高分子供有機太陽能電池應用。利用GRIM method、metal-catalyzed cross coupling 與 SN2取代反應成功合成出可交聯性新型共軛導電高分子材料。新型可交聯性共軛導電高分子材料在光酸的作用下可進行開環交聯反應，交聯反應後可有效將此新型可交聯性共軛導電高分子材料(Donor)與PCBM(Acceptor)摻合物形態(morphology)做良好的控制。 研究中，以NMR、GPC、FT-IR、UV、AFM等儀器對新型可交聯性共軛導電高分子材料進行一系列物化性探討與驗證，由NMR對每一步驟合成成品作結構驗證與鑑定，藉由GPC分析得知，新型可交聯性共軛導電高分子材料分子量分佈大約在10000~19000 g/mol且擁有窄的分子量分佈，再經由FT-IR分析證明在光酸作用下可使新型可交聯性導電分子材料產生開環交聯反應。在UV-vis驗證下可得知光酸使用量及加熱烘烤時間對交聯程度很大影響。AFM掃描之下顯示新型可交聯性共軛導電高分子材料(Donor)與PCBM(Acceptor)混摻後未有相分離。 將此新型可交聯性共軛導電高分子材料應用在有機太陽能電池元件上，雖未有良好的效率表現，但在光酸洗去與再次以高溫加熱烘烤實驗中證明效率會獲得改善。在未來只要尋找出最佳alkyl Group與Oxetane Group比例、更好的清洗溶劑與更好封裝膠材，此類新型可交聯性共軛導電高分子材料在元件的效率、穩定度與life time應該會有不錯的表現。

Abstract In this thesis, thiophene was used as a main molecular architecture to develop and synthesize a new type of crosslinkable conjugated conducting polymer for organic solar cell application. This new type crosslinkable conjugated conducting polymer has been synthesized successfully by Grignard method through metal-catalyzed cross coupling and SN2 substitution reactions. Ring opening reaction can proceed under the mixing of photo acid and crosslinkable conjugated conducting polymer to form the crosslinked conducting polymer. This crosslinked polymer can properly control the morphology of the blend of this conducting polymer material (donor) with PCBM(acceptor). In this study, a series of identifications were carried out via NMR、GPC、FT-IR、UV and AFM. Synthesized products from each step were characterized by NMR analyses. The molecular weight was measured by GPC giving around 10000~19000 g/mol and a narrow molecular weight distribution. FT-IR was employed to monitor the ring opening reaction to demonstrate its crosslinkable reaction. UV-visible results showed that the amount of photo and annealing time have a great influence on the degree of crosslinking. AFM results indicated no phase separation for the blend of this crosslinked conjugated conducting polymer and PCBM. Although the practical application of this obtained crosslinkable conjugated conducting polymer on the organic solar cell did not achieved the desired efficiency, however, the experimental results indicated that the efficiency can be improved further through the removal of the photo acid by the washing process and the newly high temperature heating of the devices before packaging. In the future, if the optimal ratio of alkyl group to oxetane group can be determined, washing solvent and packaging adhesive can be further improved, this crosslinkable conjugated conducting polymer may possess good performance for future application in terms of device efficiency, stability and life time.