PEDOT∶PSS 柔性电极及其发光电化学池的制备和性能

Fabrication and Performance of Flexible Electrodes and LEC Devices Based on PEDOT:PSS for Gravure Printing

摘要:

采用凹版印刷工艺制备了聚(3,4-乙烯二氧噻吩):聚(苯乙烯磺酸)（PEDOT:PSS）透明电极，并实现柔性图案化发光电化学池（LEC）器件的制备。本研究首先通过氧等离子体处理聚对苯二甲酸乙二醇酯（PET）表面，并结合溶剂掺杂调控PEDOT:PSS墨水，最终在PET基底上采用凹版印刷制备了PEDOT:PSS透明电极，并利用甲酸（HCOOH）后处理提升电极性能。结果表明，氧等离子体处理显著提高了PET表面的润湿性，乙二醇（EG）掺杂有效改善了PEDOT:PSS墨水的成膜性和导电性，经甲酸后处理得到高导电性（方阻为380 Ω/sq）、高透过率（88.06%）的PET-PEDOT:PSS电极。该电极在不同机械弯曲角度下，经过600 s弯曲测试后仍能保持良好的电学性能。最终，在大气环境下，以PET-PEDOT:PSS透明电极作为阳极，采用全溶液法成功制备了底部发光的柔性LEC器件，其亮度达到110.4 cd/m2。此外，基于丝网印刷图案化特性，制备了图案化显示的LEC器件。所制备器件在30°、45°、60°弯曲角度下，仍展现出优良的发光特性。

Abstract:

Gravure printing was employed to fabricate transparent electrodes based on poly(3,4-ethylenedioxythiophene):polystyrene sulfonate (PEDOT:PSS), enabling the development of flexible, patterned light-emitting electrochemical cell (LEC). The process began with oxygen plasma treatment of polyethylene terephthalate (PET) to enhance surface wettability, followed by solvent doping to optimize the properties of the PEDOT:PSS ink. Transparent PEDOT:PSS electrodes were gravure printed on PET substrates and their performance was further enhanced by post-treatment with formic acid (HCOOH). It was found that oxygen plasma treatment significantly improved the wettability of the PET surface, whereas ethylene glycol (EG) doping enhanced the film-forming properties and conductivity of the PEDOT:PSS ink. The post-treatment with formic acid resulted in a PET-PEDOT:PSS electrode with high conductivity (sheet resistance of 380 Ω/sq) and high transmittance (88.06%). After 600 s of mechanical bending at various angles, the electrode retained stable electrical performance. Finally, using the PET-PEDOT:PSS electrode as the anode, a flexible bottom-emitting LEC was successfully fabricated under ambient conditions by a fully solution-processed method, achieving a brightness of 110.4 cd/m2. In Addition, a patterned LEC device was fabricated using the patterning capability of screen printing, which exhibited excellent luminescent performance at bending angles of 30°, 45°, and 60°.