Electrodeposition of Indium from an Ionic Liquid Investigated by In Situ Electrochemical XPS

Abstract

The electrochemical behavior and electrodeposition of indium in an electrolyte composed of 0.1 mol/L InCl3 in 1-butyl-1-methylpyrrolidinium bis(trifluoromethylsulfonyl)amide ([Py1,4]TFSI) on a gold electrode were investigated. The cyclic voltammogram revealed several reduction and oxidation peaks, indicating a complex electrochemical behavior. In the cathodic regime, with the formation of an In-Au alloy, the reduction of In(III) to In(I) and of In(I) to In(0) takes place. In situ electrochemical X-ray photoelectron spectroscopy (XPS) was employed to investigate the reduction process by monitoring the oxidation states of the components during the cathodic polarization of 0.1 mol/L InCl3/[Py1,4]TFSI on a gold working electrode under ultra-high vacuum (UHV) conditions. The core electron binding energies of the IL components (C 1s, O 1s, F 1s, N 1s, and S 2p) shift almost linearly to more negative values as a function of the applied cell voltage. At −2.0 V versus Pt-quasi reference, In(I) was identified as the intermediate species during the reduction process. In the anodic regime, a strong increase in the pressure in the XPS chamber was recorded at a cell voltage of more than −0.5 V versus Pt quasi reference, which indicated, in addition to the oxidation reactions of In species, that the oxidation of Cl− occurs. Ex situ XPS and XRD results revealed the formation of metallic In and of an In-Au alloy.

Physical vapor deposition-free scalable high-efficiency electrical contacts to MoS2

“…The spectral decomposed XPS spectrum obtained for region-1 is shown in figure 1(b), while that for region-2 is shown in supplementary data S2. XPS spectra from both regions show two In 3d peaks (In 3d 5/2 and 3d 3/2 ) at energies of 444 eV and 451.5 eV, which correspond to those of metallic Indium, In(0) [54,55]. The splitting between the In 3d 5/2 and 3d 3/2 peaks is 7.54 eV, as expected for pure metallic Indium [54].…”

“…XPS spectra from both regions show two In 3d peaks (In 3d 5/2 and 3d 3/2 ) at energies of 444 eV and 451.5 eV, which correspond to those of metallic Indium, In(0) [54,55]. The splitting between the In 3d 5/2 and 3d 3/2 peaks is 7.54 eV, as expected for pure metallic Indium [54]. We do not observe any other resolvable peaks to validate the presence of any alloys of In and Au.…”

In situformation of a ZnS/In interphase for reversible Zn metal anodes at ultrahigh currents and capacities

“…30,33 Aer discharge, new peaks at 445.6 and 453.5 eV reect the generation of metallic In nanoparticles reduced in the discharging process. 34,35 Thus, the XRD and XPS results mentioned above conrm the formation of ZnS and metallic In aer discharge. It is noted that the in situ-developed ZnS and metallic In exhibit high chemical stability, ionic conductivity, mechanical strength and anti-corrosion.…”

Alloy/Perovskite Compounds Modified by Plasma Treatment and their Role in Enhancing the Capacitance of Sustainable Graphene Supercapacitors

“…[73,74] Additionally, the In3d orbital was analyzed for the GNMI/CNCCO electrode before its utilization in the SC and a band related to In 0 was observed at 443.5 eV, see Figure 10a. The XPS spectrum was again measured on the GNMI/CNCCO electrode used in the SC (In3d orbital) and this time, we detected an additional oxidation state of In 3 + at 446.6 eV, [75,76] see Figure 10b. Interestingly, the deconvoluted XPS spectrum for the Ni2p orbital (GNMI/CNCCO electrode not used in the SC) exhibited bands at 854.1, 856.6 and 861.7 eV, which are associated to Ni 0 , Ni 2 + and Ni 3 + [77,78] (see Figure 10c), respectively.…”