Study On Aligned Carbon Nanotubes And Graphene Counter Electrode Of Dye-sensitized Solar Cells

Dye-sensitized solar cells(DSSCs)have caused extensive attention of researchers from all over the world,due to its environmental friendliness,low production cost and simple process.Counter electrode is an important component of DSSCs,its materials and preparation process are the important factors to affect the performance of the counter electrodes and DSSCs.In this paper,in order to achieve the purpose of reduce the cost,improve power conversion efficiency(PCE)and promote industrialization,counter electrode was set out to study.The main content is as follow:1.Aligned carbon nanotubes(ACNTs)were used to be counter electrode materials in this study,but ACNTs have a high tendency to form agglomerates,which will damage the electrocatalytic activity of ACNTs.In this work,ACNTs were functionalized by polyethylene glycol octylphenol ether(Triton X-100),poly(3,4-ethylenedioxythiophene)/poly(styrenesulfonic acid)(PEDOT:PSS)and the blends of these two substances,then the functionalized ACNTs were applied in DSSCs.Although the dispersion of PEDOT:PSS functionalized ACNT is the worst,it present many big hole on its surface,which make electrolyte easier to permeate into counter electrode,leading to the best electrochemistry properties of this ACNT counter electrode,besides,PEDOT:PSS itself has excellent conductivity,so the DSSC based on PEDOT:PSS functionalized ACNT counter electrode showed the best.In addition,through changing process of counter electrode,we found that the ACNT counter electrode prepared by spraying possess better performance,the PCE of DSSC base on this counter electrode improved to be 3.15%from 2.96%.So we continue prepared graphene counter electrode by spray method.2.Just like carbon nanotube,graphene also have a high tendency to form agglomerates.In this work,Reduced graphene oxide(RGO)was functionalized by polyethylene glycol octylphenol ether(Triton X-100),cetylpyridinium chloride(CPC)and sodium dodecyl benzene sulfonate(SDBS).In addition,for improving the adhesion of RGO,ACNT were precoated on the FTO glasses in this work,and the functionalized RGO/ACNT bilayer structure counter electrodes were prepared through spray coating.The results indicated that the dispersion of CPC/RGO is the best and the corresponding DSSC shows optimal PCE of 3.90%.3.RGO was continued to serve as counter electrode material,CPC,PEDOT:PSS and PANI functionalized RGO counter electrodes were prepared through electrophoretic deposition.The results indicated that graphene layers of PANI/RGO spread more completely,and corresponding DSSC showed the highest PCE of 3.78%.In addition,because of the excellent conductivity of PEDOT:PSS,the DSSC based on PEDOT::PSS counter electrode also showed good PCE of 3.76%.