本論文利用高游離能材料雙萘苯胺苯丁烯二腈(bis(4-(N- (1-naphthyl)phenylamino)phenyl)fumaronitrile, NPAFN)作為施體層來製作高開路電壓之有機太陽能元件，NPAFN的材料特性藉由紫外到可見光光譜儀、光電子光譜儀、原子力顯微鏡及空間電荷限制模型來檢測，結構為ITO/NPAFN/C60/4-Hydroxy-8-methyl-1,5-naphthyridine aluminium chelate (AlmND3)/Al之有機太陽能元件，經由光場及電性的調變，功率轉換效率達2.02%，元件接近1 V之高開路電壓，主要是歸因於NPAFN的最高佔據分子軌域(5.7 eV)及C60的最低未佔據分子軌域(4.2 eV)所產生的高能階差，光電轉換效率的結果顯示NPAFN所貢獻的光電流和C60所貢獻的光電流是等量的，因此可以說明NPAFN不止提供了高開路電壓，同時也讓元件擁有不錯的光電流。
而最佳化的元件，同時也利用變鍍率來更進一步研究NPAFN的鍍率對有機太陽能光伏效應之影響，由表面形貌可看出，不同鍍率下造成分子排列之間影響甚大。而透過等效電路模型的近似擬合及空間電荷限制電流的分析，可以發現在高鍍率下，因為NPAFN分子之間的作用力變弱，導致NPAFN的載子遷移率越低。同時，開路電壓會因分子作用力變低而提升，而元件的效率，在NPAFN鍍率0.5 nm/s下，可以達到2.3%。
有機太陽能元件同時也作電激發的檢測，在100 mA/cm2驅動電流下，可得元件的電流效率為0.11 cd/A，電激發頻譜顯示NPAFN為放光的來源，最後，因為含NPAFN/C60的元件在可見光的低反射率，因此該元件相較於傳統有機發光元件，有較高的對比度。

This thesis has demonstrated high open-circuit voltage (VOC) organic photovoltaic (OPV) device by introducing a high ionization energy material bis(4-(N-(1-naphthyl)phenylamino)phenyl)fumaronitrile (NPA- FN) as the donor layer. Characterization of NPAFN was thoroughly studied by the ultraviolet-visible (UV-vis) spectroscopy, photoelectron spectroscopy, atomic force microscopy (AFM), and the model of space-charge limited current (SCLC). Devices comprised ITO/NPAFN/ C60 / 4-Hydroxy-8-methyl-1,5-naphthyridine aluminium chelate (AlmND3)/Al were optimized to the power conversion efficiency (PCE) of 2.02% under AM 1.5G simulated solar illumination (1-sun) through the optical manipulation and electrical property tuning. The significant improvement in VOC of ~1 V was ascribed to the high energy difference between the highest occupied molecular orbital (HOMO) of NPAFN (5.7 eV) and the lowest unoccupied molecular orbital (LUMO) of C60 (4.2 eV). Incident photon-to-electron conversion efficient (IPCE) results reveal that the contribution of carriers from NPAFN competed with that from C60, which implied not only high VOC but also effective extraction of photocurrent for the function of NPAFN.
Device with such optimum structure was further analyzed in terms of the deposition of NPAFN. The performances under illumination and in the dark were studied. Morphological changes in different deposition rates indicated that the intermolecular interactions were considerably influenced during film deposition. The higher deposition rate of NPAFN resulted in the lower carrier mobility due to the weak molecular interaction, which was confirmed by the equivalent-circuit fitting and SCLC model. At the same time, the lower molecular interaction leaded to the higher VOC. Finally, the PCE was further improved to 2.3% at the NPAFN deposition rate of 0.5 nm/s.
The OPV device was also investigated into the electroluminescent (EL) properties. With the same OPV structure, the device exhibited current efficiency of 0.11 cd/A at 100 mA/cm2. The EL spectrum implied that the electron might recombine with the hole in the NPAFN layer. The practical application of light-emitting photovoltaic device was studied as the function of the device reflectance. Compared to the conventional organic light-emitting device (OLED), the device based on NPAFN/C60 possessed the higher contrast due to the relatively low reflectance within the visible spectrum.

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