CQD/PEDOT:PSS composites were prepared via the hydrothermal method from glucose carbon quantum dots (CQDs) and an aqueous solution of PEDOT:PSS conducting polymer and their electrical and optical properties were investigated. The morphology and structure of these samples were investigated by AFM, SEM, EDX, and EBSD. It was found that the CQDs and CQD/PEDOT:PSS composites had a globular structure with globule sizes of ~50–300 nm depending on the concentration of PEDOT:PSS in these composites. The temperature dependence of the resistivity was obtained for the CQD/PEDOT:PSS (3%, 5%, 50%) composites, which had a weak activation character. The charge transport mechanism was discussed. The dependence of the resistivity on the storage time of the CQD/PEDOT:PSS (3%, 5%, 50%) composites and pure PEDOT:PSS was obtained. It was noted that mixing CQDs with PEDOT:PSS allowed us to obtain better electrical and optical properties than pure CQDs. CQD/PEDOT:PSS (3%, 5%, 50%) composites are more conductive composites than pure CQDs, and the absorbance spectra of CQD/PEDOT:PSS composites are a synergistic effect of interaction between CQDs and PEDOT:PSS. We also note the better stability of the CQD/PEDOT:PSS (50%) composite than the pure PEDOT:PSS film. CQD/PEDOT:PSS (50%) composite is promising for use as stable hole transport layers in devices of flexible organic electronics.

Carbon quantum dots (CQDs), as well as their composites with the PEDOT:PSS conductive polymer, are hydrothermally synthesized from glucose, and their electrical properties are investigated in the temperature range of 77–280 K. It is shown that the CQDs and PEDOT:PSS–CQDs films have a globular structure with globule sizes of ~50 nm. The dependences of the resistivity on temperature, ρ(T), are obtained for CQDs, PEDOT:PSS–CQDs, and PEDOT:PSS films, which have a weak activation character. It is found that the ρ values of the CQDs films are several orders of magnitude higher than the ρ values of PEDOT:PSS films. It is shown that with an increase in the CQDs content in the PEDOT:PSS–CQDs composites, the ρ(T) dependences exhibit a transition from high activation energies (∼17–18 meV) characteristic of pure PEDOT:PSS to lower values (∼10 meV) observed in CQDs films. The mechanism of transport of charge carriers in the investigated materials is considered.