Facile Preparation of Three-Dimensionally Ordered Macroporous Alumina, Iron Oxide, Chromium Oxide, Manganese Oxide, and Their Mixed-Metal Oxides with High Porosity

Abstract

This paper describes a facile method to produce three-dimensionally ordered macroporous (3DOM) alumina, iron oxide, manganese oxide, chromium oxide, and their mixed-metal oxides. An ethylene glycol (EG)-methanol mixed solution of metal nitrates was infiltrated into the void of the colloidal crystal template of a monodispersed poly(methyl methacrylate) (PMMA) sphere. Heating initiated nitrate oxidation of the EG to produce metal glyoxylate salt. Further heating converted the glyoxylate salt to metal oxide and decomposed PMMA which produced the desired 3DOM metal oxides. Two important parameters of this method are clarified in order to produce a well-ordered 3DOM structure in high yield: (1) The nitrate oxidation temperature should be lower than the glass transition temperature of the PMMA. ( 2) The heat produced by oxidative decomposition of the PMMA should effectively be removed. Furthermore, high porosity (66-81%) of the 3DOM materials was confirmed by Hg porosimetry, which can permit facile transport of guest molecules and particles in potential catalysis and filtration.

Triethylene Glycol Stabilized CoFe2O4 Nanoparticles

“…2a and 2b reveal that the vibration band of C-O bond shifts from 1113 cm −1 for pure TREG to 1103 cm −1 for the current CoFe 2 O 4 nanocrystals which indicates that the oxygen atom of C-O bond coordinates with the metal [7,13,[20][21][22][23][24][25][26]. Figure 3 shows the TGA and differential thermogram (DTG) curves for synthesized CoFe 2 O 4 nanoparticles via polyol method with TREG.…”

Facile synthesis of three-dimensionally ordered macroporous LaFeO3-supported gold nanoparticle catalysts with high catalytic activity and stability for soot combustion

“…Three-dimensionally ordered macroporous (3DOM) materials have become a focus research topic due to their potential applications, such as catalysts, photonic crystals, chemical sensors and absorbents [20][21][22]. Because of their periodic features with uniform big pore size (>50 nm), 3DOM materials would enhance the catalytic activity by providing more reaction active sites on accessibly macroporous wall surfaces, and by permitting high flow-through capability within a low-density structure.…”

Three-dimensionally ordered macroporous La0.6Sr0.4MnO3 with high surface areas: Active catalysts for the combustion of methane

“…The colloidal crystal template is fabricated by ordering monodispersed microspheres (e.g., polystyrene (PS), poly(methyl methacrylate) (PMMA), or silica) into a face-centered close-packed array [19]. With PS microbeads as template, Sadakane et al [20][21][22] fabricated 3DOM La 1Àx Sr x FeO 3 (x = 0-0.4) with a surface area of 24-49 m 2 /g.…”