新穎紫質與有機染料共敏化設計於染料敏化太陽能電池上的應用

Abstract

在本論文中，我們呈現與暨南大學林敬堯教授實驗室、清華大學陳建添教授實驗室以及中研院洪政雄教授實驗室共同合作之成果。首先我們研究紫質染料中心取代成硼與無金屬中心的紫質，其結構對於染料敏化太陽電池光電轉換效率之影響。以洪教授實驗室所合成之硼系列染料為例，我們的研究結果顯示，修飾在硼上的烷氧長鏈取代基後可以有效地減緩電子攔截的逆反應，使元件的光電轉換效率提升。在第二個主題中，我們以染料共敏化的方式，將多種吸光範圍不同的染料共吸附到二氧化鈦上，使元件具備全光譜吸收的能力。以林教授實驗室所合成之LD系列之染料為例，其中LD14/H2LD14/An共敏化系統之最佳化元件效率可達9.7 %，由元件動力學的分析發現，An有機染料有助於防止紫質染料之間堆疊，減少電荷再結合的發生，而使開路電壓和短路電流都提升。在第三個主題中，我們研究鈷電解液在有機染料上的應用。以陳教授實驗室所合成之有機染料為例，其研究結果顯示具有立體障礙較大或是有烷氧基長碳鏈的有機染料，可有效減緩電子攔截的逆反應而增進其元件效率。

In this thesis, we present three parts of photovoltaic results for various porphyrins and organic dyes as potential sensitizers for dye-sensitized solar cells (DSSC). For the first part, we found that the boron center bearing long alkoxyl chains have an effect to protect the porphyrin core for a retarded charge recombination. For the second part, we present a rational design of co- sensitization using three dyes (LD14, H2LD14 and An), for which the co-sensitized dyes have complementary adsorption spectra, to improve the device performance for porphyrin-sensitized solar cells. Upon optimization, the device made of LD14+H2LD14+An yielded ƞ = 9.72%. We found that An plays a key role to retard charge recombination based on the results obtained from intensity-modulated photovoltage spectral measurement. For the third part, we investigated the photovoltaic performance of organic dyes in cobalt electrolyte. We found that the organic dyes bearing bulk groups and alkoxyl chains had the effect to reduce charge recombination so as to improve the device performance.