Preparation And Optoelectronic Properties Of PEDOT:PSS/Copper Nanowires Composite Transparent Conductive Electrode

Organic light-emitting diode?OLED?has many advantages,such as self-luminescence,ultrathin,high contrast,low energy consumption,simple structure and so on.In recent years,it is remarkably promising display device.OLED transparent anode materials usually use Indium Tin Oxides?ITO?,but ITO itself is fragile,expensive,and the preparation process needs high temperature deposition under vacuum environment,which cannot meet the needs of flexible,impact resistance and low-cost flexible equipment.Therefore,people urgently need to seek alternative materials that are cheap,flexible,simple preparation process,well compatible with flexible substrate and can be large-scale production.Copper nanowires?CuNWs?composite transparent conductive electrode is fully in line with the above requirements.This paper mainly uses a simple hydrothermal synthesis method for the growth of CuNWs with controllable length,ultralong,thin,good dispersivity and study the morphology of CuNWs products under different reaction conditions.A copper nanowires composite transparent conductive electrode with low square resistance and high transmittance is prepared by using a growing CuNWs,and used as an transparent anode in a flexible green light OLED device.The main contents are as follows.Firstly,We use hydrothermal synthesis to grow CuNWs,ascorbic acid?C₆H₈O₆?as the reducing agent,eighteen alkyl amine(C₁₈H₃₉N,ODA)as the capping agent,copric?II?chloride dihydrate?CuCl₂·2H₂O?to provide the source of copper.By constantly adjusting the experimental parameters,SEM,TEM,XRD,and optical microscopy are used to characterize the production.The effect of different reaction time,ODA,ascorbic acid,different reaction temperature to the reaction products are researched.The resulting CuNWs average length of about 100?m,average diameter about 35nm,and the ratio of length to diameter is about 2857.Secondly,The CuNWs prepared by the hydrothermal synthesis method are applied to fabricate flexible copper nanowires transparent conductive electrode on PET by the vacuum filtration transfer method,which exhibit excellent conductivity-transmittance performance with low sheet resistance of 26.23?/sq and high transparency at 550 nm of89.06%.However,the transparent conductive electrode still exist some fatal disadvantages,such as easy oxidation,surface roughness,and it cannot meet the practical application of OLED devices.Therefore,in order to overcome the above problems,we fabricate the CuNWs/PMMA composite transparent conductive electrode by spin coating polymethyl methacrylate?PMMA?solution with excellent chemical stability on the surface of the copper nanowires transparent conductive electrode.The surface roughness of the composite transparent conductive electrode is greatly reduced and the antioxidant capacity is significantly improved.Thirdly,Although the CuNWs/PMMA composite transparent conductive electrode has excellent photoelectric properties,the work function of the transparent electrode is still very low.In order to improve the work function of CuNWs/PMMA composite transparent conductive electrode,we fabricate the CuNWs/PMMA/PEDOT:PSS compositetransparentconductiveelectrodebyspincoatingPoly?3,4-ethylenedioxythiophene?/poly?styrenesulfonate??PEDOT:PSS?on the surface of the CuNWs/PMMA composite transparent conductive electrode.A flexible green light OLED device with CuNWs/PMMA/PEDOT:PSS/NPB?50nm?/Alq3?40nm?/Li F?1nm?/Al?100nm?is prepared with this composite transparent conductive electrode as transparent anode,and compared with the flexible green light OLED device with PEDOT:PSS electrode as anode.The experimental results show that the OLED device with composite transparent conductive electrode as transparent anode shows maximum luminance of 2385cd/m² and maximum current density of 509mA/cm²,which have been enhanced by 104%and 400%,respectively,as compared with those?1169cd/m² and102mA/cm²?of device with PEDOT:PSS electrode as anode.