The application of fluorine-modified PEDOT:PSS on recovering the S-shaped curve and improving reliability for the organic solar cells

• Main Authors: Chi-Ang Tseng, 曾祈昂
• Other Authors: Chia-Chun Chen
• Format: Others
• Language: zh-TW
• Published: 2010
• Online Access: http://ndltd.ncl.edu.tw/handle/74422659993801226020

碩士 === 國立臺灣師範大學 === 化學系 === 99 === In this study, we investigate the s-shape recovery and the improvement of reliability of the fluorine-modified poly(3,4-ethylene dioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) buffer layer based on poly(3-hexylthiophene) (P3HT) and [6,6]-phenyl-C61-butyric acid methyl ester (PCBM) blends polymer photovoltaic cells. The results of humidity-controlled experiments show that the degradation of the device performance can be recovered simply by the interfacial modification, even though the PEDOT:PSS layer has been seriously deteriorated by the air ambient. The anomalous S-shape photocurrent owing to the deterioration of the PEDOT:PSS layer can be rectified significantly as an ideal diode behavior by the surface treatments with fluorine-containing materials. Accordingly, the great enhancements of Fill factor from 30% to 62% can be achieved, where the efficiency is improved from 1.90% to 4.09%. The mechanism is due to the interfacial dipole and hydrophobicity generating by fluorine-modified PEDOT:PSS layer. Moreover, the reliability of the devices with modification shows significant increase than those without modification. The efficiency of the modified devices retains about half (1.9%) of its initial efficiency (4.1%) after 30 days compared to the unmodified one (0.6%). This phenomenon is investigated and reported for the first time. Furthermore, the overall device performance is also enhanced by ~20% as compared with the control device.