Codeposition of Nanocrystalline Co-Ni Catalyst Based on 1-ethyl-3-methylimidazolium Bisulfate and Ethylene Glycol System for Hydrogen Evolution Reaction

Abstract

The codeposition behavior of Co(II) and Ni(II) in 1-ethyl-3-methylimidazolium bisulfate ([EMIM]HSO 4 ) ionic liquid (IL) and ethylene glycol (EG) system is recorded using cyclic voltammetry (CV). The result indicates that the mechanism of Co-Ni codeposition is an anomalous codeposition, and both the inhibition for Ni(II) reduction and the anomalous codeposition phenomena can be improved by the increase of Co(II) concentration in the system. These Co-Ni deposits are characterized using EDS, XRD and SEM. SEM micrographs indicate that the surface morphology of Co-Ni deposits can be changed by the increase of Co content, and these deposits with many additional elongated acerose crystals, which are germinated on the spherical "nodules" surface, can be prepared. XRD pattern reveals the feature peak of crystalline Co 1.2 Ni 2.8 with a preferred orientation direction and the average size of grains is calculated to be about 14.6 nm. Moreover, the electrocatalytic activity for hydrogen evolution reaction (HER) on the prepared Co-Ni catalyst surface is investigated using linear sweep voltammetry (LSV) and electrochemical impedance spectra (EIS). These results indicate that the obtained catalyst presents an excellent electrocatalytic activity and durability for HER with an overpotential of 139 mV at 10 mA cm −2 in 1 M KOH solution.

A Tunable Triple-Band Near-Infrared Metamaterial Absorber Based on Au Nano-Cuboids Array

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Fabrication of SiOx-G/PAA-PANi/Graphene Composite With Special Cross-Doped Conductive Hydrogels as Anode Materials for Lithium Ion Batteries

“…The carbon contents of SiO x -G, SiO x -G/PAA-PANi, and SiO x -G/PAA-PANi/graphene were about 46.85, 55.22, and 56.08 wt%, respectively (Figure 5). The superficial passivation of SiO x lead to the oxidation of Si in air was not distinguished between 600 and 800 • C (Chen et al, 2014;He et al, 2019;. They are beneficial to improve the cycle performance of SiO to varying degrees.…”

Tunable Broadband Solar Energy Absorber Based on Monolayer Transition Metal Dichalcogenides Materials Using Au Nanocubes

“…This provides a very suitable method for optimizing the absorption in the visible wavelength region by altering the incident angle. As a result, the combination of polarization insensitivity and excellent absorption stability at oblique incidence makes this kind of absorber more feasible in the pragmatic application of solar energy absorption [65][66][67][68]. In order to explore the value of the absorber in practical application, the solar energy absorption response of the proposed structure was studied.…”