電子阻擋層運用於高分子太陽能電池之研究

Study of electron blocking layer in polymer solar cells

陳柏諭(Po-Yu Chen)

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(2009年)

https://doi.org/10.6342/NTU.2009.10487

摘要

最近幾年來，有機高分子材料製作成的太陽能電池受到了許多的關注，主要是因為其有製程便宜、且具有可撓性、製程低溫、輕薄且可大面積的製作等許多的優點，也因此吸引了許多相關的研究專注於此，而要如何更進一步的提升有機高分子太陽能電池的效率也成為大家探討的首要目標，而目前主要能夠提升效率的方法有延長結晶時間、熱處理、在有機層作摻雜或在導電層摻雜，或是是採用一些更有效率的結構，而目前最受到矚目的就是P3HT/PCBM這種donor-acceptor的異質混成結構，許多文獻與實驗都指出這種異質混合結構能夠更有效率的分離電子電洞對，隨著技術的成熟目前已經能夠更有效率的產生電子電洞對，但這裡就出現了ㄧ些問題，雖然產生電子電洞對的效率增加了許多，但若是分離的電子電洞對恰好在陽極的附近，就會使得一些原本該流向陰極的電子流到陽極去，形成所謂的漏電流，漏電流流入陽極內，會與在陽極複合，造成元件的操作電壓下降，進而使得並聯電阻及開路電壓的下降，因此我們希望藉由在有機吸光層與電極之間加入一層電子阻擋層，利用此電子阻擋層的能階障礙來阻擋電子往錯的方向移動，我們分別在傳統結構以及反向結構使用電子阻擋層，此電子阻擋層也成功的使得元件在開路電壓、並聯電阻、以及填充因子有所提升，也使得元件的整體效率提升了。

關鍵字

電子阻擋層 ； 本體異質結構 ； 高分子太陽能電池

並列摘要

In recent years, organic photovoltaic (OPV) cells offer several advantages over the more traditional inorganic photovoltaic cells, including fabrication with flexible substrates, light-weight, production by low-cost techniques such as spin-coating and printing, large area and low temperature. Thus, the BHJ structure has emerged as an attractive OPV architecture because the phase-separated active layer promotes efficient separation of photogenerated excitons into charge carriers. But there is always a problem in BHJ cells that both the donor polymer and the acceptor molecule are touching both electrodes. This means that electrons in the PCBM may be formed at an interface very close to the ITO anode, which typically collects the holes. Any electrons transferred to the ITO would essentially recombine with holes and reduce the working voltage and the power conversion of the device. A similar effect should take place at the cathode if the device was reversed.
We use an electron blocking layer between the active layer and the anode to prevent the leakage current. Result show that the prevention of leakage current leads to the greater performance of shunt resistance and open circuit voltage. The EBL is beneficial to the prevention of leakage current, resulting in higher performance of the photovoltaic cell.

並列關鍵字

electron blocking layer ； bulk heterojunction structure ； polymer solar cells

參考文獻

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