Nanostructured Ni–Co alloy electrodes for both hydrogen and oxygen evolution reaction in alkaline electrolyzer

Bimetallic Co-Based (CoM, M = Mo, Fe, Mn) Coatings for High-Efficiency Water Splitting

“…The Volmer step represents electrosorption of the hydrogen proton (H + ) to form the surface adsorbed hydrogen atom (MH ads ) on the active metal sites (M), the Heyrovsky step is the electrochemical desorption of MH ads to form H 2 , and the Tafel step represents recombination of two MH ads on the metal surface to form H 2 [ 32 , 33 ]. Tafel slope values suggest that HER at CoMn, Co, and CoFe proceeds by the Volmer–Heyrovsky mechanism where the electrochemical desorption of the MH ads is the rate-limiting step [ 32 , 34 ], while during HER at Ni and CoMo, the Volmer step, i.e., electrochemical sorption of H + , represents the rate-determining step. It could be seen that the determined Tafel slope values deviated from the theoretical ones toward higher values that might have been caused by the formation of surface oxides of lower conductivity compared to the metallic surface [ 34 ].…”

“…Tafel slope values suggest that HER at CoMn, Co, and CoFe proceeds by the Volmer–Heyrovsky mechanism where the electrochemical desorption of the MH ads is the rate-limiting step [ 32 , 34 ], while during HER at Ni and CoMo, the Volmer step, i.e., electrochemical sorption of H + , represents the rate-determining step. It could be seen that the determined Tafel slope values deviated from the theoretical ones toward higher values that might have been caused by the formation of surface oxides of lower conductivity compared to the metallic surface [ 34 ].…”

“…Ni–Co nanowires with ca. 95% of Co and 5% of Ni showed the highest HER and OER activity with a low potential of –0.231 V and 1.494 V required to attain a current density of 10 mA·cm −2 for HER and OER, respectively [ 34 ].…”

Production of NF / NiCo /Ag catalyst for hydrogen generation in alkaline medium

“…While hydrogen gas is not a direct fuel, it has special properties that make it an excellent energy carrier 13‐15 . There are several methods for hydrogen production, but water electrolysis is the most convenient way that can generate the highest purity of hydrogen, although the method is expensive 16‐18 . The key drawback of electrolysis is the high energy needed for the hydrogen formation reaction.…”

“…[13][14][15] There are several methods for hydrogen production, but water electrolysis is the most convenient way that can generate the highest purity of hydrogen, although the method is expensive. [16][17][18] The key drawback of electrolysis is the high energy needed for the hydrogen formation reaction. The effective solution may be the following: Electricity prices can be decreased by solar energy, which is inexpensive, profitable, and sustainable.…”