Composite Films Based on Carbon Quantum Dots in a Matrix of PEDOT:PSS Conductive Polymer

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 similar to 50 nm. The dependences of the resistivity on temperature, rho(T), are obtained for CQDs, PEDOT:PSS-CQDs, and PEDOT:PSS films, which have a weak activation character. It is found that the rho values of the CQDs films are several orders of magnitude higher than the rho values of PEDOT:PSS films. It is shown that with an increase in the CQDs content in the PEDOT:PSS -CQDs composites, the rho(T) dependences exhibit a transition from high activation energies (similar to 17-18 meV) characteristic of pure PEDOT:PSS to lower values (similar to 10 meV) observed in CQDs films. The mechanism of transport of charge carriers in the investigated materials is considered.