AUTHOR=Tobis Maciej , Sroka Sylwia , Frąckowiak Elżbieta 

TITLE=Supercapacitor with Carbon/MoS2 Composites

JOURNAL=Frontiers in Energy Research

VOLUME=Volume 9 - 2021

YEAR=2021

URL=https://www.frontiersin.org/journals/energy-research/articles/10.3389/fenrg.2021.647878

DOI=10.3389/fenrg.2021.647878

ISSN=2296-598X

ABSTRACT=Transition metal dichalcogenides (TMDs) with a two-dimensional character are promising electrode materials of electrochemical capacitor (EC) owing to their unique crystallographic structure, available specific surface area and large variety of compounds. Our study shows a hydrothermal L-cysteine assisted synthesis of two composites based on different carbon materials – multiwalled carbon nanotubes (NTs) and carbon black (Black Pearl-BP2000), on which MoS2 nanolayers were deposited. The samples were subjected to physicochemical characterization such as X-ray diffraction (XRD) and Raman spectroscopy which proved that the expected materials were obtained. Scanning electron microscopy coupled with electron dispersive spectroscopy confirmed composites made of disordered MoS2 nanolayers deposited on the carbon supports. The synthetized samples were employed as electrodes materials in symmetric ECs and their electrochemical performance was evaluated and compared to their pure carbon supports. Among the composites, NTs/MoS2 demonstrated the best electrochemical metrics considering the conductivity and capacitance (150 F g-1), whereas BP2000/MoS2 reached 110 F g-1 at a current load of 0.2 A g-1. The composites were also employed in a two-electrode cell equipped with an additional reference electrode to monitor the potential range of both electrodes during voltage extension. It has been shown that the active edge sites of MoS2 catalyze the hydrogen evolution, what limits the EC operational voltage below 1V.