Controlled Synthesis of Hierarchical Nanostructured Metal Ferrite Microspheres for Enhanced Electrocatalytic Oxygen Evolution Reaction

Abstract

Ferrite MFe2O4 (M = Ni, Co, etc.) metal oxides have been the focus of intense research, studied as promising electrocatalysts due to their good catalytic activity and stability for oxygen evolution reaction (OER). Structure engineering is a significant solution to achieve a high catalytic performance; further, optimizing the structure and specific surface area (SSA) of metal ferrite (CoFe2O4 and NiFe2O4) is regarded as a good choice. Herein, we designed hierarchical porous nanostructured CoFe2O4 and NiFe2O4 microspheres with the assistance of sodium dodecyl sulfonate by solvothermal and annealing methods. We found that three-dimensional microspheres assembled by nanoparticles and porous nanosheets exhibit higher SSAs for NiFe2O4 (158.47 m2 g–1) and CoFe2O4 (144.52 m2 g–1). Their higher SSA is much higher than those of other CoFe2O4-based and NiFe2O4-based materials. The as-prepared metal ferrite microspheres exhibit excellent OER electrocatalytic activity with lower Tafel slopes (55.2 and 58.2 mV dec–1) and lower overpotentials (235 and 280 mV) at a constant current density of 10 mA cm–2 and long-term stability, which is better than that of NiFe2O4 and CoFe2O4 bulks. This method for preparing a large SSA is expected to be applied in other spinel metal oxides.

Urea Electrooxidation in Alkaline Environment: Fundamentals and Applications

“…10–11). Ferrite was modified with tetraethoxysilane to create materials suitable for Urs immobilization [39] . Electrochemical biosensors demonstrated a marked contribution to urea response in comparison to traditional electrochemical sensors due to the high selectivity and good performance they offer (Figure 6B).…”

“…Ferrite was modified with tetraethoxysilane to create materials suitable for Urs immobilization. [39] Electrochemical biosensors demonstrated a marked contribution to urea response in comparison to traditional electrochemical sensors due to the high selectivity and good performance they offer (Figure 6B). However, the limitations of enzymatic sensors still persist, and the development of stable urea biosensors to accommodate multi-scenario applications appear essential.…”

Enhanced Electrochemical Sensing of Butylated Hydroxy Anisole through Hollow Metal–Organic Frameworks with Gold Nanoparticles and Enzymes

“…Electronic states and chemical compositions of HRP@HZIF-Au nanocomposites were investigated by XPS analyses, which provided the additional evidence of the existence of Au NPs on the surface of HZIF-8 (Figure A). , Typical Au 4f-Zn 3p displayed a shoulder on the side with low binding energy (Figure B). Four separate peaks including Au 4f 7/2 (83.82 eV), Au 4f 5/2 (87.86 eV), Zn 3p 3/2 (89.33 eV), and Zn 3p 1/2 (91.33 eV) were obtained .…”

Surfactant-Assisted rGO-PbO2 Electrode to Boost Acrylamide Degradation in Industrial Sewage

“…Due to the strong hydrophobicity of the prepared electrode, the generated ·OH is basically distributed in the solution near the electrode, thus oxidizing the pollutant. Moreover, the larger the hydrophobic angle, the stronger the catalytic ability of redox. , If a large amount of ·OH is attracted to the electrode interface, it would not only cause oxidation to the electrode but also increase the adverse reaction of oxygen evolution and reduce the catalytic performance of the electrode. Therefore, compared to the PbO 2 electrode, the highly hydrophobic PbO 2 electrode has higher catalytic efficiency and longer service life.…”