Research On Sulfide Electrode Materials Of Dye-sensitized Solar Cells

With the development of the global economy and the advancement of civilization,humankind’s thirst for clean energy is increasingly intensified.Dye-sensitized solar cells（DSSCs）have attracted widespread attention due to their potential for environmental protection and low cost,and have become the focus of recent years.Research hotspots.DSSC is mainly composed of three parts:dye-sensitized nanocrystalline thin film electrode（such as the most commonly used FTO/TiO₂ electrode）,electrolyte and counter electrode（such as the most commonly used FTO/Pt electrode）.How to improve the performance and reduce the cost is the core content of current DSSC electrode materials research,which is of great significance for promoting the large-scale application of DSSC.The most common material for the counter electrode is noble metal platinum（Pt）,but due to the limited storage of platinum,its price is particularly expensive,so the development of cheap and efficient new counter electrode materials,to reduce the cost of DSSC,and promote dye-sensitized solar energy The large-scale application of batteries is of great significance.This paper mainly studies the counter electrode materials of dye-sensitized solar cells.We have synthesized two inexpensive and high-efficiency counter electrode materials,which are regular NiS submicron square counter electrode materials and TiS₂ counter electrode materials with two-dimensional layered structures.We systematically studied the preparation and related properties of NiS and TiS2materials with specific morphology.1.Preparation and properties of NiS submicron cubes.We systematically studied the preparation methods of NiS.Using NiSO₄·6H₂0 and NaOH,which are easily available and inexpensive,we used the simple hydrothermal method to synthesize a NiS submicron cubic counter electrode material with a regular shape.This cube has a diameter of approximately 300-800 nm and is used as a counter electrode assembly battery for various performance tests.The test results are compared with Pt for the counter-electrode battery,and it is found that various properties have greatly improved.In order to further improve the performance of the synthesized NiS,we found that after sintering in an argon gas stream at a high temperature of 400℃.for one hour,the shape of the NiS remains unchanged and still maintains a regular cubic shape,and relative to the unsintered NiS exhibits superior optical and electrical properties.This low-cost NiS submicron cube has the potential to become a replacement material for traditional Pt electrodes.2.Preparation and properties of two-dimensional nano-TiS2 materials.We systematically studied the preparation method of TiS₂.We found that solvothermal method can be used to synthesize two-dimensional nano-ultra-thin TiS₂ material at a temperature of 200°C.This material possesses similar morphology to graphene.Its thickness is between 1-10 nm and its diameter is about 1-2μm.Each piece of TiS₂ nanosheet consists of one or more layers of TiS2 single crystal flakes.The 20μm thick TiS₂ sheet resistance we synthesized is 7.1Ω·m^-2,which is nearly double that of the conventional Pt electrode 14.2Ω·m^-2.This two-dimensional nano-TiS₂ material not only has good conductivity,but also has excellent electrocatalytic properties,and can be used as a cheap and highly efficient counter electrode material for dye-sensitized solar cells.