Polymer‐Assisted Direct and Rapid Microwave Synthesis of Mesoporous Binary and Ternary Metal Oxides for Electrocatalytic Water Oxidation

A novel quick and facile polymer-assisted microwave synthesis route to prepare mesoporous binary metal oxides α-Fe₂O₃ and α-Mn₂O₃ and spinel-type ferrites NiFe₂O₄ and ZnFe₂O₄ is presented, which can potentially be applied for many other mixed metal oxides. The presented synthesis only needs 15-30 min, much shorter than conventional approaches for mesoporous materials. Thorough characterization of the materials is performed by Powder X-Ray Diffraction (PXRD), Raman spectroscopy, energy dispersive X-ray spectroscopy (EDXS), nitrogen physisorption analysis, mercury intrusion porosimetry (MIP), diffuse reflectance infrared fourier transform (DRIFT) spectroscopy, UV-Vis-spectroscopy, X-Ray photoelectron spectroscopy (XPS), and scanning (SEM) as well as transmission electron microscopy (TEM) and selected area electron diffraction (SAED). Furthermore, mesoporous α-Mn₂O₃ and NiFe₂O₄ are applied as electrocatalysts for electrocatalytic oxygen evolution in alkaline media, showing improved performance compared to nanoparticles or EISA-derived mesoporous NiFe₂O₄.