Application Of Carbon Materials Counter Electrodes For Dye-sensitized Solar Cells

In recent years, DSC has attracted much attention due to its simple production procedure, environmental friendliness, high power conversion efficiency, and relatively low cost. Generally, a DSC contains three components, a photoanode, a CE, and an electrolyte. TiO2is widely used as the semiconductor, bipyridyl carboxylate ruthenium is used as the dye, electrolyte commonly comprises I3-/I-redox couples. Pt is generally used as the CE catalytic material. However, Pt is an expensive noble metal with limited reserves. Moreover, it can be corroded in I3-/I-electrolyte, influencing the stability of the DSC. Therefore, it is imperative to develop Pt-free catalytic materials that show the merits of high activity, abundant reserves, low cost, and strong erosion resistance to reduce the DSC cost as well as to improve its stability.Catalytic activities of three kinds of carbon materials were compared systematically under the same conditions. These carbon materials contained activated carbon, conductive carbon, carbon nanotube. The experimental results revealed that the catalytic performance of conductive carbon was worst, its battery efficiency was only2.13%, battery efficiency of activated carbon was2.23%, the carbon nanotube had the highest catalytic efficiency, battery efficiency was3.06%. The carbon nanotube performed best amongst these carbon materials. Moreover, the catalytic mechanism of the catalytic materials for the regeneration of the conventional redox couples (I3-/I-) was investigated by electrochemical impedance spectroscopy, cyclic voltammetry, and Tafel-polarization curve experiments.In a word, three low cost Pt-free catalytic materials were designed for the DSC. As a result, we were able to expand the range of CE catalytic materials and reduce the cost of production for this device.