Study On The Solar Cells With MoS₂ As Photoelectric Transport Material

In this thesis,a hybrid solar cell was fabricated with the TiO₂ nanorod array as window material,the narrow-bandgap semiconductor of Sb2S3 nanostructure as photosensitizer,and the P3HT-MoS₂ microheterostructure prepared by introducing a novel photoelectric transport material of MoS₂ into P3HT through ultrasonic dispersed method as hole transport layer.The formation and the function mechanism of the P3HT-MoS₂microheterostructure in the solar cell were explored.The photovoltaic performance of the solar cell was optimized.The p/n semiconductor characteristics and the energy level structure of the as-prepared MoS₂ were investigated by photoelectrochemical measurement,which could provide a theoretical basis for the application of MoS₂ in solar cells.Different methods,such as SEM,TEM,EDS,XRD,were utilized to characterize the as-prepared MoS₂ and P3HT-MoS₂ microheterostructure.The results indicated that the as-prepared MoS₂ was a kind of p-type semiconductor material.The energy level of the as-prepared MoS₂ was matched with that of TiO₂,Sb₂S₃ and P3HT.The P3HT-MoS₂ microheterostructure could be successfully formed through dispersed the MoS2 into the P3HT through ultrasonic.Theoretically,it is feasible that the designed P3HT-MoS₂ microheterostructure was used as hole transport material in the solar cell.In order to obtain better photovoltaic performance,the photoelectric performance of the TiO2 nanorod array was optimized.The morphology and structure of the TiO2nanorod array were controlled by changing the hydrothermal time,precursor concentration,seed layer thickness and calcination temperature.The as-prepared TiO2 nanorod array were characterized by SEM and XRD and the photoelectric performance of different samples were investigated by photoelectrochemical measurement.The results showed that the TiO₂ nanorod arrays with most ideal photoelectric property could be prepared with the followed condition:two-layer seed layer,precursor concentration of 450?L/40 mL,hydrothermal reaction at 170?for 200 min and calcination at 450?for 30 min.A hybrid solar cell based on the photoactive layer of P3HT-MoS₂/Sb₂S₃/TiO₂ was fabricated,in which the optimized TiO2 nanorod array,the Sb2S3 nanostructure and the P3HT-MoS₂ microheterostructure were used as window material,photosensitizer and hole transport layer,respectively.The energy conversion efficiency of solar cell based on P3HT-MoS2/Sb2S3/TiO2 could reach 3.22%,which is 40%higher than that of the solar cell based on P3HT/Sb2S3/TiO2.The function mechanism of the P3HT-MoS2microheterostructure was systematically studied through UV-vis absorption,PL and EIS spectra.The results revealed that the P3HT-MoS₂ microheterostructure could offer better absorption performance and favorable energy alignment to facilitate the separation and transport of photogenerated charges.The improved charge carrier mobility and the reduced charge recombination efficiency could then result in an enhanced energy conversion efficiency of the solar cell.