In Situ Fast Construction of Ni₃S₄/FeS Catalysts on 3D Foam Structure Achieving Stable Large‐Current‐Density Water Oxidation

Abstract

By increasing the content of Ni3+, the catalytic activity of nickel‐based catalysts for the oxygen evolution reaction (OER), which is still problematic with current synthesis routes, can be increased. Herein, a Ni3+‐rich of Ni3S4/FeS on FeNi Foam (Ni3S4/FeS@FNF) via anodic electrodeposition to direct obtain high valence metal ions for OER catalyst is presented. XPS showed that the introduction of Fe not only further increased the Ni3+ concentration in Ni3S4/FeS to 95.02%, but also inhibited the dissolution of NiOOH by up to seven times. Furthermore, the OER kinetics is enhanced by the combination of the inner Ni3S4/FeS heterostructures and the electrochemically induced surface layers of oxides/hydroxides. Ni3S4/FeS@FNF shows the most excellent OER activity with a low Tafel slope of 11.2 mV dec−1 and overpotentials of 196 and 445 mV at current densities of 10 and 1400 mA cm−2, respectively. Furthermore, the Ni3S4/FeS@FNF catalyst can be operated stably at 1500 mA cm−2 for 200 h without significant performance degradation. In conclusion, this work has significantly increased the high activity Ni3+ content in nickel‐based OER electrocatalysts through an anodic electrodeposition strategy. The preparation process is time‐saving and mature, which is expected to be applied in large‐scale industrialization.

Sustainedly High‐Rate Electroreduction of CO2 to Multi‐Carbon Products on Nickel Oxygenate/Copper Interfacial Catalysts

“…The Ni 2p 3/2 peaks at the binding energies of 856.4 and 855.2 eV are attributed to Ni (III) and Ni(II), respectively (Figure 1f). [14] The average valence state of Ni is 2.7+, indicating that NiOOH was only slightly reduced in the NiOOH/Cu electrocatalyst. The Cu 2p 3/2 peak at a binding energy of 932.28 eV is attributed to Cu (0), supporting the existence of metallic Cu (Figure 1g).…”

Defect Engineering in Sn-Doped NiS/Ni3S2 Nanostructures for Oxygen Evolution Reaction

“…49,50 In contrast, after the addition of Sn ion, the peak value of Ni moves to Ni x S y /NF lower energy state (the Ni 2+ shows a negative shift of 0.37 eV), which changes the chemical binding state of Ni atoms in Sn−Ni x S y /NF-T, which may be the cause of lattice defects. 51,52 The Sn 3d state, which includes Sn 3d 3/2 and Sn 3d 5/2 , may be deconvoluted into two peaks, respectively. 53 In the S 2p spectrum, the binding energy of Sn−Ni x S y /NF-T at 162.2 and 163.4 eV corresponds to the characteristics of 2p 3/2 and 2p 1/2 of Ni−S, respectively.…”

“…The spectra of all samples are calibrated by the C 1s peak, which is located at 284.8 eV. For the Ni 2p spectrum, the binding energy at about 852.9 and 870.2 eV is assigned to Ni 0 , which is due to the supported NF structure. ,, Further peaks at 855.2 and 873.1 eV are assigned to Ni 2+ , while peaks at 856.5 and 874.4 eV are assigned to Ni 3+ (Ni 2p 3/2 and Ni 2p 1/2 , respectively), with a set of Ni shakeup satellites also being observed at higher binding energies (861.4 and 879.8 eV, respectively). , In contrast, after the addition of Sn ion, the peak value of Ni moves to Ni x S y /NF lower energy state (the Ni 2+ shows a negative shift of 0.37 eV), which changes the chemical binding state of Ni atoms in Sn–Ni x S y /NF-T, which may be the cause of lattice defects. , …”

Carbonized Wood Plate Decorated with a N-Doped Carbon Nanomushroom Encapsulating FeNiS2/(Co, Ni, Fe)9S8 Heteroparticle for Efficiently Catalyzing Oxygen Evolution Reaction

“…Transition-metal-based materials such as oxides, sulfides, phosphides, alloys, and hydroxides have been in the spotlight recently in the field of OER catalysis. Specially, the transition metal sulfides (TMSs, e.g., CoS x , NiS x , and FeS x ) hold a great promise owing to their abundant resources and favorable kinetics. The metal and sulfur element on the TMS surface can serve as a proton and hydride acceptor site, respectively, leading to a moderate bonding energy with the reaction intermediate during OER .…”