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(Reference retrieved automatically from Web of Science through information on FAPESP grant and its corresponding number as mentioned in the publication by the authors.)

ew Insights on the Sodium Water-in-Salt Electrolyte and Carbon Electrode Interface from Electrochemistry and Operando Raman Studie

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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