由于一维(1D)氧化钛纳米结构具有提高染料敏化太阳能电池(DSCs)中的电子传输性能从而进一步提高电池性能的特性,该领域吸引了越来越多研究者的关注.但是一维氧化钛纳米结构如何影响电子传输性能却少有报道.本研究利用电化学阻抗谱(EIS)分析来探索氧化钛纳米颗粒和纳米管复合薄膜的电子传输特性.使用两种不同尺寸(25和100nm)的纳米颗粒和纳米管作为原料,采用电泳沉积方法制备了氧化钛复合薄膜并研究了原料的组成对染料敏化电池的影响以获得最佳的组成.研究结果表明,在大颗粒的质量分数低于20%时,大颗粒的掺入有利于改善氧化钛薄膜的电子传递与电池性能.与完全由颗粒组成的薄膜相比,纳米管的加入有利于电子在氧化钛薄膜里的传输.纳米管、100nm颗粒及25nm颗粒的最佳质量比例为20:16:64.
As one-dimensional(1D) TiO2 nanostructures can benefit charge transport and improve the performance of dye-sensitized solar cells(DSCs),they have attracted much attention recently.However,studies on how 1D nanostructures affect the charge transport have rarely been reported.In this study,an electrochemical impedance spectroscopy(EIS) analysis was carried out to scrutinize the charge transport properties of a TiO2 particle-titania nanotube composite film.The composite TiO2 film was prepared by electrophoretic deposition using two kinds of nanoparticles with different sizes(25 and 100 nm) and titania nanotubes(TNTs) as the starting powder.The influence of the powder's composition on DSCs based on the composite film was investigated to yield an optimum composition.It was found that large particles(LPs) increase the charge diffusion and cell performance before the mass fraction of the large particles reaches 20%.Compared with films fully consisted of particles,TNTs prove to facilitate electron transport within the TiO2 film.The optimum mass ratio of TNTs:LPs:PPs(25 nm particles) is 20:16:64.