%0 Journal Article
%T <br>
%A 赵金鸽
%A 郝学良
%A 韩亮
%A 高建荣
%J 物理化学学报
%D 2015
%R 10.3866/PKU.WHXB201509075
%X 选择N-正丁基咔唑作为电子给体,芴酮作为桥键,苯甲酸作为受体,通过桥键芴酮与给体和受体连接位置的改变,设计合成了两个咔唑染料4-(6-(N-正丁基咔唑-3-基)-9-氧-9H-芴-3-基)苯甲酸(HXL-3W)和4-(7-(N-正丁基咔唑-3-基)-9-氧-9H-芴-2-基)苯甲酸(HXL-4Z).对咔唑染料的光谱性能、电化学性能和光电转换性能进行了研究,并运用密度泛函理论(DFT)方法对其几何结构和紫外-可见光谱进行了优化计算.结果表明, HXL-4Z的吸收光谱呈现两个明显的π→π*跃迁吸收峰和一个较小的对应于分子内电荷转移的吸收峰,而HXL-3W的吸收光谱则仅呈现一个π→π*跃迁吸收峰,且摩尔吸光系数远小于HXL-4Z.可能是HXL-3W分子结构中给体和受体距离较近,张力较大,导致较差的分子平面性和分子内电荷转移.因而HXL-4Z的光吸收能力和电子注入效率较优,从而具有较好的光电转换效率(2.03%) (短路电流(JSC) = 3.88 mA·cm-2,开路电压(VOC) = 700 mV,填充因子(FF) = 0.75).<br>4-(6-(N-butylcarbazole-3-yl)-9-oxo-9H-fluoren-3-yl)benzoic acid (HXL-3W) and 4-(7-(Nbutylcarbazole-3-yl)-9-oxo-9H-fluoren-2-yl)benzoic acid (HXL-4Z), were designed and synthesized through the linking position variation of the fluorenone π-bridge with the N-butylcarbazole donor and a benzoic acid acceptor. The spectra, electrochemistry and photoelectric conversion properties of these carbazole dyes were investigated and their geometric structure and UV-Vis spectra were optimized and calculated using the density functional theory (DFT) method. The results show two distinct absorption peaks, ascribed to the π→π* transition, along with a small peak corresponding to intramolecular charge transfer in the absorption spectrum of HXL-4Z. However, only one π→π* transition absorption peak is found in the spectrum of HXL-3W and its molar extinction coefficient is far smaller than that of HXL-4Z. The reason for this may be a closer distance between the donor and acceptor of HXL-3W leading to a large tension, causing inferior molecular planarity and intramolecular charge transfer. Therefore, HXL-4Z which possesses superior light absorptivity and electron injection efficiency, shows an enhanced photoelectric conversion efficiency of 2.03% (short-circuit photocurrent density (Jsc) = 3.88 mA·cm-2, open-circuit photovoltage (Voc) = 700 mV, fill factor (FF) = 0.75)
%U http://www.whxb.pku.edu.cn/CN/Y2015/V31/I10/1977