面向器件应用的PEDOT:PSS薄膜的光电稳定性研究

PEDOT:PSS(聚3, 4-亚乙基二氧噻吩-聚苯乙烯磺酸盐)薄膜因其良好的导电性、透光性、机械柔韧性以及溶液可加工性而被广泛应用。提高PEDOT材料的电导率以及光电稳定性对其器件应用有重要意义。在本文中,首先用旋涂法制备PEDOT:PSS薄膜,然后采用硫酸后处理技术提高其电导率,并将硫酸处理后的薄膜分别放置于空气、氧气、氮气中以及太阳光照下30 d,研究薄膜的光电稳定性及老化机制。实验结果表明:太阳光照是影响薄膜光电性能稳定性的主要因素,而硫酸处理有效地去除了过量的PSS成分,使薄膜的稳定性变好。通过比较老化前后薄膜的光吸收谱和光电子能谱(XPS)发现,在老化过程中薄膜发生了光氧化降解,这是影响薄膜光电稳定性的原因之一。

Photo-Electrical Stability of PEDOT:PSS Thin Film for Device Application

PEDOT∶PSS(poly 3,4-ethylenedioxythiophene-polystyrene sulfonate) film is widely used due to its good electrical conductivity, light transmittance, mechanical flexibility and solution processability. Improving the electrical conductivity and photoelectric stability of PEDOT materials is of great significance to its device applications. In this article, highly conductive PEDOT∶PSS films were obtained by spin-coating method after post-treatment by sulfuric acid. The films were placed in air, oxygen, nitrogen and under sun illumination for 30 d to study their photo-electrical stability and aging mechanisms. It indicates that: sunlight is the main factor affecting the stability of photo-electrical properties of thin films, and sulfuric acid treatment removes the excessive PSS component effectively and therefore improves the stability of PEDOT∶PSS films. By comparing the absorption spectrum and photoelectron spectroscopy(XPS) of the film before and after aging, it is found that, the film underwent photo-oxidation degradation during the aging process, which directly affects its photoelectrical stability.