In this research in order to oxygen evolution reaction in the water-splitting process, inexpensive transition metal and multi-wall carbon nanotube are used. In the first part of this research, a multi-walled carbon nanotube nanocomposite incorporates cobalt oxide and molybdenum disulfide is used to modify the glassy carbon electrode by using an ultrasonic bath. FE-SEM, XRD, EDS, and elemental mapping techniques are used for electrocatalyst characterization. Afterward, the efficiency of electrocatalysts are investigated using linear sweep voltammetry, cyclic voltammetry, chronoamperometry, chronopotentiometry, and electrochemical impedance spectroscopy. In the linear sweep voltammetry technique, 290 mV overpotential in 2 M potassium hydroxide solution at 10 mA.cm-2 is obtained. Also, the activity of the prepared catalyst decreased by 10.81% after 200 cycles of voltammetry. In the Tafel plot, the slope for this catalyst is 81 mV.dec-1. In the second part of this research, nickel foam is modified as a catalytic substrate using double-shelled cobalt-iron layered-double hydroxide nanocage. FE-SEM, XRD, EDS, and elemental mapping techniques are used for electrocatalyst characterization. Afterward, the efficiency of electrocatalysts are investigated using linear sweep voltammetry, cyclic voltammetry, chronoamperometry, chronopotentiometry, and electrochemical impedance spectroscopy. In the linear sweep voltammetry technique, 260 mV overpotential in 3 M potassium hydroxide solution at 10 mA.cm-2 is obtained. In order to evaluate the stability of this catalyst by cyclic voltammetry, chronoamperometry method (at two potentials of 1.55 and 1.65 volts relative to the RHE), and chronopotentiometry method (at two current densities of 10 and 100 mA.cm2) are used. All stability tests are performed consecutively for 18 hours using one electrode. Catalyst stability increased after performing the mentioned methods. In the Tafel plot, the slope for this catalyst is 71.9 mV.dec-1.
