Efficient Dye-Sensitized Solar Cells with Highly Catalytic Pt-Deposited ZnO/FTO Counter Electrode

The development of novel cathode is essential for developing high performance dye sensitized solar cells (DSSCs). Here, Pt-coated ZnO nanostructures are used as cathodes of DSSCs to increase their photovoltaic performances. The ZnO nanostructures are grown by chemical bath deposition method, and then Pt is deposited on the nanostructured ZnO substrates. The scanning electron microscopy analyses show that nanostrcutrured Pt-deposited ZnO/FTO is well-formed on fluorinated tin oxide (FTO) substrate with yielding high surface area. The increase in the surface area of Pt-deposited ZnO/FTO leads to the high electrochemical kinetics for reduction of I3- to I-. As a result, the optimized Pt-deposited ZnO/FTO cathode shows the high photovoltaic performances of DSSCs about 6.70% of overall power conversion efficiency, which is 52% higher than the DSSCs using typical Pt-deposited FTO cathode.