Dye-sensitized thin film solar cells which brought about revolutionary innovation fordevelopment of photoelectrical chemical cells and been keystone of energy technology infuture as a new generation of solar cells with low price and high performance gained largeattention from many people. However, sensitized dye as an important component of DSSCadopted organic dye generally with high price, difficult source and poor long stability.Therefore inorganic sensitized dye got large attention, especially inorganic semiconductorFeS2 as sensitized dye with high absorbance coefficient (whenλ≤700nm,α≥5×105cm-1) and appropriate band gap(0.95eV).TiO2 films with compact base, porous surface were prepared by sol-gel and powdercoating on ITO conducting glass. FeS2 films were formed on surface of TiO2 films by solutiondipping method. Thus, FeS2/TiO2 composite films could be gained, which as inorganicsensitized dye realized the purpose of sensitizing DSSC. Crystal under different transformingtemperatures of TiO2, surface and cross section morphology of compact and porous structureof TiO2 films, crystal under different annealing conditions and surface morphology of FeS2films, absorbance and thickness of FeS2/TiO2 composite films, resistance of ITO conductingglass before and after sinter, and performance of DSSC were investigated by DTA, XRD,SEM, UV-vis, thickness measurement, four probes surveying resistance apparatus and solarcells testing instrument.The result shows: Compact base and porous TiO2 films electrode can be prepared at550℃by 5℃/min, 30min heat preservation, then cooling spontaneously. Surface morphology,thickness and absorbance of FeS2/TiO2 films change according to concentration of FeS2starting solution, dipping time, annealing temperature condition. When 0.1mol/l concentrationof FeS2 starting solution, 3h dipping time, 20min heat preservation at 500℃by 15℃/minunder sulfur atmosphere. FeS2/TiO2 films electrode with uniform distributing crystal particles,moderate thickness, favorable absorbance can be obtained. Under this condition performanceof DSSC is better. FeS2/TiO2 composite films which were prepared through appropriateconcentration of FeS2 starting solution, dipping time, annealing temperature condition can improve evidently the Isc, Voc and realize the purpose of sensitize by using FeS2 as inorganicdye. This can conquer a series of problems which were brought about by organic sensitizeddye and is a significant explore and attempt for utility of DSSC.
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