Mixed interlayers at the interface between PEDOT:PSS and conjugated polymers provide charge transport control

作者：Moule Adam J^*; Jung Min Cherl; Rochester Chris W; Tress Wolfgang; LaGrange Daniela; Jacobs Ian E; Li Jun; Mauger Scott A; Rail M Diego; Lin Oliver; Bilsky David J; Qi Yabing; Stroeve Pieter; Berben Louise A; Riede Moritz

来源：Journal of Materials Chemistry C, 2015, 3(11): 2664-2676.

DOI：10.1039/c4tc02251c

Poly(3,4-ethylenedioxythiophene)-poly(styrenesulphonate) (PEDOT:PSS) is the most used organic hole injecting or hole transporting material. The hole carrying matrix PEDOT is highly doped by the acidic dopant PSS. When coated onto a substrate, PEDOT: PSS makes a highly uniform conductive layer and a thin (<5 nm) overlayer of PSS covers the air interface. Semiconducting polymer layers for organic photovoltaics or light emitting diodes are coated on top. In this article, we demonstrate that the PSS layer will mix with almost all conjugated polymers upon thermal annealing. Depending on the Fermi energy of the polymer an electrochemical reaction can take place, p-type doping the polymer at the interface between the PEDOT: PSS and the semiconducting polymer. We use chemical and spectroscopic analysis to characterize the polymer/PSS interlayer. We show that the stable and insoluble interlayer has a great effect on the charge injection and extraction from the interface. Finally we demonstrate and electronically model organic photovoltaic devices that are fabricated using these mixed interlayers.

• 出版日期2015