Preparation And Performance Of Photoanode Matericals For Dye-sensitized Solar Cells

The preparation of TiO2particles (nanoparticles, microspheres), and theirapplication in DSSC were investigated in the papre. Experimentally, micro-emulsionand hydrothermal method were used to synthesize TiO2nanoparticles. The experimentparameters and the properties for the application on DSSC were discussed. In theother experiment, another hydrothermal system was used to synthesize TiO2microspheres and apply on DSSC scattering layer. The main contents are discussed asfollowing.TiO2nanoparticles were prepared through micro-emulsion and differentsurfactants and the amount of additives were discussed to control the morphology ofTiO2nanoparticles. The different size of TiO2nanoparticles ranging in the10~15nmand20~25nm were prepared using CTAB and Tx-100as the surfactants. Theelectrodes, which were designed with the two size of TiO2nanoparticles, were used toassemble DSSCs, and got7.38%conversion efficiency with the size of20~25nm TiO2nanoparticles.TiO2nanoparticles were prepared through hydrothermal method using tetrabutyltitanate as precursor, and diethylene glycol (DEG) as the additive. TiO2nanoparticleswith the size of about20nm, high crystallinity of anatase, and less surface defectswere synthesized. When hydrothermal reaction, the disperse property of TiO2wasinfluenced by the temperature, reaction time, and pH. The kind of additives caninfluence lattice structure and defect. Hence, on the condition of220℃,16h, pH=12,and the amount of additive with DEG: TiO2=2:1(molar ratio), the synthesized TiO2nanoparticles have good disperse property, low defects density, ordination crysaillinewith (101) crystal face exposed in the surface, and good transferring of electron.DSSC fabricated with the TiO2nanoparticles electrode showed a good conversionefficiency of7.90%.TiO2spheres with the rough surface, which assembled by the TiO2nanoparticleswere prepared through hydrothermal method using TiCl4, ethanol, and K-30asprecursor. The amount of K-30impacts on the size of TiO2spheres. We got the size ofabout400nm,1μm,3μm TiO2spheres by changing the amount of K-30.DSSCs were fabricated by two layers, one layer was transparent layer synthesized by TiO2nanoparticles, and the other was scattering layer synthesized byTiO2spheres. The two-layer structure can make the use of light reflection caused byTiO2spheres and the dye adsorption caused by TiO2nanoparticles. As a result, theDSSC shows a conversion efficiency of8.11%.