ИСТИНА

The creation of hybrid composites combining the advantages of both organic and inorganic materials is of great interest for modern optoelectronics. In the report, the effect of 2D materials on optical, electrical properties and frontier electron levels of composites based on a water-soluble polyaniline complex (PANI) with polymeric sulfonic acid is considered. Graphene of various oxidation states and graphene-like molybdenum disulfide (MoS2) and tungsten disulfide (WS2) were used as 2D materials. The created composites were investigated by electron spectroscopy and X-ray analysis. The results of measurements of electrical conductivity, mobility and concentration of charge carriers (4-probe method, Hall Effect) showed the influence of the 2D materials on the flow of electric current in layers of the composites. The increase of the MoS2 and WS2 nanophase concentration was found to change the type of major charge carriers in the nanocomposites. By using Kelvin-probe microscopy the work function distribution on the composite layers was investigated. It was shown that the work function of graphene is higher than that of PANI, and therefore, the former can create relatively deep electronic states in the composite. The composites used as a charge-transport layer in organic solar cells increased the extraction of holes from photoactive layer and, as a result, the performance of the devices. Since the work function of 2D MoS2 and WS2 is lower than that of PANI, the composites exhibit ambipolar conductivity above the threshold concentration of the 2D materials. Such composites are of interest for use as a connecting interlayer in tandem solar cells.