Composite films based on carbon quantum dots in a matrix of PEDOT:PSS conductive polymer

Carbon quantum dots (CQDs) and their composites with the conducting polymer PEDOT: PSS were obtained by the hydrothermal method from glucose, and their electrical properties were investigated in the temperature range 77–280 K. CQDs have a globular structure with globule sizes of $\sim$ 50 nm. The dependences of the resistivity on temperature, $\rho(T)$, have been obtained for the films of CQDs, PEDOT:PSS-CQDs and PEDOT: PSS, which have a weak activation character. It was found that the $\rho$ values of the CQD films are several orders of magnitude higher than the $\rho$ values of the PEDOT: PSS films. It has been shown that with an increase in the content of CQDs in the PEDOT:PSS-CQDs composites, the $\rho(T)$ dependences exhibit a transition from high activation energies ($\sim$ 17–18 meV), characteristic of pure PEDOT: PSS, to lower values ($\sim$ 10 meV) observed in CQD films. The mechanism of transport of charge carriers in the investigated materials is considered.