Boosting Activity and Stability of Electrodeposited Amorphous Ce‐Doped NiFe‐Based Catalyst for Electrochemical Water Oxidation

Abstract

NiFe-based hydroxides are considered as promising nonprecious catalysts for water oxidation due to their low cost and easy preparation. However, the rational design of NiFe-based electrocatalysts remains a great challenge to address the sluggish reaction kinetics and severe deactivation problems for oxygen evolution reaction (OER). Here, the authors report a facile approach to fabricate an amorphous Ce-doped NiFe hydroxide catalyst, which enables high activity and outstanding stability toward OER in alkaline media. The overpotential of electrodeposited amorphous Ce-doped NiFe is only 195 mV at 10 mA cm −2 . Meanwhile, the durability of the amorphous Ce-doped NiFe is maintained for 300 h at 100 mA cm −2 . The comprehensive characterization results reveal that the improved electrochemical performance of the amorphous Ce-doped NiFe catalyst is originated from the favorable oxidation transition of active sites enabled by Ce-doping. It is a very good strategy to introduce highly oxidized state ions to regulate the NiFe-based catalyst to improve the catalytic activity and stability.

Modulating crystal and electronic structure of NiFe-MOFs by inorganic acid for highly efficient electrochemical water oxidation

“…38,55 Based on the above investigation, we conclude that NiFe-MOF-2/NF has been transformed to Ni/Fe (oxy)hydroxide, which is considered the real active site for OER. This similar phenomenon is also observed in LDH, 56 metal sulfides, 57 selenides, 58 nitrides, 59 phosphides, 60 alloys 51 and other MOFbased electrocatalysts. 15,18,35 Based on the above characterization and OER results, the remarkable OER activity and superior stability of NiFe-MOF-2/NF can be attributed to the following merits.…”

Effective electronic tuning of Pt single atomsviaheterogeneous atomic coordination of (Co,Ni)(OH)2for efficient hydrogen evolution

“…32,65,66 The "fluctuation behavior" of the LSV was due to relatively large streams of bubbles being generated at the very large current density, which regularly interrupt the mass transfer process, leading to the evident fluctuation of the polarization curve. Furthermore, an appropriate and widely used frequency range of low (0.01 Hz) to high (100 K Hz) frequency was applied for the HER impedance measurements in this study 67,68 . Pt 1 /(Co,Ni)(OH) 2 /C demonstrated the smallest charge transfer resistance, which proves the optimized electronic transfer and enhanced intrinsic activity for the HER (Fig.…”

Universal Synthesized Strategy for Amorphous Pd‐Based Nanosheets Boosting Ambient Ammonia Electrosynthesis

“…[ 15 ] The amorphous features of the PdCoCu NSs were further confirmed by XRD spectra, which displayed typical amorphous features with broad diffuse peaks and no sharp crystalline phase diffraction peaks (Figure 1f). [ 16 ] These results indicate that the PdCoCu NSs are amorphous in the crystal structure. All elemental distribution of PdCoCu NSs was also characterized by magnified element mappings, where the Pd, Co, and Cu elements were distributed uniformly over the PdCoCu NSs (Figure 1g).…”