Enhanced Oxygen Evolution of a Magnetic Catalyst by Regulating Intrinsic Magnetism

Abstract

The promotion of magnetic field on catalytic performance has attracted extensive attention. However, little research has been reported on the performance of the oxygen evolution reaction (OER) for the modulating intrinsic magnetism of the catalyst under a magnetic field. Herein, we adjusted the intrinsic magnetism of the Co x Ni1–x Fe2O4-nanosheet by adjusting the ratio of Co and Ni, and researched the relationship between the OER activity and the intrinsic magnetism. The results indicate that the CoFe2O4-nanosheet has the most OER activity increases in the magnetic field due to the optimal intrinsic magnetism. The required overpotential of CoFe2O4-nanosheet@NF to reach a current density of 10 mA cm–2 was reduced by 21 mV under about 100 mT magnetic field compared with no magnetic field, and the degree of improvement of OER activity of different magnetic catalysts in the same magnetic field is positively correlated with the intrinsic magnetism of the catalyst. Therefore, magnetic field assistance provides a new, effective, and general strategy to improve the activity of electrodes for water splitting.

Open-Microcolumn Array: A Novel Approach for Enhanced Electrocatalytic Bubble Desorption in Microreactors

“…As shown in Figure S10, the characteristic diffraction peaks of CoOOH-NR@NCA, Co 4 NiOOH-NR@NCA, and Co 4 FeOOH-NR@NCA were observed in the spectrum of Co 4 Fe 0.5 Ni 0.5 OOH-NR@NCA, indicating the successful preparation of the trimetallic (oxy)­hydroxides catalyst. , XPS was employed to reveal the chemical environment of the elements associated with the introduction of multiple components. As can be seen from Figure S11, the survey spectra indicated that Ni, Co, Fe, O, and C elements appeared, confirming that all relevant elements were successfully introduced into the preprepared catalysts Figure a displays high-resolution XPS spectra of Co 2p, where the split peaks correspond to Co 2p 3/2 and Co 2p 1/2 orbitals, respectively.…”

“…The TEM image (Figure S7) confirmed a consistent diameter of around 50 nm for the individual NR. The high-resolution transmission electron microscopy (HRTEM) image (Figure e) of the Co 4 Fe 0.5 Ni 0.5 OOH-NRs exhibits a smooth and crystalline surface, with a lattice spacing of 2.59 Å, corresponding to the (102) crystal planes . Chemical composition analysis through inductively coupled plasma optical emission spectrometry (ICP-OES, Table S1) and energy-dispersive X-ray spectroscopy (EDS, Figure S8) confirmed that the molar ratio of Co/Fe/Ni remained roughly at 4:0.5:0.5.…”

“…The high-resolution transmission electron microscopy (HRTEM) image (Figure 1e) of the Co 4 Fe 0.5 Ni 0.5 OOH-NRs exhibits a smooth and crystalline surface, with a lattice spacing of 2.59 Å, corresponding to the (102) crystal planes. 35 Chemical composition analysis through inductively coupled plasma optical emission spectrometry (ICP-OES, Table S1) and energy-dispersive X-ray spectroscopy (EDS, Figure S8) confirmed that the molar ratio of Co/Fe/Ni remained roughly at 4:0.5:0.5. Elemental mapping (Figure S9) revealed a uniform distribution of Fe, Co, and Ni throughout the Co 4 Fe 0.5 Ni 0.5 OOH-NR@NCA region.…”

“…As can be seen from Figure S11, the survey spectra indicated that Ni, Co, Fe, O, and C elements appeared, confirming that all relevant elements were successfully introduced into the preprepared catalysts. 35 at. %).…”

Recent Development of External Magnetic Field Assisted Oxygen Evolution Reaction‐A Mini Review

“… Scatter plot of magnetic field intensity and overpotential reduction efficiency of DC magnetic field. ( Remarks a: CoFe 2 O 4 ‐nanosheet@NF‐Magnetic, [38] b: NiFe‐LDH‐Magnetic, [11] c: Ni−S−CoFe2O4/NF‐Magnetic, [37] d: FeCO 2 O4‐Magnetic, [29] e: magnetic catalytic nanocages, [32] f: NiCoFe‐LDHS‐Magnetic, [27] g: 2D FM Cr2Te3 nanosheets‐Magnetic, [22] h: Cu 1 −Ni 6 Fe 2 ‐LDH [39] …”