Gold electrochemistry in the acidic choline chloride-oxalic acid deep eutectic solvent

被引：2

作者：

Soma, Fousseni ^{[1
,2
]}

Nguyen, Trang Van ^{[1
,3
]}

Bougouma, Moussa ^{[2
]}

Djorf, Oussama ^{[1
]}

Buess-Herman, Claudine ^{[1
]}

Doneux, Thomas ^{[1
]}

机构：

[1] Univ libre Bruxelles ULB, Fac Sci, Chem Surfaces Interfaces & Nanomat ChemSIN, Blvd Triomphe,2,CP 255, B-1050 Brussels, Belgium

[2] Univ Norbert ZONGO, UFR Sci & Technol ST, Lab Chim Analyt, Phys Spatiale & Energet LCAPSE, Ave Maurice Yameogo,BP 376, Koudougou, Burkina Faso

[3] Vietnam Acad Sci & Technol, Inst Trop Technol, 18 Hoang Quoc Viet, Hanoi, Vietnam

来源：

ELECTROCHIMICA ACTA | 2024年 / 498卷

关键词：

Disproportionation; Comproportionation; Chronopotentiometry; Gold leaching; EQCM; GLASSY-CARBON; IONIC LIQUIDS; ELECTRODEPOSITION; SPECIATION; GRAPHITE;

D O I：

10.1016/j.electacta.2024.144660

中图分类号：

O646 [电化学、电解、磁化学];

学科分类号：

081704 ;

摘要：

The electrochemistry of the Au(III)-Au(I)-Au(0) system was studied in the choline chloride- oxalic acid dihydrate deep eutectic solvent at 60 degrees C. At glassy carbon electrodes, the 2 e (-) waves of the Au(III)/Au(I) and the 1 e (-) waves of the Au(I)/Au(0) are well separated in the cyclic voltammograms, whereas at platinum electrodes two anodic peaks but only one single 3 e (-) cathodic peak are observed. Electrochemical quartz crystal microbalance and zero-current chronopotentiometric experiments demonstrate the occurrence of a comproportionation reaction AuCl4- + 2Au(0) + 2Cl(-) reversible arrow 3AuCl (2) (-) when gold is electrodeposited from an Au(III) solutions. The standard potentials of the Au(III)/Au(I), Au(I)/Au(0) and Au(III)/Au(0) couples were estimated, and even though E A(u ( III ) / Au ( I )) (0)< E (0)(Au ( I ) / Au ( 0 )) translates into an equilibrium constant of the reaction being unfavourable to the comproportionation ( K (c,comp) < 1), it is shown that the reaction can be quantitatively displaced to the right under nonequilibrium conditions imposed by mass-transport.

引用

页数：9