The main goal of this work was to modify activated carbon (AC) with carbon nanodots (C-dots) and to explore the modified composites as electrode materials for supercapacitors. C-dots were synthesized by sonication of polyethylene glycol followed by sonochemical modification of AC matrices with the preprepared C-dots. Sonication introduces the C-dots into the pores of the AC. The effect of the introduction of the C-dots into the AC and their incorporation into the pores was studied. The porosity of the AC/C-dots and the AC reference materials was explored, as well as the impact of the C-dot loading on the performance of the electrodes comprising these AC/C-dots. It was found that the AC/C-dot electrodes demonstrate a specific capacitance of 0.185 F/cm2 (per specific electrode area), three times higher than the capacitance of unmodified AC electrodes per specific electrode's area. It was established that the new electrode's material, namely, AC/C-dots, exhibits very stable electrochemical behavior. Many thousands of cycles could be demonstrated with stable capacity and a Coulombic efficiency of around 100%.
Bibliographical noteFunding Information:
D.A. acknowledges the partial support for this work obtained from the ISF, Israel Science Foundation, in the framework of the INREP project. We also acknowledge support by the Israel Ministry of Science and Space
© 2016 American Chemical Society.