Diffusion Coefficients of Cuprous and Cupric Ions in Electrolytes with High Concentrations of Bromide Ions

Abstract

This study examines the diffusion coefficients of cuprous and cupric ions in aqueous solutions containing 4–6 mol·dm–3 bromide ion. Under these conditions, the majority of the Cu2+ species is the complex CuBr4 –2, and the majority of Cu+ species is the complex CuBr3 –2. Diffusion coefficients were obtained for temperatures ranging from 298 to 334 K via a rotating disk electrode and the Levich relationship. Diffusion coefficients for the cuprous bromide complex were found to be between 11.9 and 19.1 × 10–6 cm2·s–1. Diffusion coefficients for the cupric bromide complex ranged between 4.5 and 12.0 × 10–6 cm2·s–1. Confidence intervals were calculated with reasonable uncertainties. The diffusion coefficients were found to be in good agreement with literature values of cuprous and cupric chloride complexes.

Kinetics of Cu2+ Reduction and Nanoparticle Nucleation at Micro‐scale 1,2‐Dichlorobenzene‐water Interface Studied by Cyclic Voltammetry and Square‐wave Voltammetry

“…However, it is unlikely that this error could amount to the current growth of the magnitude experienced in the measurements. The diffusion coefficients of Cu 2+ and Cu + were approximated as equal, which is not entirely true, and different values for them have been obtained for different systems, and the diffusion coefficient for Cu + is often slightly larger than that of Cu 2+ [47,48]. Therefore, the assumption of equal diffusion coefficients may have lead to some error in the simulations.…”

Review—Flow Batteries from 1879 to 2022 and Beyond

“…[7][8][9] As a faculty member at CWRU in the 1980's, Prof. Savinell was involved in the development of H 2 -Br 2 flow batteries. [10][11][12][13] In more recent years his work expanded 14 to all-iron (Fe-Fe 3+ ), [15][16][17][18][19][20][21][22][23] all -copper 24,25 and zinc-iron 26 hybrid flow batteries, as well as to all-vanadium, [27][28][29][30][31] organic ambipolar 32 and microemulsion 33 RFBs.…”

Copper Chloro-Complexes Concentrated Solutions: An Electrochemical Study

“…Specifically, their solubility and diffusion coefficients are of paramount importance in these systems. Copper bromo-and chloro-complexes have been investigated and the thermodynamic and kinetics parameters evaluated from dilute and concentrated copper solutions [22][23][24][25][26][27][28][29]. Stability constants were also evaluated in dilute solutions of copper chloride complexes [25].…”

“…Stability constants were also evaluated in dilute solutions of copper chloride complexes [25]. It was found that in the presence of a high concentration of halides, Cu + and Cu 2+ form halide-complexes with increasing halide content by increasing the number of halide ligands, up to CuX 3 2− and CuX 4 2− in complexes for Cu(I) and Cu(II), respectively [25,26]. The diffusion coefficients of Cu + and Cu 2+ range from 10 −5 to 10 −6 cm 2 s −1 , with higher values for higher temperatures and for Cu + than for Cu 2+ , with a small variation for different X − concentration [26].…”