Nanocrystal Decorated Titanium Dioxide And Its Application In DSSC

Dye sensitized solar cells(DSSCs) as a new novel type of solar cell have been regard as the most possibility to be the third generation solar cell. It has the advantages of relative low production cost, easily accessible and high energy conversion efficiency. Among DSSCs, the photoanodes are important components which adorbing the dye molecules, thus, the photoanodes have great effect on DSSCs.Commercial titanium dioxide P25have been widly used for DSSC, but P25have large pore diameter and much defect. This paper used titanium(Ⅳ) bis(ammonium lactato) dihydroxide (TALH) as precursor via a process of controlled hydrolysis and condensation, modified the P25with nanocrystals. The mass ratio of nanocrystals was30wt%(30-P25) having the small pore diameter. The30-P25photoanode was smooth and achieve the cell efficiency of6.83%which was28%higher than the P25photoanode.Incorporation of scatterers into photoanode films has been used as an effective strategy to enhance the light utilization. Especially, the high refractive index of rutile TiO2affords superior light scattering characteristics, beneficial for light harvesting. However, rutile TiO2has the high sintering activity. The specific surface aera of rutile TiO2was heavily decreasing after sintering. What’s more, the scattering layer had the large particle diameter compared to porous layer. The remarkable crack occurs when the films sintered at high temperature due to the different shrinkage rate between particles. This paper coated the nanocrystals on rutile nanorod microsphere and commercial submicron TiO2respectively. The specific surface area of anatase TiO2nanocrystals coated rutile TiO2nanorod microsphere(NCRNM) was50%increment compared to that of rutile TiO2nanorod microsphere(RNM). The efficiency of DSSC assembled by anatase TiO2porous layer and NCRNM scattering layer was7.33%, which was7%increment compared to that constituted of RNM scattering layer; By coating of TiO2nanocrystals on the commercial submicron TiO2(NCS-TiO2) the specific surface was increased from5.5m2/g to16.7m2/g. The presence of TiO2nanocrystals in NCS-TiO2also had the highly sintering activity and reduced the sintering stress between porous layer and scattering layer. The crack-free photoanodes of DSSCs with NCS-TiO2as scattering layer showed the efficiency of8.36%.