| Growing problem of energy shortage and environmental polution forced people to develop and ultilize renewable energy. As a clean renewable energy,solar energy has become the research hotspot in this field. After years of efforts, so far solar cells has developed to the third generation, dye-sensitized solar cells,which is the powerful competitor to silicon-based solar cells because its advantages of simple preparation technology, low-cost and zero pollution to the environment, thought as the most prosperous solar cell as well.The main component of dye-sensitized solar cells is Nano semiconductor thin film. Usually, film electrode is made by nano-TiO2semiconductor material,however, pure nano-TiO2film electrode is constrained by the factors just like limition of absorption spectrum, electron-hole recombination, leading to the photoelectric conversion efficiency cannot be improved significantly.The paper mostly studied on film photo-anode of dye-sensitized solar cell,firstly nano-TiO2sol was prepared with sol-gel method.Then ZnO nanorods made by hydrothermal synthesis method,Carbon nano tubes (CNTs) and commercial P25powder used as carriers, prepared loaded type of nano TiO2thin film, chrarcerized by X-ray diffraction (XRD),assembled dye-sensitized solar cell,photoelectric performance tests and analysis were further proceeded.(1) ZnO nanorods were made as carriers under different alkalinity conditions through hydrothermal synthesis method, mixed with nano-TiO2made by Sol-Gel,afer processing the nano-TiO2loaded onto the surface of ZnO nanorods. Prepared supported ZnO/nano-TiO2thin film electrode,microstructure were characterized by XRD, the photoelectric performance test to the assembled DSSC. The characterization showed that sol-gel method of nano-TiO2has the advantages of small particle size is bigger than surface area, and the orientation of ZnO nanorods generated alkali conditions grow more clearly, make electronic quickly import base along a straight line, increases the electron transfer rate through the Ⅰ-Ⅴ test shows that alkali conditions generated by the ZnO nanorods as the carrier has a better preparation of DSSC photoelectric properties, open circuit voltage short-circuit current1.42mA/cm2and0.56V, the photoelectric conversion efficiency than under the conditions of weak alkali preparation of ZnO nanorods made after load DSSC improved nearly1times.(2) CNTs were used as carriers with mass fraction of0.1%,0.15%,0.2%afer dispersing, mixed with nano-TiO2made by Sol-Gel,afer processing the nano-TiO2loaded onto the surface of CNTs. Prepared supported CNTs/nano-TiO2thin films electrode, microstructure were characterized by XRD, the photoelectric performance test to the assembled DSSC. The characterization showed growth with the increase of CNTs mass fraction, nano-TiO2is restrained and turing smaller particle size, whicn can increase the specific surface area of the films.Because the CNTs have apparent pipeline structure, conducive to inhibit electron-hole recombination, reduces the electronic transmission loss. But with the increase of mass fraction, in the process of thin film surface get dark gradually, increase the CNTs with dye molecules of light absorption of competition, to some extent reduced the photoelectric conversion efficiency of DSSC. Test through the Ⅰ-Ⅴ curves prove that the mass fraction of0.1%CNTs DSSC photoelectric performance of the preparation of nanometer TiO2optimal load, short circuit current and open circuit voltage are1.69mA/cm2and0.54V, with the photoelectric conversion efficiency of0.52%, more than two other DSSC improved30%and85%.(3) With commercial P25as the carrier, and sol-gel method of nanometer TiO2colloid mixture, after processing the nano TiO2loading to P25particles on the surface of nano TiO2thin film electrode preparation of P25load type, of their microstructure were characterized through XRD, for DSSC photoelectric performance test after assembly. Characterization showed that P25added to strengthen the cohesive strength between TiO2nanoparticles, increases the specific surface area of membrane; At the same time, particle size slightly larger P25can improve the degree of dense membrane, good light transmission and scattering effect, improve the utilization rate of light. Based on the three different carrier mention above, preparation of DSSC curve fitting and found three kinds of support after the nano TiO2preparation of DSSC is approximately the same open circuit voltage are around0.55V, but obvious changes have taken place in short circuit current, among them with P25as the carrier preparation of DSSC has the maximum short-circuit current, which is2.03mA/cm2. Photoelectric conversion efficiency is0.62%, compared with the DSSC prepared by the ZnO nanorods and CNTs as carriers the efficiency increased by35%and19%respectively. |
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