| Full text | |
| Author(s): |
Vicentini, Rafael
[1]
;
Venancio, Raissa
[1]
;
Nunes, Willian
[1]
;
Da Silva, Leonardo Morais
[2]
;
Zanin, Hudson
[1]
Total Authors: 5
|
| Affiliation: | [1] Univ Estadual Campinas, Sch Elect & Comp Engn, Carbon Sci Tech Labs & Mfg Grp, Ctr Innovat New Energies, Adv Energy Storage Div, BR-13083852 Campinas, SP - Brazil
[2] Fed Univ Jequitinhonha & Mucuris Valley, Dept Chem, Lab Fundamental & Appl Electrochem, BR-39100000 Diamantina, MG - Brazil
Total Affiliations: 2
|
| Document type: | Journal article |
| Source: | ACS APPLIED MATERIALS & INTERFACES; v. 13, n. 51 DEC 2021. |
| Web of Science Citations: | 0 |
| Abstract | |
Comprehensive electrochemical and operando Raman studies are performed to investigate the electrochemical stability window (ESW) of supercapacitors filled with normal (salt-in-water) and highly concentrated (water-in-salt, WiSE electrolytes. Impedance and chronoamperometric experiments are employed and combined with cyclic voltammetry to correctly define the ESW for a WiSE-based device. The total absence of water-splitting resulted in phase angles close to -90 degrees in the impedance data. It is verified that a 17 m NaClO4 electrolyte avoids the water-splitting up to 1.8 V. Furthermore, Raman studies under dynamic and static polarization conditions corroborate the existence of a solvent blocking interface (SBI), which inhibits the occurrence of watersplitting. Also, the reversible nature of the charge-storage process is assessed as a function of the applied voltage. At extreme polarization, the SBI structure is disrupted, thus allowing the occurrence of water-splitting and anionic (ClO4-) intercalation between the graphene sheets. (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: | 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 |