Retardation of Charge Recombination Between Hole Conductors and TiCI4:BaCl2-Modified Photoelectrodes in TiO2-Based Solar Cells

作者：Kim Myung Hwan; Shin Dong Won; Lee Se Won; Kwak Giseop; Lee Sang Ju; Kim Dae Hwan; Sung Shi Joon^*; Han Yoon Soo^*

来源：Journal of Nanoscience and Nanotechnology, 2017, 17(11): 8144-8148.

DOI：10.1166/jnn.2017.15090

• Surface Modification
• TiCI4
• BaCl2
• Mixed Overlayer
• Dye-Sensitized Solar Cells

The effects of a mixed overlayer composed of TiO2 and BaTiO3 on the performance of dye sensitized solar cells (DSSCs) were investigated. The surfaces of TiO2 photoelectrode films were modified with TiCl4:BaCl2 mixed aqueous solutions with various molar ratios and then calcined to produce surface-modified TiO2 photoelectrodes (Ti:Ba TiO2/FTO). The resulting films were applied to the photoelectrodes of DSSCs. The DSSCs with Ti:Ba(3:7) TiO2/FTO, which were prepared from a mixed solution with a molar ratio of 3:7 (TiC14:BaCl2), showed a power conversion efficiency of 8.99% compared with the 8.23% conversion efficiency of the reference cell with Ti:Ba(10:0) TiO2/FTO (i.e., a TiO2-only overlayer), due to enhancements in the short-circuit current (J) and the open-circuit voltage (Voc). A series of measurements, including those on ultraviolet-visible absorption, electrochemical impedance, and dark currents, revealed that the incorporation of the mixed overlayer on the nanoporous TiO2 photoelectrodes led to improvements in the light harvesting efficiency and the electron collection efficiency, thereby increasing the J(sc), value. The increase in the V, value of the device with Ti:Ba(3:7) TiO2/FTO was caused by the reduced charge recombination between the photo-injected electrons and I-3(-) ions.

• 出版日期2017-11