Preparation And Photoelectrochemical Study On TiO₂ Nanorods

In this dissertation,TiO₂ nanorods were prepared with a hydrothermal method using TiO₂ nanoparticles.By controlling reaction times,TiO₂ nanorods could be obtained.The photoelectrochemical properties of the pure TiO₂ nanorods.TiO₂ nanorods composite with CdSe nanorods,TiO₂ nanorods modified with poly(3-Methylthiophene)(PMeT) and pure TiO₂ nanorods modified with quantum dot respectively were investigated.The experiment results showed as follows:1)TiO₂ nanorods were prepared with hydrothermal method using TiO₂ nanoparticles. TiO₂ nanorods were ca.50～100 nm in out-diameter,several micrometers to tens in length. The structure of the TiO₂ nanorods is a mixture of an anatase and a rutile phases.The photoelectrical results show that the maximum value of the incident photon to current conversion of efficiency(IPCE) reached 36%.2)The photoelectrochemical properties of the TiO₂ nanorods/Q-CdS were investigated.The photoelectrical results show that the TiO₂ nanorods film electrode modified with CdS quantum dot had higher value of IPCE than pure TiO₂ nanorods film electrode.3)TiO₂ and CdSe nanorods were prepared by hydrothermal method.ITO/TiO₂/CdSe nanostructure composite film with different TiO₂:CdSe molar ratio had been prepared.The photoelectrochemical properties of TiO₂ nanorods film and ITO/TiO₂/CdSe nanorods composite film electrodes were investigated.The ITO/TiO₂/CdSe nanostructure composite film electrode had obvious Hubble effect and higher value of IPCE than TiO₂ nanorods film electrode.The photoelectrochemical results showed that the nanocomposite film maximum value of IPCE reached 66%at 0.5 V.when the mole ratio between ZnO nanocomplex and CdSe nanorods was 2:1.4)The photoelectrochemical properties of the ITO/TiO₂ nanorods/PMeT were investigated. The higher IPCE value for ITO/TiO₂/PMeT film was achieved at-0.4 V.when the polymerization time was 40 s.The results showed that p-n heterojunction was existed in the TiO₂ nanorods/PMeT film.The value of IPCE for PMeT modified TiO₂ nanorods was higher than TiO₂ nanorods film electrode in long wavelength region.5)The photoelectrochemical properties of ITO/TiO₂/CdSe nanostructure composite film and ITO/TiO₂/CdSe/PMeT film were investigated.The experiment results showed that the IPCE of ITO/TiO₂/CdSe/PMeT was obvious increased than that of ITO/TiO₂/CdSe composite film.The experiment results showed that the p-n heterojunction existed in the ITO/TiO₂/CdSe/PMeT nanostructure composite film,which favored the separation of electron-hole pairs generated by photoexcitation.The higher IPCE value for ITO/TiO₂/CdSe/PMeT film was achieved at -0.2 V,when the polymerization time was 40 s.The hybrid solar cell was fabricated with TiO₂/CdSe nanostructure composite film and poly(3-Methylthiophene)(PMeT).The conversion efficiency of the hybrid solar cell was 0.08%,short circurt current 0.61 mA·cm^-2,open circurt voltage 0.4 V,fill factor 0.33. under irradiation of 100 mW·cm^-2 white light from a Xe lamp.