| Full text | |
| Author(s): |
Venancio, Raissa
;
Vicentini, Rafael
;
Costa, Lenon H.
;
Teofilo, Reinaldo
;
Da Silva, Leonardo M.
;
Zanin, Hudson
Total Authors: 6
|
| Document type: | Journal article |
| Source: | JOURNAL OF ENERGY STORAGE; v. 50, p. 12-pg., 2022-06-01. |
| Abstract | |
The analyzes of micro-, meso- and macro-porous carbon electrodes in a symmetrical supercapacitor filled with a 1.0 M TEABF(4) EC-DMC electrolyte were reported in this work. The activated carbon (AC), multi-walled carbon nanotubes, and graphite materials were studied. The results indicate AC is the best electrode material for the application with high specific capacitance and energy. The Raman operando analyzes of AC show that the D- and G- bands shift their positions and intensities. The cause of this phenomenon is the electrostatic ionic adsorption inside very narrow pores, affecting the vibrational mode and the work function of the material, resulting in the shift of the Fermi level of the material. For mesoporous carbon, this phenomenon is much less pronounced. In principle, graphite has enough specific capacitance for competitive application. However, its overall surface area is reduced. Graphite's Raman operando analyzes revealed the BF4- insertion into graphene layers. The G-band splits while the in-situ electrochemical data support a capacitance with three orders of magnitude higher than expected for a purely electrostatic adsorption process on graphite. Overall, this fundamental study evidences that in-situ electrochemistry and Raman spectroscopy combined could offer important information on the energy storage process for supercapacitors. (AU) | |
| FAPESP's process: | 14/02163-7 - Development of supercapacitors devices from graphene, carbon nanotubes and diamonds |
| Grantee: | Hudson Giovani Zanin |
| Support Opportunities: | Research Grants - Young Investigators Grants |
| FAPESP's process: | 20/14968-0 - Electrodes and electrolytes characterization under dynamic conditions: analysis of evolved gases in different cell assemblies and abuse conditions |
| Grantee: | Raissa Venâncio |
| Support Opportunities: | Scholarships in Brazil - Master |
| FAPESP's process: | 17/11958-1 - CINE - Advanced Energy Storage Division |
| Grantee: | Rubens Maciel Filho |
| Support Opportunities: | Research Grants - Research Centers in Engineering Program |
| FAPESP's process: | 18/20756-6 - Pseudocapacitors from metal oxides and activated carbon composites |
| Grantee: | Willian Gonçalves Nunes |
| Support Opportunities: | Scholarships in Brazil - Doctorate |