- 學位論文
染料敏化太陽能電池教學實驗課程設計
The Experiment Course Design for Dye Sensitized Solar Cell (DSSC)
摘要
從19世紀發現照光產生了光電效應後，使用太陽這項取之不盡的能源作為發電的夢想就沒有停過。從早期的金屬無機太陽能電池到近年來第三代的太陽電池（有機可撓式、量子點電池…等）。目前看來，並沒有像前兩代的太陽能電池有著物理限制，因此研究人員在研究新一代的太陽能電池時，追求除了將光能轉換成電能的效率提高外，並希望藉著尋找可靠度高但便宜的材料來降低成本並擴展可及性，而敏料太陽能電池因為具有低成本、低製成難度及簡單的製程設備而因此具有高度的優勢。 自從1991 O’Regan與M.Gratzel發表了用N3-Dye製作了達7-8%的太陽能電池後，這20年間的歷程中，研究者們針對染料敏化太陽能電池中的正電極、對電極、電解液及染料等4個元件加以改良。由於染料敏化太陽能電池中各元件材料的選用、介面的匹配性相當複雜，往往一個元件的改變就可以造成電流、電壓乃至於效能的改變。這樣的複雜性也因此造就了數千種電池的組合，從不同的基板、電解質液與染料、製作電極的方式到不同的封裝技術，促成了各方的科學家不斷的嘗試各種組合來求得最佳的效能。 由於相關元件的搭配千變萬化，因此如何逐步拆解這複雜的變化，筆者建議採取由巨觀往微觀的觀點。先從電池模組效能量測的表徵現象了解整體電池運作的狀況，再逐步分解各元件並以微觀的角度觀察各元件改良方式及其影響，綜整歸納各項影響效率可能的因素。因此論文中的實驗設計上，也是依照上述的法則作為原則，先藉由巨觀的效能量測，了解各項表示太陽能效能的參數。例如FF、Isc、Voc等等，透過參數定義進一步衍伸出那些元件對於這些性質表徵的影響，接著介紹各元件的變數與造成變數的成因。舉例來說，染料敏化太陽能電池中最重要的元件莫過於染料，但染料的影響因素很多，例如不同的結構的染料，釕金屬(Ruthenium)為主的金屬錯合物染料、紫質(Porphyrins)與酞菁素(Phthalocyanines)的染料與有機染料，各類皆有不同的優缺點。舉紫質與酞菁素的染料為例，在設計上又利用不同的官能基或採用有機染料一樣的D-π-A結構，對於降低這類染料團聚現象，提升效能上面的差異性。在論文中，將針對不同結構的染料與相同結構但不同觀能基的染料設計兩組實驗，來了解染料對於太陽能電池效能的差異及可能造成此差異的原因。 過去兩年筆者對於學習染料敏化太陽能電池的過程中，深感其複雜度與困難度。從電池元件搭配的複雜度、各元件之間的介面、背景知識的複雜，橫跨了半導體、電化學、表面化學…等。因此想藉由此論文以及目前已了解的因素，設計一系列橫跨理論與實作的實驗，提供後續欲學習製作敏料染化太陽能電池之研究人員基礎知識的建立。並期許這一系列的實驗可作為未來敏料染化太陽能電池課程的老師們在設計實驗時的範例並納入太陽能光電學程中的課程之一。
並列摘要
Since photoelectric effect had been discovered in 19 century, the dream of using inexhaustible sun light as power generator had not been stopped. Scientists has improved the early stage inorganic metal solar cell to 3rd generation solar cell, such as organic flexible solar cell、quantum dot etc. So far, the 3rd generation solar cell seems no physical barrier like first two generation solar cell. Therefore, researchers in investigation of newer generation solar cell not only pursue the higher transfer efficiency in electricity, but also seeking more stability and economical material to reduce cost and expand popularity. Dye sensitized solar cell gains competitive advantages because of low cost、accessible manufacture processes and affordable equipment. After 1991 O’Regan and M.Gratzel published a solar cell with N3-dye reached 7-8% efficiency, in the past two decades, researchers had adjusted four major components, positive electrode、back electrode、electrolyte and dye in dye sensitized solar cell (DSSC). Due to different material selection and interface compatibility in DSSC is complicated, the change of one component and/or parameters would lead to the variation of photo current、voltage as well as solar cell efficiency. This kind of complexities results in thousands combination of batteries from different subtracts、electrolyte、dyes、fabrication method of working electrode to sealing skills, and it fascinate different field of scientists attempting different conjugation for better performance. Because of the various collocations, how to disassemble this complexity, I suggest choose from top down perspective. Starting from the measurement of cell efficiency to comprehend overall operation process, then tearing down into separated component to show how meliorated method to enhance performance, at the end , we sum up any possible factors. As a result, the experiment designation of this article follows principles mentioned above. At the beginning, we teach students how to measure the efficiency of solar cell, and understand parameter, such as FF, Isc, Voc ...etc. Through the definition of these parameters to reveal what the parameter is influenced by the variation of different components. For instance, one of the most important unit in dye sensitized solar cell is dye, but there are several factors could affect it. For example, different structure, complex metal dye with ruthenium in core、 dye with porphyrins and phthalocyanines or oraninc dye, they have different pros and cons. Take porphyrins and phthalocyanines as an instance, they may adopt D-π-A structure like organic dye and design different functional groups, not only lower the aggregation of sensitizer, but enhance the efficiency. In this thesis, we will sketch up a groups of experiment to show how different component may change and effect the efficiency. In the past two years learning journey in DSSC, I deeply endure its complexities and difficulties. In designation of DSSC, it is not only a challenge to consider compatibility of different components、complicated interface ,but also different background knowledge from semi-conductor、electrochemistry、surface chemistry …etc. In this thesis, I try to design a series of experiments across theory and practice based on factors influenced efficiency, and providing future researchers establish fundamental fabrication skills and background knowledge. I anticipate this series of experiments could be examples in the set-up of DSSC experimental courses.