Preparation Of Flexible Transparent Conductive Film And Its Application In OLED Devices

With the continuous advancement of science and technology,display technology is rapidly developed.Nowadays,screens are increasingly pursuing thin,flexible,and active organic lighting.Transparent conductive film?TCF?is an important component of display screens.Whether it is a classic liquid crystal display or a popular active matrix organic light emitting diode?OLED?,the ITO film is still used to prepare the TCF.Commercial indium tin oxide?ITO?used in optoelectronic applications has several drawbacks such as high cost due to indium scarcity and high temperature deposition process,mechanical brittleness,and the complicated manufacturing process where lithographic patterning is needed.Therefore,the development of new flexible TCF with excellent performance has become more and more important.Carbon nanomaterials?carbon nanotubes?CNT?,graphene?are nanomaterials with good mechanical propertie and photoelectric propertie,and have become one of the materials with good development prospects for the preparation of flexible TCF.Firstly,the mechanism of tetrachloroauric?III?acid trihydrate?HAu Cl₄·3H₂O?p-type doping pure carbon nanotube film?CNT TCF?to reduce the TCF sheet resistance was studied in this paper.The surface of the CNT TCF treated with HAu Cl₄·3H₂O contains the Au element,and the signal intensity of the Au element increases as the treatment time increases.Au³⁺obtained electrons from CNT and was partially reduced to Au¹⁺and Au⁰,indicating that HAu Cl₄·3H₂O has a p-type doping effect on CNTs.We found that,when the HAu Cl₄·3H₂O solution was 15 mmol/L and the treatment time was 15 min,the sheet resistance value of CNT TCF decreased to the maximum,and the photoelectric performance of CNT TCF was the best.Secondly,TCF with good conductivity and transparency was prepared by using poly?3,4-ethylenedioxythiophene?:poly?styrene sulfonate??PEDOT:PSS?.PEDOT:PSS is a high conductive polymer with satisfactory light transmittance.The conductivity of PEDOT:PSS TCF was improved by a two-step process which contained adding ethylene glycol?EG?to the PEDOT:PSS solution and sulfuric acid post-treatment.The existence of EG can reduce the Coulomb force between PEDOT and PSS.The PSS was effectively removed and the conductivity of PEDOT:PSS TCF was improve by sulfuric acid treatment.What's more,the mechanism of PEDOT:PSS TCF conductivity enhancement in terms of electrical,optical,structural and compositional characteristics was investigated.Furthermore,P?E,S?/GO-CNT TCF with good optoelectronic properties and mechanical properties was prepared using graphene oxide?GO?,CNT,PEDOT:PSS.Graphene oxide is a chemically modified graphene material which can produce a p-type doping effect on CNTs.The optimal mass ratio of GO to CNT,the effect of EG and sulfuric acid post-treatment on the conductivity of P?E,S?/GO-CNT hybrid film and its mechanism were explored.The final obtained TCF has a sheet resistance of46.3?/sq at a transmittance of 87%?@550 nm?,which indicates that it has great application potential in the field of optoelectronics.Finally,two kinds of TCF were prepared as anodes to prepare OLED devices.The photoelectric properties of the devices were tested.The result show that the prepared films have good application prospects in optoelectronic devices.