Figure 3 Current density-voltage ( J -
V ) characteristics of DSSCs based on PEDOT/FTO, TiO 2 -PEDOT:PSS/PEDOT:PSS/glass, STA-9090 and Pt/FTO CEs. Table 2 The performances of dye-sensitized solar cells with different CEs measured under an AM 1.5G illumination Counter electrode V oc (V) J sc (mA cm−2) FF η (%) PEDOT:PSS/FTO 0.72 11.63 0.43 3.64 TiO2-PEDOT:PSS/PEDOT:PSS/glass 0.73 12.45 0.51 4.67 Pt/FTO 0.75 10.54 0.63 5.11 Conclusions In summary, we utilize a facile wet method to fabricate a novel hierarchical Pt- and FTO-free CE for the dye-sensitized solar cell. It is found that the TiO2 doped PEDOT:PSS catalytic activity layer will dramatically affect the electrochemical properties of the final device. By adjusting the composition of TiO2, the properties of CE have been optimized preliminarily. Because of the large active area of TiO2 nanoparticles, the proposed composite CE shows excellent enhancement in the conductivity and the superior catalytic activity for the reduction of I3 − to I−. The conversion efficiency is increased
by 22% than that of the DSSC with PEDOT:PSS/FTO CE and is comparable to that of the DSSC with traditional Pt/FTO CE. After further optimization, the TiO2-PEDOT:PSS/PEDOT:PSS/glass CE can be more cost-effective, high efficient, and flexible to replace Pt and FTO CEs and more broadly used for future commercial applications. Acknowledgements We acknowledge the support partly from the National Natural Science Foundation of China (grant nos. 91333122, 51372082, 51172069, 50972032, 61204064, PLX3397 buy Paclitaxel and 51202067), the Ph.D. Programs Foundation of Ministry of Education of China (grant nos. 20110036110006, 20120036120006, and 20130036110012), and the Fundamental Research Funds for the Central Universities. References 1. O’Regan B, Grätzel M: A low-cost, high-efficiency
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