Three Lanthanide-Functionalized Antimonotungstate Clusters with a {Sb4O4Ln3(H2O)8} Core: Syntheses, Structures, and Properties.

Three lanthanide (Ln)-functionalized antimonotungstate (AT) clusters with a {Sb4O4Ln3(H2O)8} core [H2N(CH3)2]14Na8H16[Sb4O4Ln3(H2O)8W2O4(H2O)2(B-α-SbW9O33)4]2·87H2O [Ln = Dy3+ (1), Ho3+ (2), Y3+ (3)] were synthesized in an acidic aqueous solution. Their molecular structural unit comprises two {Sb4O4Ln3(H2O)8}-core-incorporated tetrameric [Sb4O4Ln3(H2O)8W2O4(H2O)2 (B-α-SbW9O33)4]19- polyanionic units, each of which is assembled from an unprecedented [Sb4O4Ln3(H2O)8W2O4(H2O)2]17+ heteroatom cluster surrounded by four trivacant [B-α-SbW9O33]9- subunits. What is noteworthy is that a tetrahedral {Sb4O4} cluster is located at the center of the polyanionic unit, as far as we know, which is very infrequent in multi-Ln-functionalized polyoxometalate chemistry. Solid-state luminescent properties and energy migration of AT ligands to Dy3+ and Ho3+ cations in 1 and 2 have been intensively probed at ambient temperature. By varying the exciting wavelength from 250 to 450 nm, the emitting color could vary from blue to yellow for 1 and blue to green-yellow for 2, separately. In addition, high catalytic activities and good reusability of 2 as a heterogeneous catalyst for oxygenation reaction of sulfides have been systematically performed.