Electrodeposition of Bismuth in a Choline Chloride/Ethylene Glycol Deep Eutectic Solvent under Ambient Atmosphere

Abstract

The electrochemical behavior of bismuth(III) is investigated under ambient atmosphere in the ethaline deep eutectic solvent (DES) that is obtained by mixing 1 mol eq. of choline chloride and 2 mol eq. of ethylene glycol using Bi(NO 3 ) 3 as the Bi(III) source. Cyclic voltammetry indicates that the presence of water adsorbed from the atmosphere reduces the viscosity of the DES, and hence facilitates the reduction of Bi(III) to Bi. The presence of high water contents, however, suppresses the solubility of Bi(NO 3 ) 3 in the DES. Chronoamperometry experiments indicate that while the deposition of bismuth at a glassy carbon electrode involves with an overpotential-driven three dimensional instantaneous nucleation/growth process, the deposition of bismuth at the platinum, and nickel electrode involves with a progressive nucleation/growth. Crystalline bismuth films are deposited on Ni electrode by constant potential electrolysis. Scanning electron microscope images reveal that making the deposition potential more negative and/or increasing the temperature will reduce the deposited particle size. X-ray powder diffraction patterns suggest preferred orientation of the crystal growth. Bismuth coating can also be formed on copper substrate by galvanic displacement reaction between Bi(III) and Cu. Bismuth and its alloys are interesting chemicals largely used in various applications. For example, due to its unusual physical properties including electronic, thermoelectrical, and magneto-resistance, Bi is used for electrochromic and piezoelectric devices. Moreover, due to their catalytic properties and mechanical stability, bismuthmodified electrodes have been employed for electrochemical sensors in place of mercury electrodes. 1-3 Electrodeposition of Bi and its alloys has therefore attracted much attentions. Electrodeposition of Bi films with various morphologies and particles from micrometer to nanometer has been intensively studied in acid containing aqueous electrolytes without and with additives. 4-10 Electrodeposition of Bi has also been studied in organic 11 and molten salts. 12 Recently, ionic liquids (ILs) that are liquid at temperature below 100 • C have been considered more advantageous than organic electrolytes and high temperature molten salts because ILs are nonflammable, non-volatile, high thermal stability, and have a relatively good conductivity, as well as wide electrochemical window. 13 Consequently, ILs have been considered as electrolytes for electrochemical applications including electrodeposition. 14-16 Different types ILs have been developed including hydrophobic, and hydrophilic, and many of the traditional ILs are either moisture sensitive or expensive. More recently, Abbott and coworkers 17,18 have reported a new class of ILs known as deep eutectic solvents (DESs) which are mixtures of hydrogen bond donor such as quaternary ammonium salt like choline chloride and hydrogen bond acceptor such as urea or ethylene glycol. The DESs are non-toxic, low cost and stable against moisture compared to many know...

Toward a Circular Economy: Decontamination and Valorization of Postconsumer Waste Wood Using the ionoSolv Process

“…Glucan recovery for [H 1 Cim]­Cl-treated pulps was relatively higher and remained fairly constant with pretreatment compared to [DMBA]­[HSO 4 ]-treated pulps where glucan recovery dropped to 63% at 170 °C for 90 min, compared to 80% for [H 1 Cim]­Cl. However, it is important to note that glucan recovery of waste wood fines under the various conditions with approximately 25% glucan loss after 45 min pretreatment relative to 5–10% glucan loss was observed in previous ionoSolv studies using virgin untreated biomass. − It remains unclear why waste wood’s cellulose was more unstable during the pretreatment in this study, yet it might be related to the nature of the waste wood and the initial state of cellulose that made it more susceptible to degradation. However, it is still important to note that although the glucan loss was relatively high, it is still fairly reasonable given the heterogeneous nature of the feedstock and considering that part of this glucan loss may not be a degradation of cellulose but more of removal of the glucan contained in the hemicellulose in the form of galactoglucomannans and xyloglucans …”

“…Furthermore, we explore the possibility of recovering and reusing the IL in a cyclic manner by removing dissolved metal contaminants from the IL–stream via electrodeposition. The electrochemistry and electrodeposition of metals , and alloys , from IL systems have been studied extensively, but their behavior in mixed IL–water systems is seldom reported. To this end, the effect of water content on the electrochemistry and deposition morphology of Pb II , the dominant metal contaminant of waste wood fine, was investigated.…”

Targeted recovery of metals from thermoelectric generators (TEGs) using chloride brines and ultrasound

“…The CVs of Bi chloride in the various brines show two redox events, the first being related to the Bi 3+/0 couple (at around −0.6 V vs. [Fe(CN) 6 ] 3−/4− in CaCl 2 ·6H 2 O brines and around −0.4 V vs. [Fe(CN) 6 ] 3−/4− in ChCl brines) while the other is related to the formation of platinum–bismuth alloys, 41 and the subsequent oxidation of Bi from the alloy at more anodic potentials. 42 With increasing chloride concentration, the Bi 3+/0 redox couple becomes more cathodic, i.e. the Bi 3+ ion is stabilised relative to elemental Bi, meaning that Bi metal should be easier to oxidise.…”

Energy-Efficient and Green Extraction of Bismuth Metal in Methanesulfonic Acid-Based Membrane Electrochemical Systems

“…Bismuth electrodeposition could also be carried out in nitric acid, , sulfosalicylate, and deep eutectic solvents . Jiang et al produced metal bismuth with skeleton and strip-like shapes in a HNO 3 medium with the addition of EDTA.…”

“…Bismuth electrodeposition could also be carried out in nitric acid, 46,47 sulfosalicylate, 48 and deep eutectic solvents. 49 Jiang et al 46 produced metal bismuth with skeleton and strip-like shapes in a HNO 3 medium with the addition of EDTA. Rajamani et al 47 studied the effect of citric acid, poly(vinyl alcohol), and betaine on the morphology of bismuth in a Bi (0.01 mol/L)−HNO 3 (4 mol/L) solution.…”