Electrochemistry of Manganese in the Hydrophilic N-Butyl-N-methylpyrrolidinium Dicyanamide Room-Temperature Ionic Liquid

Abstract

The electrochemistry of manganese was studied at a polycrystalline platinum disk electrode in the hydrophilic ionic liquid N-butyl-N-methylpyrrolidinium dicyanamide ͑BMP-DCA͒. The density and absolute viscosity of BMP-DCA were determined over a temperature range from 299.0 to 343.0 K. A polynomial equation describing the temperature dependence of the density is provided. The viscosity obeys the Arrhenius temperature dependence. The dicyanamide anion exhibits a good complexing ability toward transition metal ions, and, therefore, Mn͑II͒ species can be introduced into the ionic liquid either by anodic dissolution of a manganese electrode or by dissolution of manganese ͑II͒ chloride. Cyclic voltammograms indicated that the electrodeposition of Mn from Mn͑II͒ was preceded by an overpotential-driven nucleation process. When the potential scan was reversed, the anodic stripping wave was fairly smaller than the cathodic wave, indicating that the oxidation of the Mn electrodeposits was kinetically hindered. However, this behavior was less noticeable for massive Mn electrodeposits. Manganese coatings were prepared at copper substrates by controlled-potential electrodeposition and characterized by scanning electron microscope, energy-dispersive spectrometer ͑EDS͒, and powder X-ray diffraction spectrometer ͑XRD͒. EDS analysis indicated that the purity of the Mn electrodeposits was good, although no crystal signal of Mn was observed in the XRD patterns.

New Frontiers in Materials Science Opened by Ionic Liquids

“…This is because most air-stable ILs show a large electrochemical window and negligible vapor pressure. Sub-micrometer to micrometer-ordered deposits of pure metals and semiconductors, such as Li, [143][144][145][146][147] Na, [147] K, [146,147] Cs, [148][149][150] Sr, [149] Mg, [151][152][153][154] Mn, [155][156][157][158][159] Ti, [160,161] Ta, [162,163] La, [164] Se, [165] In, [165] Ge, [166][167][168] and Si [169][170][171][172][173][174][175] have been electrodeposited in IL systems. In particular, Si deposition shows great promise for the development of novel technological process.…”

Underpotential Deposition of Silver on Au(111) from an Air‐ and Water‐Stable Ionic Liquid Visualized by In‐Situ STM

“…The [BMP][DCA] IL was chosen due to its relatively low viscosity, which is preferable for metal deposition. Estimated dynamic viscosity η of [BMP][DCA] under standard conditions was 50 mPa s . For comparison, the viscosity of other common organic ILs is considerably higher: η =110 mPa s for [BMIm][BF 4 ], where BMIm is 1‐butyl‐3‐methylimidazolium; η =78 mPa s for [BMP][TFSI], where TFSI is bis(trifluoromethylsulfonyl)imide; η =828 mPa s for the choline chloride/urea (1 : 2 mole ratio) DES …”

Effect of gluconate ions on electroreduction phenomena during manganese deposition on glassy carbon in acidic chloride and sulfate solutions

“…SO 3 2À , SeO 3 2À TeO 3 2À or SCN À ions are reduced on the cathode producing adsorbates acting as a poison for hydrogen evolution [1,[4][5][6][7][8]. Alternative organic additives (amines, paraformaldehyde, glycerol) [7] or non-aqueous solutions [9,10] as well as various electrolysis performances (pre-electrolysis, membrane reactor) [11,12] were also tested for the improvement of the process. It has to be noted that results of the electrochemical studies on the manganese deposition vary for different authors due to use solutions of different composition and purity or changed plating conditions.…”

“…Cu, Ni, Co, Zn, etc. [1,13] and organic compounds [7] stabilize c-Mn, VIB elements compounds enhance a-Mn formation [1,3], while amorphous deposits are obtained in the ionic liquids [9,10]. Crystal structure of manganese deposits is affected also by the substrate material (e.g.…”