The Effect of Sulfuric Acid Concentration on the Physical and Electrochemical Properties of Vanadyl Solutions

Batteries

JamieS. Lawton¹  DanielJ. Donnelly²  ThomasM. Arruda²  SeanP. Flanagan²  SophiaM. Tiano² 

[1] Department of Chemistry and Biochemistry, University of Massachusetts Dartmouth, N. Dartmouth, MA 02747, USA;Department of Chemistry, Salve Regina University, Newport, RI 02840, USA;

关键词: vanadium redox flow batteries (VRFBs);    cyclic voltammetry;    electrochemical kinetics;    viscosity;    electron paramagnetic resonance;    diffusion coefficient;   

DOI  :  10.3390/batteries4030040

来源: DOAJ

【 摘 要 】

The effects of sulfuric acid concentration in VO2+ solutions were investigated via electrochemical methods and electron paramagnetic resonance. The viscosity of solutions containing 0.01 M VOSO4 in 0.1–7.0 M H2SO4 was measured. Diffusion coefficients were independently measured via electrochemical methods and electron paramagnetic resonance (EPR), with excellent agreement between the techniques employed and literature values. Analysis of cyclic voltammograms suggest the oxidation of VO2+ to VO2+ is quasi-reversible at high H2SO4 concentrations (>5 mol/L), and approaching irreversible at lower H2SO4 concentrations. Further analysis reveals a likely electrochemical/chemical (EC) mechanism where the H2SO4 facilitates the electrochemical step but hinders the chemical step. Fundamental insights of VO2+/H2SO4 solutions can lead to a more comprehensive understanding of the concentration effects in electrolyte solutions.

【 授权许可】

Unknown