Study On Dye-sensitized Solar Cells Performance By The Magnetic Field Influenced

The horn of energy crisis has sounded in every corner of the world, solving the energyproblem becoming a sacred mission to scholars from various countries. Solar energy is aninexhaustible clean energy and can be seen everywhere, so using it effectively is an importantway to solve the energy problem. The dye-sensitized solar cells (DSSCs) have been got everyresearcher’s attention, which is attributed to the relatively high photon-to-current conversionefficiency, the low cost, simple fabrication and non-toxic/non-pollution et al. So far, a simpleway, using magnetic field, to improve the TiO2-based the DSSCs is very scarce. This paperimproves the DSSCs photovoltaic performance mainly through two different ways: externaland internal magnetic field, which is beneficial for its faster practice.Firstly, the external magnetic field effect on TiO2-based DSSCs in was studied. Theresults showed that in different fields, the photoelectric conversion efficiency of the cells isdifferent, and the optimal performance is appeared with the magnetic field of45mT. Inaddition, when the performance is decreased after long-term operation, it is recovered with45mT magnetic field and remains it for some time after the magnetic field wasdisappeared.There are two reason can explain it: one is the transport of electrons and holes indifferent directions with an external magnetic field, reducing recombination and improvingthe electron lifetime, thereby resulting the high conversion efficiency; another is theincomplete depolarization lead to the performance is not decreased instantaneously.γ-Fe2O3、α-Fe2O3nanoparticles is synthetized through coprecipitation method andhydrothermal method, respectively. α-Fe2O3@TiO2/γ-Fe2O3@TiO2core-shell structures weresynthesized by the versatile kinetics-controlled coating method, and doped into TiO2filmswith different structure and concentration. Surface image is observed by SEM and TEM, andcomposition is analyzed using XRD and EDX pattern. Moreover, we measured the magneticproperties of γ-Fe2O3@TiO2.At last, we also studied the performance of DSSCs, which is influenced by an internalmagnetic field (ferromagnetic γ-Fe2O3). The result shows: although the photoelectricperformance has little improved, the stability is very bad. However，not only does theperformance of DSSCs have much enhanced, but also the stability is very good by dopingγ-Fe2O3@TiO2. At the same time, the energy conversion efficiency of DSSCs is6.01%whenthe doping concentration is1.5%at the second floor. The internal magnetic field effect onenergy conversion efficiency of DSSCs is analyzed and the internal mechanism is studied.Magnetic field is in the internal of cells through ferromagnetic nanoparticles, which provideconvenience for the new type cells using.