Water-processable nanocomposite based on polyaniline and 2D molybdenum disulfide for NIR-transparent ambipolar transport layers

Polymer nanocomposite based on stable water-dispersible polyaniline complex with poly(2-acrylamido-2-methyl-1-propanesulfonic acid) (PANI–PAMPSA) and 2D molybdenum disulphide (MoS₂) was developed. The nanocomposite layers obtained by drop-casting were characterized by Vis–NIR- and FTIR spectroscopies, as well as by atomic force, transmission electron, and Kelvin-probe microscopies, X-ray diffraction, cyclic voltammetry, Hall effect, and DC-conductivity measurements. It was shown that the preparation procedure allows easy adjusting of MoS₂ content in the nanocomposite resulting in the growth of DC conductivity by up to six times in the case of 20 wt% MoS₂ as compared with the additive-free PANI–PAMPSA complex. FTIR spectroscopy revealed the existence of hydrophobic interactions between PANI–PAMPSA and 2D MoS₂ nanophase, which facilitate interchain electron transfer. Hall effect studies showed that while increasing MoS₂ content in the nanocomposite, a transition occurs from monopolar hole transport, characteristic of PANI–PAMPSA, to ambipolar transport. This feature makes the obtained PANI–PAMPSA/MoS₂ composite a promising material for different optoelectronic devices, in particular tandem solar cells.     

Chemical polymerization of aniline in the presence of mixtures of polymeric sulfonic acids

The template polymerization of aniline in the presence of polymeric sulfonic acids of various structures and their mixtures is studied. In the latter case, the dominant effect of a polyacid on the kinetics of aniline polymerization and the electronic structure of the resulting polyaniline complex is observed. As shown by viscometry measurements and IR studies, the intermolecular interaction between polyacids in their mixtures that leads to a change in the conformation of a flexible-chain polyacid is responsible for the dominant effect of a rigid-chain polyacid. The spectral and electrical properties of polyaniline-based interpolymer complexes are examined.