In order to optimize the working electrode for dye-sensitized solar cells (DSSCs), three kinds of stacked-film structures with the same overall thickness of 13 μm were prepared by using spray coating system, including pure TiO2 film, TiO2-Graphene (TG) film and TiO2/TG (TTG) bilayer film. To increase light path and excite more dye molecules, the bilayer structure of TTG film is composed with TiO2 main layer and TG scattering layer, which provide pores to adsorb N719 dye molecules. The DSSCs with pure TiO2, TG, and TTG working electrodes exhibit the efficiencies of 3.07%, 2.48%, and 4.49%, respectively. From the results, the DSSCs with TG film working electrode had the lowest efficiency, because the TG film had the defects which led to higher interfacial charges than the pure TiO2. Moreover, TTG working electrode contained a TiO2 main layer and a TG scattering layer in which the graphene material could increase the electron transport and reduce the recombination, and it was also due to the stacked structure, which could improve the light utilization and enhance the light transmitting distance. In this article, the working electrode of DSSCs was successfully modified by using TTG stacked structure with an improved efficiency of 46.25% higher than that of TiO2 working electrode.

中文翻译：

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TiO2/TiO2-石墨烯双层结构用于优化染料敏化太阳能电池工作电极


为了优化染料敏化太阳能电池（DSSC）的工作电极，采用喷涂系统制备了三种总厚度相同为13 μm的叠层薄膜结构，包括纯TiO2薄膜、TiO2-石墨烯（TG）薄膜。 ）薄膜和TiO2/TG（TTG）双层薄膜。为了增加光程并激发更多的染料分子，TTG 薄膜的双层结构由 TiO2 主层和 TG 散射层组成，提供了吸附 N719 染料分子的孔隙。具有纯 TiO2、TG 和 TTG 工作电极的 DSSC 的效率分别为 3.07%、2.48% 和 4.49%。从结果来看，具有TG薄膜工作电极的DSSC效率最低，因为TG薄膜存在缺陷，导致界面电荷高于纯TiO2。此外，TTG工作电极包含TiO2主层和TG散射层，其中石墨烯材料可以增加电子传输并减少复合，而且由于堆叠结构，可以提高光利用率并增强光通量传输距离。本文利用TTG堆叠结构成功修饰了DSSCs的工作电极，其效率比TiO2工作电极提高了46.25%。