The Reseach Of The Dye-sensitized Solar Cells Carbon Nitride Electrode

Dye-sensitized solar cells(Dye-sensitized Solar cells, DSSCs) is a new type of highly efficient Solar Cells. Platinum( Pt) is widely used in the electrode of DSSCs for high catalytic activity and high conductivity. But because of Pt is expensive, so looking for cheap nonplatinum counter electrode is becoming a research hotspot in recent years. In this paper, we prepared porous carbon nitride and its composite materials. Applied the materials to the DSSCs counter electrode and studied their electric catalytic properties.Through high temperature carbonization and soft template method prepared many kinds of non-porous and porous carbon nitride materials, and they show good photo-electrochemical performance as the DSSCs counter electrode. Among them the porous carbon nitride which using melamine as raw materials through the soft template method prepared show the highest photoelectric conversion efficiency, it can reach to 2.07%, indicating that large specific surface area is beneficial to improving the electrical catalytic properties of carbon nitride.The porous carbon nitride / conductive carbon black composite materials is prepared by grinding method and they show good catalytic activity and excellent electrical conductivity. Including them when the mass ratio of carbon nitride and conductive carbon black is 1 : 7, the composite materials has the best electrochemical performance, and the photoelectric conversion efficiency can reach to 4.74%, which is the 93.12% of Pt electrode in the same conditions.The oxidation of graphene is prepared by the graphite, then using the hydrothermal method to prepare the carbon nitride / graphene composite materials. They show good performance in the aspect of photo-electrochemical. The results display that when the mass ratio of carbon nitride and graphene is 3 : 1, the photoelectric conversion efficiency of the composite materials can reach to 4.47%, which is the 88.17% of the Pt electrode in the same conditions.The carbon nitride / multi-walled carbon nanotubes composite materials are prepared by high temperature carbonization method. They show good performance in electrocatalys, and they have excellent electrical conductivity, by analyzing the photoelectric performance testing results obtain that when the mass ratio of cyanamide and multi-walled carbon nanotubes is 15 : 1, the composite materials has the highest photoelectric conversion efficiency, and it can reach to 4.49 %, which is the 86.68% of Pt electrode in the same conditions.