Abstract
In this study, we focus on the effect of adding silver nanowires in the TiO2 electrode of the dye-sensitized solar cell. The silver nanowires were synthesized by Polyol process. The synthesized silver nanowires have a diameter about 100 nm and a wide distribution of lengths, from several microns to about 30 microns. The synthesized silver nanowires were coated with a thin layer of TiO2 to prevent erosion by the electrolyte and also to prevent the fuse of the nanowire during the annealing process. The amounts of the silver nanowires added to the TiO2 electrode is from 1 wt% to 4 wt% and the TiO2 film thickness was varied from 8μm to 30μm. It was found that adding 3 wt% silver nanowires for the 10 micron thick film achieve the highest efficiency. The efficiency is increased from 4.68% to 5.31%. According to the results of IPCE and EIS measurements, the improvement of efficiency can be attributed to the reduction of the internal impedances and the enhancement of the electron transport. For thicker films or higher amounts of added silver nanowires, the efficiency would decrease which could be due to the increase of light absorption. Other than the addition of silver nanowires, tests were also made with the addition of silver nanodiscs, which possesses double absorption peaks. Due to the small amounts of the synthesized silver nanodiscs, tests were made for adding only 0.1 wt% silver nanodiscs and it was found that the efficiency can be slight increased.