新穎主動層材料在倒置太陽能電池之載子傳輸層形貌改善

Improved Charge Transport Morphology of Inverted Structures Base on the Novel Active Layer Materials

藍翔(Shiang Lan)

指導教授 ： 林清富

國立臺灣大學/電機資訊學院/光電工程學研究所/碩士(2012年)

https://doi.org/10.6342/NTU.2012.10419

摘要

近年來高分子太陽能電池的進展快速，由於許多新穎的的有機太陽新材料問世，元件效率已經突破了10%的大關、另一項重要的指標則考驗元件是否能達到10年壽命，因此在本論文中研究以高穩定的倒置結構、並使用新穎主動層材料來組裝太陽能電池，在初步的組裝元件上遇到了一些問題、在本論文中會將這些問題一一進行改善。
首先在以施體P3HT-base系統為主的倒置結構中，改以新穎的IC60BA取代常用的PC60BM受體材料，來提升整體元件的開路電壓，但遇到了IC60BA相分離的問題，為了解決這個問題、我們提出了混摻高分子量的PVK，來改善巨觀的IC60BA:P3HT主動層均勻性，最後發現電洞高遷移率的PVK、除了能有效的改善巨觀的成膜機械性能，將開路電壓從 0.73V提升到0.82V、短路電流從6.30 mA/cm2提升到9.54 mA/cm2，最後整體元件效率從3.4%提升到4.5%。
第二部分中則以新穎的低能隙施體材料PCDTBT-base系統混摻PC70BM，來嘗試全溶液製程的倒置結構高分子太陽能電池、但是漏電流過大降低填充因子和短路電流，因此提出以蒸鍍高功函數的MoOx薄膜、來做為PCDTBT:PC70BM的電洞傳輸層，並在倒置結構的主動層內部形貌最佳化，最後發現PCDTBT:PC70BM、以CB/CF(1:3)的混合主溶劑下，能得到較好的施-受體的奈米交錯結構，元件電流從7.01 mA/cm2提升到9.76 mA/cm2，效率順利的從1.9%提升到4.5%。前面主要在論證了電洞傳輸層、在低能隙高分子上方之陽極修飾的重要性，接著本篇論文的最後部分將注意力擺在主動層下方的ZnO seed layer電子傳輸層，在此提出利用溶液製程水熱法、在ZnO seed layer上生長ZnO nanorods，主要目的是利用高比表面積(specific surface area)的ZnO nanorods，來陰極修飾以提昇載子收集能力，最後發現以75mM濃度生長的ZnO nanorods、並輔以氮氣退火，能夠大幅將短路電流從11.18 mA/cm2提升到15.11 mA/cm2，使得效率成功的從4.1%提升到5.5%。

關鍵字

高分子太陽能電池 ； 溶液製程 ； 倒置結構 ； 氧化鋅奈米柱、界面修飾

並列摘要

Polymer solar cell is progressed rapidly with a power conversion efficiency reaching 10% which will become commercial products soon. Another important indicator is the test of whether the component can reach 10 years of life time, to the high stability of the inverted structure, and use of novel active layer materials to fabricated solar cells, and have encountered some problems in the initial assembly of components on the research in this paperin this paper, these problems will be discussed and improved case by case in thesis.
In the first part of thesis, donor the P3HT-base system mainly inverted structure, changed to a novel IC60BA substituted a common PC60BM receptor material, to enhance the open-circuit voltage of the element as a whole, but encountered IC60BA phase separation, in order to resolve this problem, we propose a blend of high molecular weight PVK to improve macro IC60BA: of P3HT active layer uniformity. As the result, found that the hole mobility of PVK in addition to effectively improve the film formation of macroscopic mechanical properties. By the above improvements, the open voltage of device improved from 0.73V to 0.82V. The short-circuit current density enhanced from 6.30 mA/cm2to 9.54 mA/cm2 and the power conversion efficiency from 3.4% to 4.5%.
The second part at a novel low band gap donor material PCDTBT-base system blends PC70BM, to try the solution process inverted structure polymer solar cells, but the leakage current is too large to reduce the fill factor and short-circuit current, and therefore propose to evaporationhigh work function MoOx film, as the hole transport layer PCDTBT: PC70BM and the internal morphology of the active layer of the inverted structure optimization, and finally found PCDTBT: PC70BM, CB / CF (1:3) mixedmain solvent, can get better facilities - the nano staggered structure of the receptor. After all, the short-circuit current density enhanced from 7.01 mA/cm2 to 9.76 mA/cm2 and the power conversion efficiency from 1.9% to 4.5%. In front of the main argument in the hole transport layer, anode modified importance above the low band gap polymer, followed by the last part of the thesis focus on the active layer below the ZnO seed layer electron transport layer proposed use of thissolution process water heat method, ZnO seed layer on the growth of ZnO nanorods array main purpose is to take advantage of the high specific surface area of the of ZnO nanorods array, to cathodic modified to enhance the carrier collection ability, Finally found 75mM concentration growth of ZnO nanorods arrayand supplemented by nitrogen annealing. Finally, the short-circuit current density enhanced from 11.18 mA/cm2 to 15.11 mA/cm2 and the power conversion efficiency from 4.1% to 5.5%.

並列關鍵字

Polymer Solar Cells ； Solution Process ； Inverted Structure ； ZnO NRs ； Interfacial Modification

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