Abstract In this paper, the efficacy of wild natural dyes as the sensitizer was investigated for the fabrication of natural dye-sensitized solar cells (DSSCs). The natural pigments were extracted from Crocus sativus (Saffron), Allium cepa L (red onion), Malva sylvestris (Mallow), and Oregano (Origanum vulgare) using solvent extraction method. Based on the UV–vis results, the extracted solutions have been shown to contain anthocyanin or chlorophylls pigments, which are excellent pigments required for the charge-carriers generation in the energy harvesting process from the sunlight. The efficacy of all sensitizers has been evaluated using the cyclic voltammetry and current-voltage open circuit experiments of the fabricated DSSCs. The photovoltaic performance of DSSCs in terms of efficiency, current, voltage, and filling factors was performed under standard illumination of AM 1.5G having an irradiance of 100 m W c m − 2 . The results showed that the photoelectric conversion efficiency of the fabricated DSSCs were nearly less than 2%, while the open-circuit voltage and short-circuit current density were from 0.43 to 0.55 V and 0.45–0.54 mAcm-2, respectively. The appropriate LUMO energy level and the band-gap of these extracted dyes would enable them to become efficient sensitizer for utilizing in fabricated DSSCs. Therefore, due to the existence of carbonyl and hydroxyl groups in dye's chemical structures, it enable them to bind to the T i O 2 layer, consequently, improve the electron transfer, and enhance the energy conversion efficiency of the fabricated DSSC.

中文翻译：

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天然天然染料作为染料敏化太阳能电池光敏剂的性能评价

摘要 本文研究了野生天然染料作为敏化剂在制备天然染料敏化太阳能电池（DSSCs）中的功效。使用溶剂提取法从番红花（藏红花）、洋葱（红洋葱）、锦葵（锦葵）和牛至（牛至）中提取天然色素。根据 UV-vis 结果，提取的溶液已显示含有花青素或叶绿素色素，这些色素是在从阳光中收集能量的过程中产生电荷载流子所需的极好色素。已使用制造的 DSSC 的循环伏安法和电流-电压开路实验评估了所有敏化剂的功效。DSSCs 在效率、电流、电压、和填充因子在具有 100 m W cm - 2 辐照度的 AM 1.5G 标准照明下进行。结果表明，所制备的DSSCs的光电转换效率接近2%，而开路电压和短路电流密度分别为0.43~0.55 V和0.45~0.54 mAcm-2。适当的 LUMO 能级和这些提取染料的带隙将使它们成为用于制造的 DSSC 的有效敏化剂。因此，由于染料化学结构中羰基和羟基的存在，使它们能够与TiO 2 层结合，从而改善电子转移，提高制备的DSSC的能量转换效率。结果表明，所制备的DSSCs的光电转换效率接近2%，而开路电压和短路电流密度分别为0.43~0.55 V和0.45~0.54 mAcm-2。适当的 LUMO 能级和这些提取染料的带隙将使它们成为用于制造 DSSC 的有效敏化剂。因此，由于染料化学结构中羰基和羟基的存在，使它们能够与TiO 2 层结合，从而改善电子转移，提高制备的DSSC的能量转换效率。结果表明，所制备的DSSCs的光电转换效率接近2%，而开路电压和短路电流密度分别为0.43~0.55 V和0.45~0.54 mAcm-2。适当的 LUMO 能级和这些提取染料的带隙将使它们成为用于制造 DSSC 的有效敏化剂。因此，由于染料化学结构中羰基和羟基的存在，使它们能够与TiO 2 层结合，从而改善电子转移，提高制备的DSSC的能量转换效率。分别为 54 mAcm-2。适当的 LUMO 能级和这些提取染料的带隙将使它们成为用于制造 DSSC 的有效敏化剂。因此，由于染料化学结构中羰基和羟基的存在，使它们能够与TiO 2 层结合，从而改善电子转移，提高制备的DSSC的能量转换效率。分别为 54 mAcm-2。适当的 LUMO 能级和这些提取染料的带隙将使它们成为用于制造 DSSC 的有效敏化剂。因此，由于染料化学结构中羰基和羟基的存在，使它们能够与TiO 2 层结合，从而改善电子转移，提高制备的DSSC的能量转换效率。