Assembly of Cerium(III)‐Stabilized Polyoxotungstate Nanoclusters with SeO₃²⁻/TeO₃²⁻ Templates: From Single Polyoxoanions to Inorganic Hollow Spheres in Dilute Solution

Abstract

A versatile one-pot strategy was employed to synthesize three cerium(III)-stabilized polyoxotungstates nanoclusters by combining cerium linkers and SeO3(2-)/TeO3(2-) heteroanion templates: K32Na16[{(XO3)W10O34}8{Ce8(H2O)20}(WO2)4(W4O12)]·nH2O [X=Se, n=81 (1); X=Te, n=114 (2)] and K12Na22[{(SeO3)W10O34}8{Ce8(H2O)20}(WO2)4{(W4O6)Ce4(H2O)14(SeO3)4(NO3)2}]· 79H2O (3), which are the first lanthanide-containing polyoxotungstates with selenium or tellurium heteroatoms. The three clusters were characterized by single-crystal X-ray structure analysis, IR spectroscopy, thermogravimetric/differential thermal analysis, UV/Vis spectroscopy, ESI-MS, and X-ray photoelectron spectroscopy. Their electrochemical, photoluminescence, and magnetic properties were investigated. Their behavior in solution was studied by transmission electron microscopy, which showed that their single polyoxoanions assemble into intact, uniform-sized, purely inorganic hollow spheres in dilute water/acetone solution.

Unprecedented Selenium and Lanthanide Simultaneously Bridging Selenotungstate Aggregates Stabilized by Four Tetra‐vacant Dawson‐like {Se2W14} Units

“…In the past few decades, there have been numerous reports on "pure" STsa nd the metal functionalization of STsb yT M, (CH 3 ) 2 Sn 2 + ,a nd Ln cations, [3][4][5][6][7][8][9][10][11][12][13][14] however,l ittle work has been devotedt ot he organic-inorganic composites with selenium and Ln simultaneously bridging LnCST aggregates.A saresult, the elaborate design andp reparation of novel triangular pyramidal {SeO 3 }b ridgingL nCST aggregates remains ah uge challenge. The difficulties in manufacturing {SeO 3 }b ridging LnCST aggregates lie in two factors:( i) as is well known to us, the direct combination of oxyphilic Ln ions with oxygen-rich lacunary ST fragments easily leads to amorphous precipitates instead of crystallization;( ii)LnCSTf ragments often have highly negativelyc harged surfaces, which meanst he introductiono f negativelyc harged {SeO 3 }g roups becomes more difficult.…”

“…[2] Selenotungstates (STs) as an important subfamily of POMs that have attracted increasing interest in the past decadeb ecause of the enormous diversity of structures and potentiala pplications.The past decade has witnessed great research developments in STs, including "pure"S Ts andd ifferent metals [such as transition metal (TM), (CH 3 ) 2 Sn 2 + ,a nd Ln] functionalized STs (Table S1 in the Supporting Information). [3][4][5][6][7][8][9][10][11][12][13][14] Some novel nanosized "pure" ST clusters and TM-substituted STsw ere discovered by Cronin andc o-workersi nc onventionala cidic aqueous solution. [3][4][5][6][7] Kalininae tal.…”

“…Amongt he reported LnCSTs ,t he Ce 3 + -incorporated STs are the most common. [13, 14] To the besto fo ur knowledge,t here is no report of selenium and Ln simultaneouslyb ridging LnCST aggregates although numerous TM-, organotin-, and Ln-encapsulated STsa nd "pure" STsh ave been already obtained. This research background attracts ouri nteresta nd provides us an excellent opportunity to exploret his field.…”

Lanthanide-Connecting and Lone-Electron-Pair Active Trigonal-Pyramidal-AsO3 Inducing Nanosized Poly(polyoxotungstate) Aggregates and Their Anticancer Activities

“…Each {W 4 Eu} segment consists of a semilunar {W 4 } group with a supporting Eu III cation, in which two edging-sharing {W 2 } moieties are integrated by sharing an oxygen atom and a Eu III cation. This semilunar {W 4 } group is entirely distinct from the rhombic {W 4 } group in [enH 2 ] 2 [Ni(H 2 O) 4 ] 2 [Ni(en) 2 ] 2 [Ni(en)] 2 {[(α- AsW 6 O 26 )Ni 6 (OH) 2 (H 2 O) 3 (en)(B-α-AsW 9 O 34 )] 2 [W 4 O 16 ][Ni 3 (H 2 O) 2 (en)] 2 }·16H 2 O (Figure S9a,b)39, the square {W 4 } group in K 32 Na 16 [{(SeO 3 )W 10 O 34 } 8 {Ce 8 (H 2 O) 20 }(WO 2 ) 4 (W 4 O 12 )]·81H 2 O (Figure S9c)20, and the S-shaped {W 4 } group in K 12 Na 22 [{(SeO 3 )W 10 O 34 } 8 {Ce 8 (H 2 O) 20 }(WO 2 ) 4 {(W 4 O 6 )Ce 4 (H 2 O) 14 (SeO 3 ) 4 (NO 3 ) 2 }]·79H 2 O (Figure S9d)20. On the other hand, when the [B-α-AsW 9 O 33 ] 9− units are simplified as polyhedra (Fig.…”

“…However, relevant reports on lanthanide (Ln) encapsulated nanosized ploy(POM)s (LENPs) are very limited. Since the pioneer work involving compact water-soluble LENP [As III 12 Ce III 16 (H 2 O) 36 W 148 O 524 ] 76− was reported by Pope in 199714, some novel LENPs have been continuously discovered such as [(PEu 2 W 10 O 38 ) 4 (W 3 O 14 )] 30−  15, [K⊂{Eu(H 2 O) 2 (α-AsW 9 O 33 )} 6 ] 35−  16, [Cs⊂{Eu(H 2 O) 2 (α- AsW 9 O 33 )} 4 ] 23−  16, [Ce 20 Ge 10 W 100 O 376 (OH) 4 (H 2 O) 30 ] 56−  17, [Gd 8 As 12 W 124 O 432 (H 2 O) 22 ] 60−  18, [Tb 8 (pic) 6 (H 2 O) 22 (B-β- AsW 8 O 30 ) 4 (WO 2 (pic)) 6 ] 12−  19, and [{(XO 3 )W 10 O 34 } 8 {Ce 8 (H 2 O) 20 }(WO 2 ) 4 (W 4 O 12 )] 48− (X = Se IV , Te IV )20. Evidently, the majority of above-mentioned LENPs were synthesized in the multi-stepwise program by reaction of prefabricated lacunary POM precursors with Ln ions.…”