Fundamentals and Implication of Point of Zero Charge (PZC) Determination for Activated Carbons in Aqueous Electrolytes.

Autor: Slesinska S; Poznan University of Technology, Institute of Chemistry and Technical Electrochemistry, Berdychowo 4, Poznan, 60965, Poland., Galek P; Poznan University of Technology, Institute of Chemistry and Technical Electrochemistry, Berdychowo 4, Poznan, 60965, Poland., Menzel J; Poznan University of Technology, Institute of Chemistry and Technical Electrochemistry, Berdychowo 4, Poznan, 60965, Poland., Donne SW; Discipline of Chemistry, University of Newcastle, Callaghan, New South Wales, 2308, Australia., Fic K; Poznan University of Technology, Institute of Chemistry and Technical Electrochemistry, Berdychowo 4, Poznan, 60965, Poland., Płatek-Mielczarek A; Poznan University of Technology, Institute of Chemistry and Technical Electrochemistry, Berdychowo 4, Poznan, 60965, Poland.; Laboratory for Multiphase Thermofluidics and Surface Nanoengineering, Department of Mechanical and Process Engineering, ETH Zurich, Sonneggstrasse 3, Zurich, 8092, Switzerland.; Unbound Potential GmbH, Bönirainstrasse 14, Thalwil, 8800, Switzerland.
Jazyk: angličtina
Zdroj: Advanced science (Weinheim, Baden-Wurttemberg, Germany) [Adv Sci (Weinh)] 2024 Nov 13, pp. e2409162. Date of Electronic Publication: 2024 Nov 13.
DOI: 10.1002/advs.202409162
Abstrakt: The point of zero charge (PZC) is a crucial parameter for investigating the charge storage mechanisms in energy storage systems at the molecular level. This paper presents findings from three different electrochemical techniques, compared for the first time: cyclic voltammetry (CV), staircase potentio electrochemical impedance spectroscopy (SPEIS), and step potential electrochemical spectroscopy (SPECS), for two activated carbons (ACs) with 0.1 mol L -1 aqueous solution of LiNO 3 , Li 2 SO 4 , and KI. The charging process of AC operating in aqueous electrolytes appears as a complex phenomenon - all ionic species take an active part in electric double-layer formation and the ion-mixing zone covers a wide potential region. Therefore, the so-called PZC should not be considered as an absolute one-point potential value, but rather as a range of zero charge (RZC). SPECS technique is found to be a universal and fast method for determining RZC, as applied here together with the EQCM. In most cases, the RZC covers a potential range from ≈100 to ≈200 mV and the correlation of the range with the carbon microtexture is clear, highlighting the role of the ion-sieving effect. It is postulated that PZC for porous materials in aqueous electrolytic solutions should be considered instead as RZC.
(© 2024 The Author(s). Advanced Science published by Wiley‐VCH GmbH.)
Databáze: MEDLINE
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