Performance Optimization Of The Dye-sensitized Solar Cells By TiO₂ Nanotubes Decorated With Au-nanoparticles

Dye-sensitised solar cells(DSSCs)have recently received much concern as a new renewable energy and also have been considered the ideal alternatives to silicon-based solar cells on account of their special performances,such as simple process,low cost,environmentally friendly and the high photoelectric conversion efficiency.In this dissertation we explore the effect of one-dimensional structure such as TiO2 nanotubes(TNT)and TiO2 nanotubes embedding gold nanoparticles(TNT-Au)on the performance of the dye sensitized solar cells,and further optimizing the performance of dye-sensitized solar cell in improving the utilization of sunlight,accelerating the transmission rate of photoelectrons.TiO2 nanotubes(TNT)with high electron transfer rate and light scattering effect can enhance the capture rate of the light anode to incident light and electronic transmission,we prepare the TNTs in alkaline solution by hydrothermal method,the effect of different concentrations of TNT on the performance of DSSCs is also investigated.Our results indicate that,the Voc of 675mV,the maximal Jsc of 12.95mA cm-2 and PCE of 6.01%are obtained in the optimal DSSC with 10wt%TNT,which is significantly higher than those of the DSSCs with pure TiO2 photoanode.Au nanoparticles possess local surface plasmon resonance absorption effect,we decorate the TiO2 nanotubes(TNT)with Au nanoparticles,forming a TNT-Au composite,and the influences of different concentrations of TNT-Au on the performance of the multifunctional composite photoanodes and DSSCs are investigated.When incorporated 10wt%TNT-Au,the optimal value of DSSC with Jsc of 14.72 mA cm-2 and PCE of 6.94%are obtained,which are significantly higher than that of the DSSC with pure TiO2 photoanode by 24.3%and 21.8%,respectively.Importantly,TNT with unique hollow structure and the excellent properties of charge transfer and strong scattering of incident light,increasing the electron transfer rate and the ability of capturing the incident light to photo-anode.Au nanoparticles embedded in TiO2 nanotubes behave phenomenal surface plasmon resonance absorption effect,which promotes the local surface plasmon resonance,and thus enhancing the performance of DSSC.This research gives a further improvement and new way to improve the photoelectric conversion efficiency of DSSCs.