Electrochemical Cathodic Treatment of Mild Steel as a Host for Ni(OH)₂ Catalyst for Oxygen Evolution Reaction in Alkaline Media

Abstract

Oxygen evolution reaction (OER) catalysts and substrates play a vital role in the electrochemical water splitting process to generate chemical fuel and store renewable energy. The design and development of cost effective and efficient catalysts and substrates is still crucial and progressive towards the commercialization of water electrolyser. Herein, we have shown abundant mild steel (MS) as an efficient substrate as well as a catalyst host for OER by the cathodic treatment followed by the electrodeposited Ni(OH)2 at room temperature. The C MS Ni(OH)2 shows an overpotential (η) of 267 mV at a current density of 10 mA cm−2 with a Tafel slope of 66 mV dec−1, and affordable stability at the benchmark scale of 10 mA cm−2 current density operation for 10 h and harsh condition of 100 mA cm−2 current density for 50 h in the continuous electrolysis chronoamperometry test in 1 M KOH. The higher catalytic activity of C MS Ni(OH)2 compared to Ni(OH)2 electrodeposited on MS is due to the interaction of Fe(OH)2/FeOOH and Ni(OH)2/NiOOH. These results suggest a possible way to utilize MS substrates as catalyst and as a host for OER and other electrochemical applications in the future.

Modifying the 316L stainless steel surface by an electrodeposition technique: towards high-performance electrodes for alkaline water electrolysis

“…Hence, the formation of these species at lower potential on an electrode with Ni species refers to the ability of the electrode to catalyze the OER at lower overpotential and therefore the high catalytic activity of the electrode is expected. 72,99,100 Moreover, the charge under the oxidation peak can be used as an indicator for the electrochemical surface area (ECSA) determination as it refers to the charge density consumed for the above redox conversion. The ECSA of the as-prepared x NiP@SS and Ni@SS electrodes was calculated using the following formula: ECSA = Q / q , where Q is the charge of the anodic oxidation peak, which can be calculated by integrating the area under the oxidation peak of the CV curves depicted in Fig.…”

“…Incorporation of P into Ni on the surface of SS enhanced the catalytic activity of the modified SS towards both the HER and OER as well as for the overall water splitting. Additionally Maruthapandian et al 72 modified the mild steel (MS) with Ni(OH) 2 by a two-step cathodic treatment followed by electrodeposition to be used as an electrocatalyst for the OER. The electrochemical modification of the surface and the deposition of Ni(OH) 2 on MS (C MS Ni(OH) 2 ) resulted in a heterostructure of Fe(OH) 2 /FeOOH/Ni(OH) 2 which enhanced the catalytic activity toward the OER with overpotentials of 267 mV and 352 mV at 10 and 50 mA cm −2 current densities, respectively.…”

Electrocatalytic hydrogen evolution properties of anionic NiS 2 ‐Ni(OH) 2 nanosheets produced on the surface of nickel foam

“…This result corresponds to the C=O bond analysis of C 1 sd. When the binding energy is 529.8 eV, the O exists in the form of a Ni–O bond, further indicating the presence of Ni(OH) 2 in the material . As shown in Figure D, 162.3 eV and 163.6 eV are the peaks of S 2p 1/2 and S 2p 3/2 , respectively, showing that there is an S‐S bond in NiS 2 , and that the S exists in an S 2 2− valence state.…”

Template-Assisted Fabrication of ZnO/Co3O4 One-Dimensional Metal–Organic Framework Array Decorated with Amorphous Iron Oxide/Hydroxide Nanoparticles as an Efficient Electrocatalyst for the Oxygen Evolution Reaction

“…As seen from the inset in Figure F the catalytic current initially increased and then remained nearly constant for 30 h, indicating the high durability of the FeOOH @ MOF ZnO/Co 3 O 4 catalyst. The detailed performance of the present OER catalysts along with that of other recently reported Fe-doped and transition-metal materials and their derivatives are tabulated in Table S2. − Furthermore, to pursue the physical status of Co, Zn, and Fe and the structural features in FeOOH @ MOF ZnO/Co 3 O 4 , the catalyst was tested at a current density of 50 mA·cm –2 for an extended period (30 h), and the corresponding SEM post-tested images are depicted in Figure A,B. The images show that the rodlike morphology of MOF ZnO/Co 3 O 4 was retained and that FeOOH nanoparticles covered the nanorod surface.…”

“…In general, the OER process in an alkaline electrolyte involves various intermediates including M−OH, M−O, M−OOH, and M−O 2 , which are formed during the O 2 evolution reaction. The free energy levels of these intermediates and products decrease significantly after the incorporation of FeOOH, as a result of the electrocatalytic activity toward the OER process being enhanced predominantly 39,40. The catalytic active sites of the M(OH) 2 / MOOH domain effectively connect with Fe(OH) 2 / FeOOH during the OER in the anodic direction.…”