Structure and properties of highly conductive langmuir-blodgett films based on dioctyldimethylammonium-Au(dmit)₂ salt

Langmuir-Blodgett (LB) films of dioctyldimethylammonium-Au(dmit) ₂ [2C₈-Au(dmit)₂] salt show a relatively high room-temperature conductivity of up to 17 S/cm. The conductivity is as high as 50 ± 23 S/cm after electrochemical oxidation. A distinct absorption band is seen at 287 nm and it increases linearly with the number of layers, indicating a reproducible film deposition for up to 20 layers. During the post-treatment, the absorption peak decreases together with some shoulders and a broad band appears in the near-infrared (NIR) region with an isosbestic point at 609 nm, indicating the formation of conduction electrons. The UV/visible absorption spectrum changes markedly in the first 60 min of the post-treatment and becomes almost constant later, which corresponds well with the change in conductivity during the post-treatment.