N3/Al2O3/N749交替组装结构拓宽准固态染料敏化太阳能电池光响应范围和界面修饰效果

研究了染料敏化太阳能电池(DSCs)中N3/Al₂O₃/N749交替组装结构的作用. 该结构使用Al₂O₃作为介质层吸附第二层染料, 可以有效拓宽DSCs的光响应范围, 提高电池的光电转化效率. UV-Vis 吸收光谱和单色光转换效率(IPCE)谱测试结果表明, 相对于单一染料, 使用交替组装结构的电池光响应范围变宽. 电流-电压(I-V)曲线结果表明, 该结构有效增加了DSCs 电池的光电转化效率, 从单一N3 和N749 染料的4.22%和3.09%增加到了5.75%, 分别增加了36%和86%. 为了研究该结构的作用机理, 本文对其界面修饰作用及界面电子过程进行了讨论. 暗电流测试结果表明交替组装结构可以有效阻止电荷复合过程; 电化学阻抗谱(EIS)结果表明在黑暗条件下, N3/Al₂O₃/N749结构可以提高界面电阻, 从而抑制电荷复合过程; 本文建立了等效电路模型, 并使用该模型讨论了交替组装结构的界面电子过程; 调制强度光电流谱(IMPS)和调制强度光电压谱(IMVS)的结果表明该结构可以提高电子寿命和改善电子扩散.

N3/Al2O3/N749 Alternating Assembly Structure Broadening the Photoresponse and Interface Modification Effects in Quasi-Solid Dye-Sensitized Solar Cells

In this paper, the interface modification effects and electron processes in N3/Al₂O₃/N749 alternating structured dye-sensitized solar cells (DSCs) were studied. UV-Vis absorption and monochromatic incident photon-to-electron conversion efficiency (IPCE) spectra showed that the N3/Al₂O₃/ N749 structure broadened the photo-response range. Photocurrent-voltage (I-V) curves showed that enhanced conversion efficiencies were obtained. Compared with N3- and N749-only structures, the efficiency of the N3/Al₂O₃/N749 structure increased from 4.22% and 3.09% to 5.75% (36% and 86% enhancement), respectively. From electrochemical impedance spectroscopy (EIS) results, the N3/Al₂O₃/ N749 structure displayed increased interface resistance under dark conditions. This indicates that charge recombination is reduced in the N3/Al₂O₃/N749 device, which was confirmed from the dark current measurements. Furthermore, to analyze the electron processes, a series of equivalent circuit models were built to mimic the injection and recombination process in DSCs. Intensity modulated photocurrent spectroscopy (IMPS) and intensity modulated photovoltage spectroscopy (IMVS) also showed that this structure improved the electron life time and diffusion.