The Preparation Of SnO₂/RGO Photoanode And Its Effect On The Property Of Dye-sensitized Solar Cells

Dye-sensitized solar cells?DSSCs?have been the most industrialized foreground because of their advantages of easy operation,low cost and designable structure.Photoanode has been attracted popular attention because of its importance for the photoelectric property of DSSCs.Thus,in this work efforts have been make to prepare new nanocomposites to improve photoelectric performance of DSSCs.The graphene oxide?GO?has been synthesized from natural graphite by a modified Hummer's method.Then the SnO₂/RGO nanocomposites which SnO₂ and reduced graphene oxide support to each other in this composite were prepared in hydrothermal process via assisted reduction of bivalent tin ion on graphene oxide.The structure and morphology of the samples were tested by X-ray diffraction?XRD?,scanning electron microscope?SEM?and transmission electron microscope?TEM?.The results show that SnO₂ particles were uniformly dispersed on the RGO sheets and there are about ten layers of RGO sheet and every layer thickness of about 0.35 nm.The different mass ratio of SnO₂/RGO colloid was synthesized by traditional sol-gel method.Then the thin films were uniformly spread on the surface of the precleaned FTO glass by the screen printing technique,and sintered at 450? in air.Subsequently,the prepared photoanode was soaked in N719 dye solution at room temperature.Finally,the DSSCs were assembled with SnO₂/rGO photoanode,Pt counter electrode and electrolyte solution for further characterization.The photoelectric performance?J-V curves?and charge transfer behavior?EIS?of assembled DSSCs were tested.According to the results,the PCE of DSSCs firstly increases and then decreases with the increase of the proportion of GO.The photoelectric conversion efficiency was up to 4.58%when the mass ratio of GO was 20%.In addition,the DSSC has the smallest charge transfer resistance and longest electron lifetime when the mass ratio of GO was 20%.Therefore,the nanocomposites are beneficial to improve the photoelectric performance of SnO₂-based DSSCs.