Isolation of Blackberry-Shaped Nanoparticles of a Giant {Mo₇₂Fe₃₀} Cluster and Their Transformation to a Crystalline Nanoferric Molybdate

Abstract

When an aqueous solution of sodium molybdate is added to an aqueous solution of ferric chloride, acidified with acetic acid, a giant {MoFe} cluster is instantaneously formed as the amorphous substance Na[MoFeO(CHCOO)(OH)(HO)]·180 HO (1). Compound 1 consists of aggregated nanovesicles of {MoFe} clusters, as confirmed by field-emission scanning electron microscopy and transmission electron microscopy images of 1. An aqueous suspension of 1 upon moderate heating results in the formation of crystalline nanoferric molybdate, which gives insight into understanding the formation of a yellow coating mineral, ferrimolybdite, frequently found on the ores of molybdenum.

{Mo72Fe30} Nanoclusters for the Visible-Light-Driven Photocatalytic Degradation of Organic Dyes

“…It can be deprotonated to [Mo 72 Fe 30 O 252 (CH 3 COO) 4 (OH) 16 (H 2 O) 108 ] 2– instantaneously, which aggregate to nanoblackberries in the form of amorphous clusters. Agglomeration of these nanoparticles has resulted in the formation of a macroporous nanomaterial having open pores on the surface . Whereas, substitution of 30 dinuclear [Mo V 2 O 4 (CH 3 COO)] + linkers in {Mo 132 } by 30 Fe 3+ aq centers furnishes rhombohedral crystals of {Mo 72 Fe 30 } as discrete capsules which slowly dissolves in water (cluster 1).…”

“…The nanostructured capsules are cross-linked to a monoclinic structure by keeping them in acidic NaCl solution for 1 week and then condensed to an orthorhombic structure as a layer compound after drying for some hours in air . Nevertheless, amorphous {Mo 72 Fe 30 } clusters can be precipitated immediately by mixing of concentrated solutions of iron­(III) and molybdenum salts. , This important characteristic could extend the scope of catalytic application. More important is the lack of toxicity of {Mo 72 Fe 30 } nanoclusters in warm blooded animals, which is a notable feature for a nanomaterial from a safety point of view.…”

Carbon Nanotube Synthesis Using Fe‐Mo/MgO Catalyst with Different Ratios of CH4 and H2 Gases

“…During the measurement, the specimen was changing that could be related with decomposition of the molecules under electron beam. Since the size of the {Fe 30 Mo 72 } core is 2.5 nm, the observed spots are likely the metal clusters obtained from individual molecules or their agglomerates, which are readily formed in aqueous solutions . Disintegration of the {Fe 30 Mo 72 } cores under the heat treatment was confirmed by TEM images of the {Fe 30 Mo 72 }/MgO powder calcined in air at 700 °C (Figure b).…”

A nanoscopic icosahedral {Mo72Fe30} cluster catalyzes the aerobic synthesis of benzimidazoles

“…S8 and S17 †) may be reasonable for this exhibition. 30 Furthermore, greater disorders in the structure of amorphous materials providing more unsaturated sites for adsorption of molecules onto the solid surface, increase their catalytic activity. 31,32 It should be noted that, metal-oxide {Mo 9 O 9 } pores resulting from structural organization of the pentagons and linkers in Keplerates provides access to the capsule's interior just for very small molecules.…”

“…This result along with the lack of 1,2-disubstituted benzimidazole products are reasonable to suggest an oxidative mechanism for this reaction under catalytic inuence of {Mo 72 Fe 30 } as presented in Scheme 2. 33 Deprotonation of water molecules ligated to Fe III centers in the amorphous cluster generating 16OH À groups, 30 facilitates the inner sphere interaction of the metal ion with oxygenic species, 34 which accelerates the oxidative aromatization process at nal step of reaction.…”