Quasi‐Parallel NiFe Layered Double Hydroxide Nanosheet Arrays for Large‐Current‐Density Oxygen Evolution Electrocatalysis

Abstract

Designing advanced electrocatalysts for oxygen evolution at large current density (>500 mA cm−2) is critical to practical water splitting applications. Herein, a novel quasi‐parallel NiFe layered double hydroxide (NiFe LDH) nanosheet arrays with pattern alignment on Ni foam was developed. The initial α‐Ni(OH)2 layer induced effective coprecipitation between Ni2+ and Fe3+ for the formation of LDH phase, guaranteeing the electronic pulling effect among metal cations and enhancing the interaction between active materials and substrate for excellent adhesion and electrical conductivity. Quasi‐parallel NiFe LDH nanoarrays exhibited outstanding oxygen evolution activity with a small Tafel slope of 30.1 mV dec−1 and overpotentials of 196, 255, and 284 mV at a current density of 10, 500, and 1000 mA cm−2 in 1.0 m KOH solution, respectively, and high stability over 40 h at 750 mA cm−2. This work presents a new strategy towards fabricating electrode materials with exceptional performance.

Doping Mo into NiFe LDH/NiSe Heterostructure to Enhance Oxygen Evolution Activity by Synergistically Facilitating Electronic Modulation and Surface Reconstruction

“…[5] Ye et al prepared a novel quasi-parallel NiFe LDH nanosheet array to enhance the electronic traction effect among metal cations and the interaction between the active materials and substrate for excellent adhesion and conductivity, endowing the nanosheet with outstanding oxygen evolution activity and stability. [6] Beyond the control of crystallinity, heteroatom doping is an available strategy to modulate the electronic structure of electrocatalysts. Tang et al reported that the rich in-plane active sites can be generated by the lattice-confined Mo atoms to activate the basal plane of Mo-CoOOH with three-dimensional (3D) nanoframes, where the lattice-confined Mo sites in the two dimensional (2D) basal-plane are active sites for OER, which can bond moderately with the reaction intermediates and thereby enhance the activity.…”

“…Ye et al. prepared a novel quasi‐parallel NiFe LDH nanosheet array to enhance the electronic traction effect among metal cations and the interaction between the active materials and substrate for excellent adhesion and conductivity, endowing the nanosheet with outstanding oxygen evolution activity and stability [6] . Beyond the control of crystallinity, heteroatom doping is an available strategy to modulate the electronic structure of electrocatalysts.…”

Spherical Ni/Ni3Se2 Heterostructure for Efficient Electrochemical Oxidation Reactions

“…In addition, the Tafel results in Figure S4b show that the most active Ni/Ni 3 Se 2 sample has the smallest Tafel slope (114 mV dec À 1 ), indicating that the sample has fast kinetics during the OER process. [20] These results indicate that appropriate metallic nickel content can effectively improve the electrocatalytic performance of the nickel-nickel selenide composite.…”

“…Current density was calculated based on the geometric area of electrodes. At different scan rates (20,40,60,80,100, 120 and 140 mV s À 1 ), the capacitances of samples were obtained by CVs in the non-Faradaic potential region. The working electrode was prepared through a drop-casting method and the typical procedure was as follows: a catalyst ink was prepared by dispersing 4 mg of the sample powder in 1 mL of waterÀ ethanol solution at volume ratio of 2 : 1 containing 30 μL of Nafion solution.…”

Highly Sensitive and Selective Gas Sensors Based on NiO/MnO2@NiO Nanosheets to Detect Allyl Mercaptan Gas Released by Humans under Psychological Stress

“…The formation of the parallel layer is probably by the formation of tiny grooves when KMnO 4 corrodes Ni(OH) 2 . [ 43 ] The formation of such parallel sheets can expose more active edge sites, which could supply more adsorption and reactive sites to enhance the sensing performance. However, the thickness of the NiO nanosheets decreased to approximately 8.9 nm.…”