利用退火以及外加電場提升有機-無機混掺奈米材料之電荷傳導研究

Study on charge transport properties of organic/inorganic nanomaterial by using annealing an electric field treatment

李秋茂(Chiu-Mou Li)

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(2008年)

https://doi.org/10.6342/NTU.2008.00105

摘要

中 文 摘 要
本研究主要為探討有機共軛高分子─無機半導體材料混摻構成之光伏元件的電性─導電度及其結構相關性質。
在本論文中首先探討接觸電阻與導電度的關係。再來是探討二氧化鈦奈米粒子混摻導電高分子P3HT的導電度，並分別在混摻不同二氧化鈦奈米粒子濃度、不同方向(平行與垂直基板方向)、與不同尺寸大小(nanorod與nanoparticle)的奈米粒子下導電度的變化。由實驗中可以發現，導電度會隨著混摻TiO2濃度的增加而昇高，這是因為隨著TiO2混摻濃度的昇高，逐漸形成較為連續的載子傳導路徑，所以導電度昇高。就不同尺寸大小的TiO2而言，在較低混摻濃度時，混摻TiO2 nanorod的導電度較高，這是因為在相同重點比例下，TiO2 nanorod的形狀較為狹長，因此較容易形成連續的載子通路，所以導電度較高。在混摻高濃度時，混摻TiO2 nanoparticle的導電度較高，這是因為在混摻高濃度時，因為TiO2 nanoparticle尺寸較小(5*10nm)，所以可以形成較密集的似網狀載子通路，所以導電度較高。
再來是探討經由溶劑退火處理(Solvent vapor treatment)、熱退火處理(Thermal anneal)與電場(Electric Field treatment)等物理方法來進一步使混摻層內的分子有足夠的動力與時間進行重組，以形成更為有序的結構排列，進而提高TiO2/P3HT作用層的載子傳輸。
最後使用吸收光譜圖與XRD繞射圖來證實混摻系統結構的變化，進而找出最佳的處理條件來增加載子的傳導。

關鍵字

二氧化鈦 ； 導電高分子 ； 混摻系統 ； 載子傳導 ； 後處理

並列摘要

Abstract
In this thesis, the charge transport and charge separation (photo response) of inorganic/organic hybrid conducting material were studied. P3HT and titania are frequently used as good electron donor and electron acceptor in inorganic/organic hybrid solar cell, because their good chemical stability, thermal stability and good charge transport properties.
In this study, we use titania dioxide nanomaterial hybrid conducting polymer (poly-(3-hexylthiophene), P3HT) to discuss conductivity in different concentrations , different directions(horizontal direction and vertical direction) and different inorganic material sizes.
With the increasing concentration of TiO2, TiO2 nanocrystals can form more conducting paths for charge transport. Also, the conductivity is enhanced with the increasing concentration of TiO2 .
The charge transport in TiO2 nanorod is better than TiO2 nanoparticle at low concentration; however, the charge transport in TiO2 nanoparticle is better at high concentration.
We also study the influence of the conductivity during different physical post treatment, such as solvent annealing treatment, thermal annealing treatment and electrical field treatment.
After post treatment, such as solvent annealing, thermal annealing, and electric field treatment, the conductivity increases because P3HT will be ordered and the mean size of ordered structure will enlarge.
Finally, we use XRD、absorption spectrum and TEM to prove the change of P3HT/TiO2 hybrid system structure and try to find out the optimized condition for charge transport.

並列關鍵字

Charge transport ； TiO2 ； P3HT ； Hybrid system ； Post treatment

參考文獻

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