奈米結構材料之表面光電位研究

Investigations on Surface Photovoltage of Nanostructured Materials

陳衍方(Yan-Fang Chen)

指導教授 ： 吳忠幟

國立臺灣大學/電機資訊學院/電子工程學研究所/碩士(2011年)

https://doi.org/10.6342/NTU.2011.10883

摘要

表面光電位(surface photovoltage, SPV)現象是指材料受光照後產生電荷分離，材料的表面電位(surface potential)發生改變的現象。SPV可用於探究材料的吸收及電荷傳遞等基本性質。
此論文中，我們架設了三種表面光電位量測架構。利用這些架構，我們量測受雷射脈衝激發之SPV暫態訊號、穩定激發光源之SPV暫態訊號、以及表面光電位頻譜。藉由特別設計的樣品製備方式，我們在染料敏化二氧化鈦奈米孔隙結構上進行SPV量測，以探討染料敏化太陽能電池(dye-sensitized solar cell, DSSC)中產生電荷分離的過程。我們成功的在三個架構中量測到了SPV訊號。其中針對雷射脈衝激發之SPV暫態進行了一系列的實驗，以探究不同照光條件及周遭環境之影響。

關鍵字

表面光電位 ； 電荷分離 ； 染料敏化太陽能電池 ； 奈米結構 ； 暫態

並列摘要

Surface photovoltage (SPV) is the phenomenon that the surface potential of a material changes when the charges are separated due to illumination. The measurement of SPV can be used to investigate fundamental properties of materials, such as light absorption and charge transportation.
In this thesis, three SPV measurement configurations were set up to measure SPV transient signals after laser pulse excitation, SPV transient signals during continuous illumination, and the spectral response of SPV. Combined with designed sample configurations, these three systems were applied to study dye-sensitized titanium dioxide nanoporous structures, which play a basic role in charge separation in dye-sensitized solar cells (DSSCs). In particular, we conducted a series of experiments to investigate the effects of illumination conditions and ambient environments on SPV transient signals after laser pulse excitation.

並列關鍵字

surface photovoltage ； charge separation ； dye-sensitized solar cell ； nanostructure ； transient

參考文獻

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[4] Thomson, W, Contact theory of metals. Philosophical Magazine 1898, 46, 82.

[6] Goodman, A. M., Method for measurement of short minority carrier diffusion lengths in semiconductors. Journal of Applied Physics 1961, 32 (12), 2550