Synthesis and characterization of the `Japanese rice-ball'-shaped Molybdenum Blue Na₄[Mo₂O₂(OH)₄(C₆H₄NO₂)₂]₂[Mo₁₂₀Ce₆O₃₆₆H₁₂(OH)₂(H₂O)₇₆]∼200H₂O

Abstract

The hybridized lanthanide-containing molybdenum blue (Ln-MB) wheel Na4[Mo2O2(OH)4(C6H4NO2)2]2[Mo120Ce6O366H12(OH)2(H2O)76]∼200H2O ({Mo2(C6H4NO2)2}2{Mo120Ce6}) was assembled in an aqueous one-pot synthesis. The Ln-MB was hybridized with 2-picolinic acid through the generation of the organometallic counter-ion [Mo2O2(OH)4(C6H4NO2)2]2+. Control experiments demonstrated that the position of the carboxylic acid group (2-position to the N atom) in the hybridization component is critical in yielding single crystals of Ln-MB. In addition to single-crystal X-ray diffraction (XRD) analysis, which revealed a `Japanese rice-ball'-shaped Ln-MB as the anion, elemental analyses, IR spectroscopy, and thermogravimetric analysis (TGA) were performed to confirm its structure and composition. Bond-valence-sum calculations (BVS) revealed that {Mo2(C6H4NO2)2}2{Mo120Ce6} is composed of a 24-electron reduced anionic ring, which was confirmed by Vis–NIR spectroscopy.

Solvent-modulated assembly of peptide and cerium functionalized gigantic {Mo120Ce6}2 dimers for high-efficiency photocatalytic oxidation

“…1). [43][44][45] Its basic framework comprises 12 {Mo 8 }, 6 {Mo 2 }, and 12 {Mo 1 } BBs along with 5 {Ce(H 2 O) 5 } and 1 {Ce(H 2 O) 4 } units (Fig. 1b).…”

“…[32][33][34][35][36][37][38][39][40][41] By introducing lanthanides (Ln) as structural modulators and heterometal functionalities, the size, charge, nuclearity, curvature and even chirality can be controlled for the resulting clusters. [42][43][44][45][46][47][48][49][50][51][52][53][54] This indeed promoted the generation of a variety of MB clusters ranging from {Mo 90 Ce 10 } to {Mo 150 La 2 } as well as dimeric {Mo 128 Eu 4 } 2 and {Mo 100 Ce 6 } 2 . [43][44][45][46][47][48][49][50][51][52][53][54] Besides, amino acids and peptides have recently emerged as ligands to build functional MB clusters.…”

“…[42][43][44][45][46][47][48][49][50][51][52][53][54] This indeed promoted the generation of a variety of MB clusters ranging from {Mo 90 Ce 10 } to {Mo 150 La 2 } as well as dimeric {Mo 128 Eu 4 } 2 and {Mo 100 Ce 6 } 2 . [43][44][45][46][47][48][49][50][51][52][53][54] Besides, amino acids and peptides have recently emerged as ligands to build functional MB clusters. 51,52,[55][56][57] They on one hand can functionalize the inner/outer surfaces with chiral groups and, on the other hand, behave as structure-directing agents to trap anion templates for cluster formation.…”