Nickel Confined in the Interlayer Region of Birnessite: an Active Electrocatalyst for Water Oxidation

Abstract

We report a synthetic method to enhance the electrocatalytic activity of birnessite for the oxygen evolution reaction (OER) by intercalating Ni(2+) ions into the interlayer region. Electrocatalytic studies showed that nickel (7.7 atomic %)-intercalated birnessite exhibits an overpotential (η) of 400 mV for OER at an anodic current of 10 mA cm(-2) . This η is significantly lower than the η values for birnessite (η≈700 mV) and the active OER catalyst β-Ni(OH)2 (η≈550 mV). Molecular dynamics simulations suggest that a competition among the interactions between the nickel cation, water, and birnessite promote redox chemistry in the spatially confined interlayer region.

Iron‐Doped Nickel Phosphide Nanosheets In Situ Grown on Nickel Submicrowires as Efficient Electrocatalysts for Oxygen Evolution Reaction

“…Typically,h igher Ta fel slopes ( % 120 mV dec À1 )a re associated with water adsorption on the catalytic site as the rate-determining step, whereas lower Ta fel slopes( % 40 mV dec À1 )s uggest OÀOb ond formation as the rate-determining step. [49] Therefore, both water adsorption and OÀOf ormation are ratedetermining step for (Ni 0.87 Fe 0.13 ) 2 P-Ni and RuO 2 in the high-potential region, [50] and might be influenced by the reactions in low-potential region, leading to the different Tafel slopes.…”

Insight into pH‐Dependent Formation of Manganese Oxide Phases in Electrodeposited Catalytic Films Probed by Soft X‐Ray Absorption Spectroscopy

“…Recent studies showed that disturbance of abirnessite structure by doping it with other 3d transitionm etals can enhance the catalytic activity of the material. [41][42][43] Such as tructural disturbancem ight also be reached by aj udicious choice of the parameters in the electrodeposition process. However,e xamination of the spatialphase distribution and/or structural distortions is beyond the capabilities of the specific experimental technique used herein-consequentlys uggesting ap romising area for future study.…”

From Enzymes to Functional Materials—Towards Activation of Small Molecules

“…031-0.061 s À1 )m aterials revealed highera ctivity for OER than birnessite (TOF = 0.0004 s À1 )u nder the same experimental conditions. [128][129][130] Based on the structural similarity of the compounds,i tw as suggestedt hat water oxidation mainly occurs in the interlayer region of the birnessite composites.…”