Deep Eutectic Solvent (DES) for In Situ Templating Carbon Material: Carbon Characterization and Application in Supercapacitors Containing Multivalent Ions
Nikola Zdolšek,
Bojan Janković,
Miloš Milović,
Snežana Brković,
Jugoslav Krstić,
Ivana Perović,
Milica Vujković
Affiliations
Nikola Zdolšek
Department of Physical Chemistry, “Vinča” Institute of Nuclear Sciences—National Institute of the Republic of Serbia, University of Belgrade, Mike Petrovića Alasa 12–14, 11351 Belgrade, Serbia
Bojan Janković
Department of Physical Chemistry, “Vinča” Institute of Nuclear Sciences—National Institute of the Republic of Serbia, University of Belgrade, Mike Petrovića Alasa 12–14, 11351 Belgrade, Serbia
Miloš Milović
Institute of Technical Sciences of SASA, Knez Mihailova 35, 11000 Belgrade, Serbia
Snežana Brković
Department of Physical Chemistry, “Vinča” Institute of Nuclear Sciences—National Institute of the Republic of Serbia, University of Belgrade, Mike Petrovića Alasa 12–14, 11351 Belgrade, Serbia
Jugoslav Krstić
Center for Catalysis and Chemical Engineering, Institute for Chemistry, Technology and Metallurgy, University of Belgrade, Njegoševa 12, 11000 Belgrade, Serbia
Ivana Perović
Department of Physical Chemistry, “Vinča” Institute of Nuclear Sciences—National Institute of the Republic of Serbia, University of Belgrade, Mike Petrovića Alasa 12–14, 11351 Belgrade, Serbia
Milica Vujković
Faculty of Physical Chemistry, University of Belgrade, Studentski Trg 12–14, 11158 Belgrade, Serbia
The development of carbon materials with desirable textures and new aqueous electrolytes is the key strategy to improve the performance of supercapacitors. Herein, a deep eutectic solvent (DES) was used for in situ templating of a carbon material. A carbon material was characterized (XRD, N2-physisorption, FTIR, SEM and EDS) and used as an electrode material for the first time in multivalent-based supercapacitors. In situ templating of carbon was performed using a novel DES, which serves as a precursor for carbon and for in situ generation of MgO. The generation of MgO and its roles in templating of carbon were discussed. Templating of carbon with MgO lead to an increase in surface area and a microporous texture. The obtained carbon was tested in multivalent-ion (Al3+ and Mg2+) electrolytes and compared with H2SO4. The charge-storage mechanism was investigated and elaborated. The highest specific capacitance was obtained for the Al(NO3)3 electrolyte, while the operating voltage follows the order: Mg(NO3)2 > Al(NO3)3 > H2SO4. Electrical double-layer capacitance (versus pseudocapacitance) was dominant in all investigated electrolytes. The larger operating voltage in multivalent electrolytes is a consequence of the lower fraction of free water, which suppresses hydrogen evolution (when compared with H2SO4). The GCD was experimentally performed on the Al(NO3)3 electrolyte, which showed good cyclic stability, with an energy density of 22.3 Wh kg−1 at 65 W kg−1.
