DEVELOPMENT OF CONDUCTING POLYMERS FOR THE TRANSPARENT ELECTRODE OF OPTOELECTRONIC DEVICES

摘要

Optoelectronic devices require at least one electrode to be transparent. Indiun tin oxide (ITO) is traditionally used as the transparent electrode of optoelectronic devices. But ITO has problems of scarce indium on earth and poor mechanical flexibility. New transparent electrode materials are urgently needed. Poly(3,4-ethylenedioxythiophene): poly(styrenesulfonate) (PEDOT:PSS, chemical structure shown in Figure 1) is promising to be the next-generation transparent electrode material due to its solution processability, low cost and high transparency in visible range. However, the as-prepared PEDOT: PSS film obtained from PEDOT:PSS aqueous solution usually has conductivity below 1 S cm~(-1), remarkably lower than ITO. Here, I will present several novel methods to significantly enhance the conductivity of PEDOT:PSS. The conductivity can be enhanced to be more than 3000 S cm~(-1), which is higher than that of ITO on plastic and comparable to ITO on glass. These highly conductive PEDOT:PSS films can be used as the transparent electrode of optoelectronic devices, such as polymer solar cells.