Tandem Dye-sensitized Solar Cell Based on Metal Mesh

A newly structured tandem dye-sensitized solar cell (tandem DSC) based on stainless mesh was introduced, in which the electrode constituted a first TiO2 film on TCO and a second TiO2 film on stainless mesh. Negative inter- action between different dyes in this structure is less than that by normal method of cocktail-dyes dipping. The appli- cation of stainless mesh here reduces the loss of incident light, solves the problem of electronic connection between two different TiO2 films, as well as improves electron transport and collection. This tandem cell achieved a power conversion efficiency of 1.96% with short circuit current density of 8.4mA/cm 2 . Compared with normal mono-layer DSC with similar cell thickness, efficiency was improved about 62% by this tandem structure. Electrochemical im- pedance spectroscope (EIS) was used to analyze the electron transport in tandem DSC, and an equivalent circuit for tandem DSC was also proposed here. Meanwhile, the increased cell thickness and electron recombination on the sur- face of the stainless mesh have obvious influence on the photovoltaic performance.