Synthesis Of Polyaniline Intercalated Graphite Oxide Composite And Its Use As Electrolyte In Soiled State DSSCs

Because of the growing demand for energy, combined with the depletion of fossil resources, global warming and its associated climate change, the development of clean alternatives to current power generation methods is immensely important in order to preserve the global environment and assure sustained economic growth. Solar cells, where electricity is generated directly from sun light, promise to offer a clean solution to the energy crisis. Since the great breakthrough made by O’Regan and Gratzel,dye-sensitized solar cells (DSSCs) have attracted much attentions because of their high energy conversion efficiency and low production cost, making them a credible alternative to silicon solar cells. The focus of research on dye-sensitized solar cells (DSSCs) has shifted recently from those based on liquid electrolytes to quasi solid-state cells, because of the technological problems associated with the liquid electrolytes, such as hermetic sealing of the cells, evaporation of liquids at high temperatures, permeation of water and oxygen molecules into the electrolyte. Conducting polymer polyaniline (PANI) has been studied widely because of its good processibility, environmental stability and potential technological importance in the fields of catalysis, biosensors, batteries, and electronic technology. With unique structure and outstanding physical chemical properties, graphene oxide rapidly become the hot topics of the chemistry,physics,biology and material science, especially in which way they reinforce polymer nanocomposites.So,the mains results from those studies are summarized as following:1. An improved method for preparation of graphene oxide (GO) and graphene by our group. XRD analysis and TEM microphotograph demonstrated that the distance of the GO sheets was about0.8nm.The preparation and research of GO films shew us that there was lots of organic oxygenic groups in the basal planes of GO.Because of the organic oxygenic groups, the dispersivity properties of GO got prodigious improving. Through TGA and Raman analysis, we could know that the deoxidized graphene incomplete reductioned.2. PANI/GO composites were synthesized in acidic condition and basicity condition, respectively. XRD analysis demonstrated that PANI were coating GO in composites in acidic condition. Compared with that, PANI were intercalating GO to form composites in basicity condition. FT-IR authenticated that through reaction and re-doped with acid, GO in the composites were reactioned partly. SEM and TEM microphotograph demonstrated that through reaction and re-doped with acid, the molecular chain of polymer were expanded. TGA analysis demonstrated with the addition of GO, the thermal stability of PANI/GO composites rose one after the other. Electrochemical Measurement indicated when the component of GO was about10wt%, electrochemical properties of composites was well. Ⅰ-Ⅴ characteristics told us that when the component of GO was about10wt%and re-doped with HC1, the result could get the optimum value:Voc=0.41V, η(%)=0.16%, JSc=1.04mA cm-2, at the same condition but in the basicity condition, we could find that power-conversion efficiency was stabely with the addition of GO.3. PANI/PVA/GO composites were synthesized. XRD images demonstrated the parallel and vertical distance of PANI chains in PANI/PVA composites and through reactioned, the composites got shipshaper structure. FT-IR authenticated that there were no chemical bond between PANI and PVA. SEM and TEM microphotograph demonstrated that the dimensions of polymer changed because of the existance of PVA. TGA analysis demonstrated the thermal stability of PANI/PVA/GO composites descended because of the existance of GO. But through reaction and re-doped with acid, he thermal stability rose considerably ad. Electrochemical Measurement indicated when the component of GO was about3wt%to5wt%, electrochemical properties of composites was best. Ⅰ-Ⅴ characteristics also told us that, when the component of GO was about10wt%, the DDSCs got best power-conversion efficiency, Voc=0.39V, Jsc=1.03mA cm-2.The FF of the composites re-doped with HI was preferably.4. P(An-co-oAs) composites were synthesized by PANI and PoAs monomer in acidic condition. Then, P(An-co-oAs) and GO were synthesized to P(An-co-oAs)/GO composites. XRD images demonstrated P(An-co-oAs) composites kept the mode of parallel structure in the layer of GO. FT-IR demonstrated that chains of composites from bend to extending state.-NH group in P(An-co-oAs) composites could form H bond with the layer of GO. TEM microphotograph demonstrated that few P(An-co-oAs) composites successfully intercalated GO. TGA analysis demonstrated H bond between PANI and PoAs made the composites more stability. Through I-V characteristics, we knew that when the component of GO was about5wt%, the DDSCs got best power-conversion efficiency, Foc=0.38V, JSc-0.74mA cm-2,η(%)=0.16%.