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

How charge regulation and ion-surface affinity affect the differential capacitance of an electrical double layer

Full text
Quadre, Amanda B. [1] ; de Carvalho, Sidney J. [1] ; Bossa, Guilherme Volpe [1]
Total Authors: 3
[1] Sao Paulo State Univ UNESP, Dept Phys, Inst Biosci Humanities & Exact Sci, BR-15054000 Sao Jose Do Rio Preto, SP - Brazil
Total Affiliations: 1
Document type: Journal article
Source: Physical Chemistry Chemical Physics; v. 22, n. 32, p. 18229-18238, AUG 28 2020.
Web of Science Citations: 0

The differential capacitance of an electrical double layer is a topic of great importance to develop more efficient and environment-friendly energy storage devices: electric double layer supercapacitors. In addition to the bare electrostatic interactions, recent experimental and computational studies suggest that electrodes covered by ionizable groups do interact selectively with specific ion types, an effect that can increase the maximal conductivity and voltage of a supercapacitor. Inspired by this, in the present work we investigate how ion-specific non-electrostatic interactions modify the differential capacitance of a flat electrode whose surface is covered by ionizable groups subject to a charge regulation process. The incorporation of hydration interactions by means of ion-specific Yukawa potential into the Poisson-Boltzmann theory allows our model to describe different scenarios of ion-surface affinity and, hence, the selective depletion or accumulation of specific ion types close to a charged surface. We obtained larger capacitance values when considering electrodes that favor the accumulation of cations and the depletion of anions. (AU)

FAPESP's process: 17/21772-2 - Extensions of the Poisson-Boltzmann Theory to the study of the differential capacitance of an electrical double layer
Grantee:Guilherme Volpe Bossa
Support type: Scholarships in Brazil - Post-Doctorate
FAPESP's process: 18/22382-6 - The role of charge regulation and non- electrostatic interactions on the differential capacitance of supercapacitors
Grantee:Amanda Beatriz Quadre
Support type: Scholarships in Brazil - Scientific Initiation
FAPESP's process: 18/01841-2 - Computational Simulation Studies on the Interaction Between Polyelectrolytes and Macromolecules
Grantee:Sidney Jurado de Carvalho
Support type: Regular Research Grants