PDF(Pubmed)
Abstract：
Environmental sustainability, resource availability, and cost-effectiveness are the driving forces behind the search for natural sensitised dyes to replace synthetic ones. Using a combination of pigments as the sensitised dye in dye-sensitised solar cells (DSSCs) offers several advantages over using a single pigment. In this present study, natural dyes with different pigments were extracted from three local plants: Coccinia grandis (Ivy gourd leaves, IGL), Oryza sativa Linn (Black glutinous rice, BGR), and Curcuma longa L. (Turmeric, TM). Each colour extract absorbed various wavelengths of light. It was found that the single IGL-dye (green) had a greater light absorption and energy band gap over visible light than other extracts (dyes). Then combinations of these dyes were examined. A sensitised dye combination with a primary to secondary dye in a volumetric ratio of 80/20 exhibited multiple energy band gaps, implying multiple electron excitations at different photon energy levels. Compared to other mixed dyes, IGL/TM-dye had the highest absorbance and electron excitation at three wavelengths with the smallest energy band gap values of 1.74, 2.51, and 2.59 eV. The IGL-dye had the highest DSSC efficiency of 0.15 % for single dyes, followed by the TM-dye and BGR-dye, which had 0.12 % and 0.04 %, respectively. Interestingly, for combined dyes, the IGL/TM dye increased DSSC efficiency to 0.3 %. Since natural dyes tend to be less effective in DSSCs than synthetic dyes because they have a narrower absorption range, higher redox potentials, shorter operational lifetimes, higher rates of electron recombination, and different molecular structures, the dye co-sensitization strategy is one of the best ways to make more effective cells in the future.
摘要：
环境可持续性,资源可用性，和成本效益是寻找天然敏化染料取代合成染料的驱动力。在染料敏化太阳能电池(DSSC)中使用颜料的组合作为敏化染料提供了优于使用单一颜料的若干优点。在本研究中,从三种当地植物中提取了具有不同色素的天然染料：Cocciniagrandis（常春藤葫芦叶，IGL),水稻（黑糯米，BGR),和姜黄(姜黄，TM）。每种颜色提取吸收各种波长的光。发现单一IGL-染料(绿色)具有比其它提取物(染料)更大的光吸收和超过可见光的能带隙。然后检查这些染料的组合。敏化染料与初级染料和次级染料的体积比为80/20的组合表现出多个能带隙，意味着在不同的光子能级下的多个电子激发。与其他混合染料相比，IGL/TM染料在三个波长下具有最高的吸光度和电子激发，最小的能带带隙值为1.74、2.51和2.59eV。IGL染料对单一染料的最高DSSC效率为0.15％，其次是TM染料和BGR染料，分别为0.12%和0.04%，分别。有趣的是,对于组合染料，IGL/TM染料将DSSC效率提高到0.3%。由于天然染料在DSSC中的效果往往不如合成染料，因为它们具有较窄的吸收范围，更高的氧化还原电位，更短的操作寿命，更高的电子复合率，和不同的分子结构，染料共敏化策略是未来制造更有效细胞的最佳方法之一。
