Redox and transport behaviors of Cu(I) ions in TMHA-Tf2N ionic liquid solution

Abstract

The redox and transport behavior of monovalent copper species in an ammonium imide-type ionic liquid, trimethyln-hexylammonium bis((trifluoromethyl)sulfonyl)amide (TMHA-Tf 2 N) were examined with a micro-disc electrode to clarify its applicability to, for example, electroplating. It was found that the diffusion coefficient of Cu(I) ions in TMHA-Tf 2 N containing 12 mmol dm )3 Cu(I) ions was 1.2 Â 10 )6 cm 2 s )1 and the redox potential of Cu(I)/Cu was in the potential range 0.1-0.2 V vs. I ) /I 3 ) at 50°C. The diffusion coefficient was one order smaller than that of Cu(II) ions in aqueous solution due to the high viscosity of the ionic liquid. The diffusion coefficient of Cu(I) ion increased with rising temperature and was 1.0 Â 10 )5 cm 2 s )1 at 112°C, which was comparable to that of Cu(II) ions in aqueous CuSO 4 solutions at ambient temperature. This is accounted for by the drastic decrease in the viscosity of the ionic liquid solution with increasing temperature. The activation energy of diffusion was estimated to be 39 kJ mol )1 in the ionic liquid solution.

Carbon monoxide reactive separation with basic 1-hexyl-3-methylimidazolium chlorocuprate(I) ionic liquid: Electrochemical determination of mass transport properties

“…-2.1 V vs. Ag/AgCl, which is consistent with the cathodic limit of imidazolium-based cations [25,27], i.e., at that potential the imidazolium cation loses the C-2 proton and is reduced to a neutral radical [28,29]. 3.0 x 10 -7 cm 2 s -1 in trimethyl-n-hexylammonium bis(trifluoromethylsulfonyl)imide at 303 K [13] and 2.3 x 10 -7 cm 2 s -1 in 1-ethyl-3-methylimidazolium tetrafluoroburate at 303 K [14].…”

“…In this respect, several studies have determined the electrochemical behaviour and estimated the transport properties of transition metals in different ionic liquids as well as their mixtures with organic solvents for different purposes, e.g. use as coating material of copper [13][14][15][16][17][18] and chromium [19], the recovery of palladium from spent nuclear fuel [20] or electrowinning of rare earth metals [21], usually from cyclic voltammetry data, but also applying other electrochemical techniques such as chronoamperometry, chronopotentiometry and impedance spectroscopy.…”

Over 95% of large-scale length uniformity in template-assisted electrodeposited nanowires by subzero-temperature electrodeposition

“…The diffusion rate can be determined by the Fick's first law of diffusion where it is expressed as j = - D Δ C where j is the diffusion rate, D is the diffusion coefficient, and C is the local concentration. As the temperature is decreased, the diffusion coefficient of the Cu cations is also decreased since it follows the Arrhenius plot [26,27]. Moreover, not only the diffusion coefficient is decreased but also the thickness of the diffusion layer is elongated as the deposition temperature is decreased [28,29] since the nanoscale pore channels having aspect ratio up to 300:1 show a diffusion limited transport behavior [25].…”

Potentiostatic Cu-Zn Alloying for Polymer Metallization Using Medium-Low Temperature Ionic Liquid Baths

“…Thermodynamics and growth mechanism.-To gain thermodynamic insight into the dependence of the alloying potentials on the formation of intermetallic phases, the thermodynamically stable phase for a given electrode potential was calculated as we previously reported for Cu-Sn alloying with IL baths at 130-150 • C. [5][6][7][8] Here, we used literature data of Gibbs energy of formation 21…”

“…E > 0 mV vs Zn 2+ /Zn 0 , D418 Journal of The Electrochemical Society, 160 (9) D417-D421 (2013) to ensure the selective formation of Cu-Zn alloys where the activity of zinc a Zn is less than unity, as is the case for Cu-Sn alloying. [5][6][7][8] The alloying bath was set to be 150 • C and agitated at approximately 300 rpm using a magnetic stirring unit.…”