Biologic sp 150

The electrical properties of the MoS₂/AIP electrode were characterized using Hall measurements (HL5500PC, Accent optical technology, US). The optical properties of the thin film electrodes were measured using UV/Visible spectrometer (V-670, Jasco), US. The surface morphology MoS₂/AIP electrode was analyzed using FE-SEM, Hitachi, Japan (field-emission scanning electron microscope). Crystal structure and chemical composition of samples were examined using XRD (x-ray diffraction), Rigaku, Japan and XPS (x-ray photoelectron spectroscopy), Thermo Fisher, US. The electrochemical behavior of electrodes was evaluated using Bio Logic SP-150, Bio Logic, France instrument. For the three-electrode measurements, Ag/AgCl and Pt wires were used as reference and counter electrodes, respectively. 3 M KOH aqueous solution was used as an electrolyte.

Charge-discharge operation at constant current was set for CDI at different influent initial concentrations. This procedure immediately followed electrosorption-desorption at constant voltage for each level of concentration. Five different charging currents were used: 1, 0.5, 0.25, 0.125, and 0.1 A·g⁻¹. The discharge current was maintained at −1 A·g⁻¹, which aims to obtain an increasing charging-discharging time ratio. The performance was assessed based on the retention in charging time of the charging current for 5 cycles and the chronocoulometric or charge pattern on the electrode surface. Furthermore, to see the effect of repeated charge/discharge, a charging-discharging run was conducted with 100 ppm NaCl for 100 cycles with each cycle containing five different charging currents previously stated.
The CDI module was connected to a potentiostat/galvanostat (BioLogic SP-150, Seyssinet-Pariset, France) that was used to control all the voltage and current. The maximum of the instrument in measuring all electrochemical parameters is only up to 0.1% of the full scale range. Flowrate was set at 25 mL·min⁻¹ for all CDI operations. This instrument was connected to EC-Lab V10.40 software (Seyssinet-Pariset, France) that recorded all the data such as current, voltage, charge, and power consumption with respect to time.

The electrochemical study was conducted employing the Bio-logic SP-150 workstation was purchased from Seyssinet Pariset, France. A slurry of the working substance was carefully produced employing a MgO, MgO/CNT and Ni-MgO/CNT catalyst, activated carbon and polyvinylidene fluoride (PVDF) in 85:10:5 ratios, respectively. Manual mixing was performed in a few drops of N-methyl pyrrolidinone (NMP). Also, 3 mg of catalyst was loaded to each electrode for the electrochemical investigations. Ni substrate was subjected to precleaning with 1 M HCl in 100 mL of deionized (DI) water employing ultrasonication for 30 min, effectively removing the NiOx surface layer. For the electrochemical studies, the catalyst-coated Ni foam (1 × 1 cm²) served as the working electrode, Pt wire as the counter electrode and the Ag/AgCl electrode functioned as the reference electrode in a 3-electrode system specifically for HER applications.