Pt/PEDOT Composite Materials Fabricating And Their Application In Dye–sensitized Solar Cells

Energy is the basic factor for the development of human society.However,the conventional fossil fuels are rapidly depleting,raising the need for the exploration and use of renewable energy.Dye sensitized solar cells?DSSCs?have attracted considerable attention in recent years as a viable energy alternative among various photoelectric devices because of the merits of environmental friendliness,simple fabrication process,and building integrated photovoltaic?BIPV?.DSSCs is generally composed of a photoanode?dye-sensitized TiO₂ film?,a counter electrode?CE?,and an electrolyte containing a redox couple?iodide/triiodide?.Fabrication of qualified mesoporous TiO₂ films as well as excellent catalytic performance of the counter electrode materials is crucial because the photoanode determine the power conversion efficiency?PCE?of the device to a large extent.To date,the doctor-blading and screen-printing methods are still commonly used techniques to prepare TiO₂ films.However,the procedures of fabricating multilayer TiO₂ films with screen-printing or doctor-blading is complicated,which contains many steps,e.g.the fluorine-doped tin oxide?FTO?glass has to be coated with TiO₂paste several times with screen printing technique to obtain the required thickness.That restrictes the large-scale promotion of DSSCs to some extent.Moreover,the counter electrode is mostly metal platinum Pt material.As is known,platinum is precious metal,which is very expensive and limited.Meanwhile,platinum is easily corroded by I₃^-/I^-in the electrolyte,which affected the stability of DSSCs.Therefore,in order to reduce the cost of DSSCs and improve its stability,and is more benefical to large-scale production,it becomes extremely urgent to develop more efficient,low cost,rich reserves and corrosion-resistant non-platinum catalyst materials or Pt-containing composite counter electrode catalyst materials.Firstly,a method for Fabricating TiO₂ film with a facile spray-coating technique for dye-sensitized solar cells is introduced.The performance of the DSSCs is tested by various methods.And then,the advantages and disadvantages of the spray coating method as well as traditional screen printing method and doctor-blading method are compared.Compared with other preparation methods,the mesoporous TiO₂ film prepared by spraying method has higher specific surface area and porosity,and the charge transfer rate is more faster.This shows that the spray coating method is a more ideal preparation process of TiO₂ film.The photoelectric conversion efficiency PCE reached 7.1%by spraying method.Secondly,poly?3,4-vinyl dioxythiophene??PEDOT?was synthesized by electrochemical deposition and which is applied to DSSCs.The catalytic performance is characterized by cyclic voltammetry method and electrochemical impedance spectroscopy?EIS?.By adjusting the electrochemical deposition time?40 s,80 s,120 s,160 s?and adjusting the preparation conditions of PEDOT,the energy conversion efficiency?PCE?of the dye-sensitized solar cells achieves 7.56%,which is very close to Pt counter electrode material.The result shows a better photocatalytic performance.This widens the choices of counter electrode materials for the dye-sensitized solar cells.Finally,Pt/PEDOT composites material is prepared by cyclic voltammetry method,and the catalytic properties of PEDOT and Pt are investigated,respectively.The Pt/PEDOT composites material prepared by cyclic voltammetry is applied to DSSCs,and the energy conversion efficiency reaches 7.90%,which exceeds Pt counter electrode.