On the electrochemical formation of nickel nanoparticles onto glassy carbon from a deep eutectic solvent

Influence of water content and applied potential on the electrodeposition of Ni coatings from deep eutectic solvents

“…In all cases, j-t transients have the same characteristic regions as these reported in many potentiostatic electrodeposition experiments, also from DESs [23,25,37,49]. The first interval consists of a monotonically decaying current which is followed by a stable, almost zero current period of time, which ranges from 1.5 s for E ¼ À1:10V to 170 s for E ¼ À 0:70V.…”

Water distribution at the electrified interface of deep eutectic solvents

“…[4][5][6]9,10 Due to these compelling unusual physicochemical properties, DESs have been increasingly used in a vast number of applications with success, including solvent extraction, 11,12 biodiesel production, 13 organic synthesis, 5,10,14,15 lubrication, 5 nanoporous carbon synthesis, 16,17 fuel treatment, 10,11,18 gas capture [19][20][21] and DNA stabilization. 22,23 Besides, they have also been extensively used as solvents for many electrochemical purposes such as electrodeposition, [24][25][26][27][28][29] energy conversion, 30 energy storage, [31][32][33][34] etc. 4,31,35,36 Extensive experimental and computational studies have been dedicated to rationalize the correlation between melting point depression and the hydrogen bond strength and its inuence on the thermo-physical properties of DESs, with special emphasis on 1 : 2 choline chloride-urea (Reline).…”

“…39 On the other hand, more recently, it has been shown that the presence of small amounts of residual or intentionally added water in Reline could be benecial for controlling the size, shape and distribution of deposited nanoparticles. 5,24,26,29,49,51,52 Also, in a carbon dioxide gas capture experiment, it has been shown that the solubility of carbon dioxide in a mixed water-Reline solvent is strongly dependent on the amount of water, and that increasing the amount of water leads to a decrease in carbon dioxide solubility. 37 Despite a number of studies of bulk water-DES mixtures, the effect of residual water on the electried interface in DESs has not been studied yet.…”

“…7,8,24,49,54 In contrast, if water molecules accumulate close to the electrode surface, at high electrode surface polarization, electrolysis of water can take place, producing hydroxide ions (OH À ) and hydrogen gas (H 2 ) at the cathode and oxygen (O 2 ) at the anode. 26,29 The presence of OH À , generated by water splitting, at the electrode-electrolyte interface could lead to the chemical breakdown of DESs, 26,29,55 which compromises the electrochemical potential window. Recently, this has been conrmed experimentally using combined electrochemical and surface analysis techniques.…”

On the Control and Effect of Water Content during the Electrodeposition of Ni Nanostructures from Deep Eutectic Solvents

“…14,15 For these reasons, the number of publications on electrodeposition from DES is spectacularly increasing, notably for nickel. [16][17][18][19][20][21][22][23][24][25][26][27][28][29][30][31][32][33][34] The electrodeposition from these non-aqueous baths have proven successful to obtain nickel coatings, [18][19][20]34 nickel-based alloys 21,22,24,25,27,28,35 and nanostructured nickel films for corrosion resistance. 29,30 Similarly, DES were also used for the synthesis of a multitude of nanostructures (Pd, 36 Au, 37 ...), due to the capability of these solvents to slow down the electrochemical processes, thus, having a better control of the deposition of nanostructures.…”