Enhanced efficiency in dye-sensitized solar cells based on TiO2 nanocrystal/nanotube double-layered films
Enhanced efficiency in dye-sensitized solar cells based on TiO2 nanocrystal/nanotube double-layered films
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DOI：
10.1016/j.electacta.2009.11.067
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发表时间：
2010-02
影响因子：
6.6
通讯作者：
Hui Xu;Xia Tao;Dong-Ting Wang;Yan‐Zhen Zheng;Jianfeng Chen
中科院分区：
文献类型：
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作者：
Hui Xu;Xia Tao;Dong-Ting Wang;Yan‐Zhen Zheng;Jianfeng Chen
制备了一种以 TiO2 纳米晶体为底层、TiO2 纳米管为上层的新型双层结构薄膜。所得到的双层TiO2（DL-TiO2）薄膜由于其协同效应，即有效的染料吸附主要来源于TiO2纳米晶体层和一维TiO2纳米管层中的快速电子传输，可以显着提高染料敏化太阳能电池（DSSC）的效率。 DL-TiO2薄膜形成的总能量转换效率（η）为6.15%，比纯纳米晶TiO2（NC-TiO2）薄膜形成的能量转换效率高44.7%，远高于纳米管TiO2（NT-TiO2）薄膜形成的能量转换效率（η=0.37%）。通过电化学阻抗谱研究了电池的电荷复合行为，结果表明DL-TiO2薄膜电池具有最低的传输电阻和最长的电子寿命。入射光子-电流效率光谱表明，对于DL-TiO2、NC-TiO2和NT-TiO2基太阳能电池，宽带几乎覆盖了400至700nm的整个可见光谱，在~530nm波长处的最大值分别为57.3%、40.3%和2.2%。预计双层膜电极可以扩展到具有不同层结构和形貌的其他复合膜，以提高 DSSC 的效率。
A new bilayer-structured film with TiO2nanocrystals as underlayer and TiO2nanotubes as overlayer was fabricated. The resultant double-layer TiO2(DL-TiO2) film could significantly improve the efficiency of dye-sensitized solar cells (DSSCs) owing to its synergic effects, i.e. effective dye adsorption mainly originated from TiO2nanocrystal layer and rapid electron transport in one-dimensional TiO2nanotube layer. The overall energy-conversion efficiency (η) of 6.15% was achieved by the formation of DL-TiO2film, which is 44.7% higher than that formed by pure nanocrystalline TiO2(NC-TiO2) film and far larger than that formed by nanotube TiO2(NT-TiO2) film (η=0.37%). The charge recombination behavior of cells was investigated by electrochemical impedance spectra, and the results showed that DL-TiO2film-based cell possessed the lowest transfer resistance and the longest electron lifetime. The incident-photon-to-current efficiency spectra indicated that the broad bands covered almost the entire visible spectrum from 400 to 700nm with the maxima of 57.3%, 40.3%, and 2.2% at a wavelength of ∼530nm for DL-TiO2-, NC-TiO2-, and NT-TiO2-based solar cells, respectively. It is expected that the double-layer film electrode can be extended to other composite films with different layer structures and morphologies for enhancing the efficiencies of DSSCs.