An Unusual Bismuth–Antimony–Europium Cluster-Imbedded Polyoxotungstate and Its Bidirectional Luminescence Detection

Abstract

124H 2 O (1) was prepared. The polyoxoanion skeleton of 1 contains a Krebstype polyoxotungstate [W 4 O 10 ][B-β-BiW 9 O 33 ] 2 } 14− ({Bi 2 W 22 }) (1a) as a linker that offers six active coordinate O atoms (two μ 3 -O and four μ 2 -O atoms) to grasp two Bi−Sb−Eu cluster-imbedded tungsten-oxo clusters {[Bi 5.35 Sb 0.65 Eu 3 O 9 (H 2 O) 9 ][B-α-SbW 9 O 33 ] 3 } 18− (1b) through Bi−O−W and Sb−O−W bonds. 1b comprises an unprecedented nonanuclearity Bi−Sb−Eu [Bi 5.35 Sb 0.65 Eu 3 O 9 (H 2 O) 9 ] 9+ cluster encircled by three trivacant [B-α-SbW 9 O 33 ] 9− segments in a triangular motif through Eu−O−W, Sb−O−W, and Bi−O−W linkages into a trilobal trimer.Moreover, a bidirectional detection method by using 1 as an effective luminescence probe was proposed to recognize both Mn 2+ and CO 3 2− through an "on−off−on" mode. 1 can be used as an "on−off" luminescent sensor to detect Mn 2+ ions in aqueous solution. The limit of detection was 0.05 μM (9 × 10 −6 mg L −1 ), which is much lower than the World Health Organization (WHO) guideline for Mn 2+ concentration in drinking water (0.05 mg L −1 ). Then the Mn 2+ -quenching system can be used as an "off−on" sensor to detect CO 3 2− in water system. This work provides a new research idea for the application of rare-earth-imbedded polyoxotungstate-based materials in the field of optical smart detection.

Recent advances in lanthanide-based POMs for photoluminescent applications

“…62 Recently, they prepared an unprecedented Eu-POM aggregate as a bidirectional detection probe to continuously recognize both Mn 2+ (on–off) and CO 3 2− (off–on), succinctly summarized as an “on–off–on” mode. 98…”

{SeO2(OH)} Bridging Lanthanide-Containing Antimono-Seleno-Tungstates

“…Each trimeric subunit is established by 1 SbW 9 O 33 ({SbW 9 }), 1 SeW 9 O 33 ({SeW 9 }), and 1 Se 1/2 Sb 1/2 W 9 O 33 ({Se 1/2 Sb 1/2 W 9 }) fragments encapsulating a hexanuclear Ln-W-oxo cluster Ln 2 W 4 O 9 (H 2 O) 4 ({Ln 2 W 4 }). In contrast to the widely reported POMs constructed by a single species of lacunary fragment, the aggregates containing the lacunary POMs with different heteroatoms are exceedingly rare. ,− To the best of our knowledge, 1 – 4 are the first POM clusters that contain different types of trivacant Keggin fragments ({SbW 9 }, {SeW 9 }, and {Se 1/2 Sb 1/2 W 9 }) and simultaneously exist μ 2 -{SeO 2 (OH)} as bridging groups to achieve the integration of the whole molecular structure. In addition, studies on the catalytic properties indicated that compound 3 , as a heterogeneous catalyst, is capable of the selective catalytic oxidation of various sulfides and sulfur mustard simulant 2-chloroethyl ethyl sulfide (CEES) in the presence of the environmentally friendly oxidant H 2 O 2 .…”

A two-dimensional cadmium-based metal–organic framework as an excellent probe: highly selective luminescent “turn on” detection of tetrahydrofuran and quantitative analysis of water

“…14,15 Among them, the luminescent MOFs can be used to detect different types of analytes because of the highly effective and contactless luminescent tests. 7,16,17 MOFs surpass other common chemosensor materials because of their highly flexible architectures and fascinating chemical properties. 18 However, the works on the detection of THF are less reported.…”