Application Of Mesoporous Ti-Sn Composite Oxides In Dye-Sensitized Solar Cells

With the rapid consumption of fossil fuels,the exploration of clean and renewable energy has become an important research topic at this stage.Solar energy is used as an excellent alternative to fossil energy because of its abundant energy reserves and the characteristics of green and environmental protection.Photovoltaic power generation directly converts solar energy into electrical energy,which is the core of solar energy application research.As an important device in photovoltaic power generation,solar cells have attracted the attention of researchers.The dye-sensitized solar cell,one of the third-generation solar cells,has a relatively simple manufacturing process and a low cost price.The photoanode is an extremely important component and a key element that determines the photoelectric conversion efficiency of the dye-sensitized solar cell.In the choice of photoanode semiconductor materials for dye-sensitized solar cells,the metal oxide Sn O₂has stable chemical properties and fast electron transmission speed.Ti O₂has stable chemical properties and good photoelectric properties.The mesoporous composite material of Sn O₂and Ti O₂is prepared,which not only has the characteristics of high specific surface area,but also has the excellent performance of each material,and can be used as an excellent material for photoanode.In this paper,the hard template method was used to synthesize mesoporous tin dioxide(Meso-Sn O₂),and Meso-Sn O₂was doped with Ti O₂by the incipient wetness dipping method to prepare Mesoporous Ti-Sn Composite Metal Oxide(Ti O₂-Meso-Sn O₂).Ti O₂-Meso-Sn O₂composite material with high specific surface area,uniform pore size,excellent morphology and good dispersion was synthesized,explored the influence of precursor type,calcination temperature,Ti O₂content.Then a series of tests such as photoelectric performance test,incident photon-electron conversion efficiency(IPCE)test,electrochemical impedance spectroscopy(EIS)test,etc.were carried out to verify its application prospects in dye-sensitized solar cells.The specific work is as follows:(1)Using KIT-6 as a template,Meso-Sn O₂was successfully synthesized by the hard template method.Exploring the influence of calcination temperature(400?,500?,600?,700?)on the structure and morphology of Meso-Sn O₂,it is found that700?is the best temperature for calcination.The high specific surface area is 132.4m²/g,the large pore volume is 0.41 cm²/g and the uniform pore size is 2.77 nm.(2)Ti O₂-Meso-Sn O₂was prepared with Ti(OC₂H₅)₄and Ti(OCH(CH₃)₂)₄as precursors,and the dispersibility was good.The material synthesized with Ti(OC₂H₅)₄as the precursor exhibits a relatively larger specific surface area and pore volume.(3)Exploring the influence of different calcination temperatures(350?,400?,450?)on the structure and morphology of Ti O₂-Meso-Sn O₂,and found that 400?is the best calcination temperature.The specific surface area and pore volume of the obtained product are higher than those calcined at the other two temperatures,and the dispersibility is better.(4)Prepare Ti O₂-Meso-Sn O₂with different amounts of Ti O₂.When the content is20 wt%and 30 wt%,the diffraction peak of Ti O₂can be clearly seen in the XRD image.When the content of Ti O₂is 20 wt%,the specific surface area and pore volume are larger than the content of 30 wt%,which are 96.3 m²/g and 0.15 cm³/g..and It can be seen from the SEM image that the prepared material has good dispersibility and uniform morphology.(5)The(JV)curve test,(EIS)test,(IPCE)test,and(UV-vis)test were performed on the DSSCs prepared from the above samples.When Ti O₂-Meso-Sn O₂with a Ti O₂content of 20 wt%was added,The best photovoltaic performance of DSSCs was obtained,the highest PCE is 1.95%,which is about 3 times that of pure Sn O₂material,and it also shows the highest current density of 7.45 A/cm².