螢光散射層應用於二氧化鈦奈米管染料敏化太陽能電池之研究

Abstract

近年來綠色能源材料成為各方研究的主要目標，其中太陽能的技術與應用已然成為國際上永續能源的趨勢之一。在太陽能電池中，又以染料敏化太陽能電池具有製程簡易及良好可見光吸收等特性著稱。 染料敏化太陽能電池的光電轉換效率與染料所產生的電子效率十分有關，通過增加染料的光捕獲能力是有效增強光電轉換效率的方法之一。本研究利用螢光粉材料特有的吸收光譜及放射光譜之特性與N719染料產生螢光共振能量轉移效應(Förster resonance energy transfer effect, FRET)。將N719染料響應較低的波段轉換成響應較高的波段(400-600nm)。 本研究利用FRET效應，在電池的基礎結構上導入具有螢光特性的散射層，結果顯示，螢光散射層能提升染料敏化太陽能電池在380-530nm的量子轉換效率(IPCE)，並提高光電轉換效率。以40µm TiO2薄膜所製成染料敏化太陽能電池效率達到4.17%，其中開路電壓為0.66 (V)，電流通量為11.42 (mA/cm2)，填充值FF為0.55，與增添0wt%螢光散層相比提升幅度達28.3%。

Green energy materials become the main goal of research in recent years. The solar energy technology and application has become one of the international sustainable energy trends. Among the solar cells, dye-sensitized solar cells have characteristics of simple process and great absorption capacity of visible spectrum. The photon-to-electron conversion efficiency (PCE) of the dye-sensitized solar cells (DSSCs) strongly depends upon the electron generation efficiency from the dye molecules. One useful method in enhancing the PCE of DSSCs is to generate more electrons by enhancing the light harvesting of the dye molecules. The characteristic of the absorption and the emission spectrum of the phosphorescence material is used to produce Förster resonance energy transfer effect (FRET) with the N719 dye. The effect could convert less response spectrum into more response spectrum (400-600nm). This study would use the FRET to import a scattering layer with phosphorescence property to the structure of the cells. The results show that the phosphorescence scattering layer can improve the incident photon-to-electron conversion efficiency (IPCE) of the DSSCs at 380-530 nm and improve the PCE. The DSSCs made of 40μm TiO2 film and 7wt% phosphorescence scattering layer has an efficiency of 4.17%, of which Voc is 0.66V, Jsc is 11.42mA/cm2, and FF is 0.55, which is up to 28.3% compared with the DSSCs with 0wt% phosphorescence scattering layer.