石墨烯材料應用於透明有機太陽能電池的特性分析

The Investigation of Semi-Transparent Graphene Organic Solar Cells

陶玠伊(Jieh-I Taur)

指導教授 ： 吳志毅

國立臺灣大學/電機資訊學院/光電工程學研究所/碩士(2014年)

https://doi.org/10.6342/NTU.2014.02904

摘要

本篇論文討論以石墨烯材料當作本體異質接面有機太陽能電池電極的製備方式與成果表現。使用石墨烯做為電極，可達到透明、製程時間縮短與全溼式製程等優點。
首先，運用無高分子聚合物轉印方法製備單層與多層石墨烯並量測特性。再者，比較參雜濃度對於功函數、導電性與穿透度等性質影響。利用石墨烯電極取代銀電極做為有機倒置太陽能電的陽極，進而令元件達到透明。調變石墨烯的層數、參雜濃度與主動層轉速等，尋求最佳化的參數。經過調變各個參數之後，當主動層轉速為 600 rpm 三層石墨烯參雜 PEDOT:PSS 的條件，在 P3HT:PC 61 BM 系統下可達到 2.82 %的能量轉換效率，使用吸光頻譜較廣短路電流密度較高的材料PBDTTT-C-T:PC 71 BM 下則能達到 4.20 %。
最後，我們嘗試將電洞傳輸層由蒸鍍的三氧化鉬改為旋轉塗佈製程PEDOT:PSS，藉此讓元件成為全溼式製程。我們調變 PEDOT:PSS 的塗佈條件使其最佳化，當 UV/Ozone 時間 30 s PEDOT:PSS 轉速 4000 rpm 下，可達到在P3HT:PC 61 BM 系統 1.71 %的能量轉換效率，我們將同樣的製程條件應用在擁有較高開路電壓的材料 P3HT:ICBA 中，可以達到 2.59 %的轉換效率。

關鍵字

有機太陽能電池 ； 石墨烯 ； 透明太陽能電池 ； 溼式製程 ； 轉印

並列摘要

In this thesis we study about the performance of bulk heterojunction inverted organic solar cells using graphene material as electrodes. Using graphene to replace silver as anodes could achieve the goals of transparent devices, reducing the fabrication time and all-solution processes.
We used the polymer-free method to transfer graphene from Cu foil to other substrates. We produced single- and multi-layer graphene along with measuring their characteristics. We investigated the influence of doping concentration on work function, sheet resistance and transmittance. After measuring the graphene characteristics in different conditions, we incorporated it in inverted organic solar cells to make the transparent devices. Optimizing the number of graphene layers, doping concentration and active layer spin rate, we could achieve PCE 2.82% in P3HT:PC 61 BM system and 4.20% in PBDTTT-C-T:PC 71 BM system, which has wider light absorption ranges and can produce higher short circuit current.
Finally, we replaced vacuum-evaporated MoO 3 with PEDOT:PSS formed by spin coating to enable our fabrication process became all-solution without any vacuum processes. Optimizing the process parameters of PEDOT:PSS films, we found that 30 s UV/Ozone radiation and 4000 rpm spin rate can give best result. Using this process, we can get PCE 1.71 % in P3HT:PC 61 BM based devices. By replacing PC 61 BM with ICBA, which can give us higher open circuit voltage, we could reach PCE 2.59%.

並列關鍵字

organic solar cell ； graphene ； transparent solar cell ； all-solution fabrication ； transfer

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