有機無機混摻薄膜太陽能電池之光電特性研究

Hybrid P3HT/TiO2 Nanorods Bulk Heterojunction Solar Cells

黃則凱(Tse-Kai Huang)

指導教授 ： 陳俊維

國立臺灣大學/工學院/材料科學與工程學研究所/碩士(2007年)

https://doi.org/10.6342/NTU.2007.01396

摘要

本研究主要為有機共軛高分子-無機半導體材料混摻形成之光伏元件的光電性質探討。首先，探討純的導電高分子材料在製作光伏元件為何會失敗。然後探討混摻TiO2奈米顆粒後，由於奈米材料有獨特的表面物理現象，因此可以幫助載子分離，另外也可以提供有效的傳導路徑，最後可以達到效率大幅的提高。

其次，我們觀察熱處理對元件所產生的影響，發現在高溫下退火可以有效的提高效率。因此從光學、XRD、載子飛行時間(Time-of-Flight)等實驗來觀察熱處理對元件所產生的影響。

最終利用合成方式的改變，製作出不同尺寸的TiO2奈米顆粒，來探討不同混摻物尺寸對元件效率的貢獻。奈米顆粒的主要貢獻可以分成兩部分，載子分離(Charge separation)和載子傳導(Charge transport)，而在相同的TiO2混摻濃度下，較短的TiO2擁有較多的表面積因此可以貢獻較有效率的載子分離，而長的TiO2卻可以容易形成比較連續的傳導路徑，因此在這兩種效應的平衡下，試圖找出元件效率的最大值。

關鍵字

二氧化鈦 ； 有機太陽能電池

並列摘要

The investigations focus on hybrid materials photovoltaic properties of organic conjugated polymer and inorganic nano-semiconductor. First of all, we discuss how TiO2 nanorods support charge separation and charge transport in TiO2/P3HT hybrid solar cells. Therefore we tune the TiO2 doping concentration to optimize devices performance.

Secondly, we focus on the topic of thermal treatment effect on devices performance. It is observed that devices performance could significantly enhance after high temperature annealing. Based on optical properties, XRD, and Time-of-Flight carrier mobility measurement system, we discover that after annealing both the crystallite size and carrier mobility increasing.

Finally, we use synthesis method to change the length of TiO2 nanorods and investigate the length dependent effect on devices performance. We know that TiO2 inclusion supports both charge separation and transport, therefore we focus on different length of TiO2 nanorods effect on charge separation and transport properties. At the same doping concentration, the shorter TiO2 nanorods result in more surface area and contribute to more efficient charge separation; the otherwise the longer TiO2 nanorods could easily form continuous transport path to support efficient charge transport. Based on the balance of these two effects, we try to find the maximal performance of TiO2/P3HT hybrid solar cells.

並列關鍵字

TiO2 ； P3HT ； solar cell

參考文獻

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