Multicomponent Cooperative Assembly of Nanoscale Boron-Rich Polyoxotungstates with 22 and 30 Boron Atoms

Abstract

Open AccessCCS ChemistryRESEARCH ARTICLE1 Apr 2022Multicomponent Cooperative Assembly of Nanoscale Boron-Rich Polyoxotungstates with 22 and 30 Boron Atomsa Yi Chen, Zheng-Wei Guo, Xin-Xiong Li, Shou-Tian Zheng and Guo-Yu Yang Yi Chen State Key Laboratory of Photocatalysis on Energy and Environment, College of Chemistry, Fuzhou University, Fuzhou, Fujian 350108 , Zheng-Wei Guo State Key Laboratory of Photocatalysis on Energy and Environment, College of Chemistry, Fuzhou University, Fuzhou, Fujian 350108 , Xin-Xiong Li State Key Laboratory of Photocatalysis on Energy and Environment, College of Chemistry, Fuzhou University, Fuzhou, Fujian 350108 , Shou-Tian Zheng *Corresponding authors: E-mail Address: [email protected] E-mail Address: [email protected] State Key Laboratory of Photocatalysis on Energy and Environment, College of Chemistry, Fuzhou University, Fuzhou, Fujian 350108 and Guo-Yu Yang *Corresponding authors: E-mail Address: [email protected] E-mail Address: [email protected] MOE Key Lab of Cluster Science, School of Chemistry and Chemical Engineering, Beijing Institute of Technology, Beijing 102488 https://doi.org/10.31635/ccschem.021.202100774 SectionsSupplemental MaterialAboutAbstractPDF ToolsAdd to favoritesDownload CitationsTrack Citations ShareFacebookTwitterLinked InEmail This work demonstrates that the introduction of positive lanthanide (Ln) and transition metal (TM) cations into polyoxotungstates (POTs) to stabilize negative oxoboron clusters is a feasible and general synthetic strategy for creating not only rare boron-rich POTs but also intriguing multicomponent composite polyoxometalates (POMs). By this strategy, a large family of unprecedented boron-rich POTs with 22 and 30 boron atoms, such as [(B18Si3Ln6O36(OH)14){B4Ni4O10(OH)4(A-α-SiW9O34)}3]44− ( 1Ln), [(B19Si2Ln7O35(OH)15(H2O)){B4Ni4O10(OH)4(A-α-SiW9O34)}2{B3Ni4O9(OH)3(A-α-SiW9-O34)}]41− ( 2Ln), where Ln is Gd, Tb, and Dy, and [(B22O42){LnNi3(OH)3(B-α-SiW9O34)}4]34− ( 3Ln; Ln is Sm, Gd, and Tb), have been obtained. These POTs incorporate the largest number of boron atoms and the highest-nuclearity oxoboron clusters of any molecular POTs reported to date. The results show the fusion of two distinct research areas of POT chemistry and oxoboron cluster chemistry. In addition, they also show a family of unique POMs made from multiple oxo clusters including W–O, B–O, TM–O, and Ln–O. Experiments indicate these novel composite materials can exhibit effective catalytic activity for oxidizing toxic 2-chloroethyl ethyl sulfide. Download figure Download PowerPoint Introduction Polyoxotungstates (POTs) are anionic tungsten-oxo clusters with tunable acid-base and redox properties. Their wide potential applications in diverse areas (e.g., catalysis, electrochemistry, medicine, etc.) have rendered new POTs a prime target in new materials design.1–18 Due to the interesting magnetic and electronic properties of transition metals (TMs), one of the most extensive studies in new POTs design is the introduction of TMs or TM-oxo clusters into POTs for creating TM-incorporated POTs. After decades of effort, a library of TM-incorporated POTs has been synthesized and constitutes the largest subclass of POTs.10–18 Particularly, it has been possible to introduce dozens of TMs into a molecular POT to give fascinating high-nuclearity TM-incorporated POTs, such as Mn19-,12 Fe28-,13 Co16-,14 Ni25-,15 Cu20-,16 Zr24-,17 and Ag18-containing POTs.18 In addition to TM-incorporated POTs, many groups have also been working on the development of Ln-incorporated POTs (Ln = lanthanide) because of their intriguing luminescence and magnetic properties.5,19–29 Currently, hundreds of Ln-incorporated POTs have been obtained and comprise another important subclass of POTs. As found in TM-incorporated POTs, a handful of POTs with dozens of Ln centers has also been achieved.5,25–29 Compared with the extensive studies on TM- and Ln-incorporated POTs, research on the incorporation of nonmetal clusters into POTs is still in a nascent stage. Oxoboron cluster chemistry has acquired a significant place in the area of inorganic chemistry because of their evolving structural diversity and important applications in many fields, such as glasses, ceramics, retardant coatings, nonlinear optical materials, and so on.30–32 The incorporation of versatile oxoboron clusters into POTs not only can create brand-new composite B-rich POT materials with interesting chemical and physical properties but also is of significant scientific interest because it paves the way toward the exploration of undeveloped interdisciplinary areas of oxoboron chemistry and POT chemistry. However, the construction of such composite POTs proves challenging. Known B-containing POTs are restricted to several kinds of examples incorporating a few separated BO3/BO4 units or low-nuclearity oxoboron clusters such as binuclear B2O6.33–35 Difficulties achieving B-rich POTs are likely due to the great stability of oxoboron clusters and the repulsion between negative POTs and negative oxoboron clusters. Based on the above research interests and synthetic challenge, there is a strong impetus to develop an effective synthetic strategy for constructing novel B-rich composite POT materials. Herein, we report a general method to assemble B-rich POTs via multicomponent charge and symmetry matching among Ln3+, TM2+, borates, and POTs. A large family of unprecedented B-rich POTs, including B30-incorporated POTs [(B18Si3Ln6O36(OH)14){B4Ni4O10(OH)4(A-α-SiW9O34)}3]44− ( 1Ln) and [(B19Si2Ln7O35(OH)15(H2O)){B4Ni4O10(OH)4(A-α-SiW9O34)}2{B3Ni4O9(OH)3(A-α-SiW9O34)}]41− ( 2Ln), where Ln is Gd, Tb, and Dy, and B22-incorporated POTs [(B22O42){LnNi3(OH)3(B-α-SiW9O34)}4]34− ( 3Ln; Ln is Sm, Gd, and Tb), have been obtained, showing the largest B-containing POTs so far. The 1Ln and 2Ln series contain the largest number of B atoms in the reported POTs, whereas the 3Ln series, containing unique 22-nuclearity oxoboron clusters B22O42, consist of POTs with the highest-nuclearity oxoboron clusters in known POTs. Notably, unifying multiple different structural modes in the same molecule without phase separation is of special interest because it is a powerful method to explore new interdisciplinary research areas and create novel composite materials. Such combination is usually a significant challenge, especially for the integration of more than three kinds of different clusters in the same molecule because a common occurrence during the synthesis of multicomponent molecules is the partitioning of different structural modes into separate phases. The B–O, Ln–O, TM–O, and POT clusters have distinct structural features and properties. Fascinatingly, the 1Ln, 2Ln, and 3Ln series are the first family of composite materials incorporating the above four types of oxoclusters in the same molecule, indicating that their synthetic route can be an intriguing strategy for creating novel multicomponent composite materials. Experimental Methods Synthesis of 1Gd A mixture of Na10[A-α-SiW9O34]·18H2O (0.419 g, 0.142 mmol), Ni(Ac)2·4H2O (0.099 g, 0.398 mmol), Gd(NO3)3·6H2O (0.087 g, 0.193 mmol), and NaBO3·4H2O (0.164 g, 1.066 mmol) was mixed in 2 mL borate buffer solution (pH 12). After stirring for 1 h, the resulting mixture was sealed in a glass vial (20 mL) and heated at 80 °C for 6 days. After cooling to room temperature, green crystals were obtained. Yield: ca. 60 mg (12.0%, based on W). The pH values before and after reaction are 11.0 and 9.0, respectively. Inductively coupled plasma (ICP) analyses (based on dried sample) (%): calcd for B30H75Gd6Na5Ni12O199Si6W27: B, 3.10; Si, 1.61; Na, 1.10; Ni, 6.72; Gd, 9.00; W, 47.37. Found: B, 2.93; Si, 1.52; Na, 1.32; Ni, 6.82; Gd, 9.29; W, 46.67. Infrared (IR) (KBr, cm−1): 3372 (m), 1636 (m), 1515 (s), 1384 (m), 1348 (w), 1073 (m), 976 (s), 935 (m), 874 (s), 857 (s), 803 (s), 763 (s), 660 (s), 505 (s), 444 (s). Synthesis of 1Tb and 1Dy Compounds 1Tb and 1Dy were obtained by a similar method as described for 1Gd except for the replacement of Gd(NO3)3·6H2O with Tb(Ac)3·6H2O (0.088 g, 0.249 mmol) and Dy(NO3)3·6H2O (0.088 g, 0.193 mmol), respectively. Synthesis of 2Gd A mixture of Na10[A-α-SiW9O34]·18H2O (0.352 g, 0.120 mmol), Ni(Ac)2·4H2O (0.102 g, 0.410 mmol), Gd(NO3)3·6H2O (0.087 g, 0.193 mmol), and Li2B4O7 (0.085 g, 0.503 mmol) was mixed in 4 mL borate buffer solution (pH 9). After stirring for 1 h, the resulting mixture was sealed in a Teflon-lined autoclave (23 mL) and heated at 80 °C for 6 days. After cooling to room temperature, pale green crystals were obtained. Yield: ca. 45 mg (10.8%, based on W). The pH values before and after reaction are 9.0 and 9.0, respectively. ICP analyses (based on dried sample) (%): calcd for B31H88Gd7Na20Ni12O214Si5W27: B, 2.99; Si, 1.25; Na, 4.10; Ni, 6.28; Gd, 9.81; W, 44.25. Found: B, 2.78; Si, 1.18; Na, 4.38; Ni, 6.05; Gd, 10.06; W, 43.72. IR (KBr, cm−1): 3366 (m), 1630 (m), 1521 (s), 1385 (m), 1342 (w), 1083 (m), 977 (w), 934 (m), 874 (s), 854 (m), 804 (m), 665 (m), 507 (s), 445 (s). Synthesis of 2Tb and 2Dy Compounds 2Tb and 2Dy were obtained by a similar method as described for 2Gd except for the replacement of Gd(NO3)3·6H2O with Tb(Ac)3·6H2O (0.088 g, 0.249 mmol) and Dy(NO3)3·6H2O (0.088 g, 0.193 mmol), respectively. Synthesis of 3Gd A mixture of Na10[A-α-SiW9O34]·18H2O (0.560 g, 0.190 mmol), Ni(Ac)2·4H2O (0.102 g, 0.410 mmol), Gd(NO3)3·6H2O (0.087 g, 0.193 mmol), and K2B10O16·8H2O (0.125 g, 0.213 mmol) was mixed in 4 mL borate buffer solution (pH = 9). After stirring for 1 h, the resulting mixture was sealed in a glass vial (20 mL) and heated at 100 °C for 5 days. After cooling to room temperature, pale green crystals were obtained. Yield: ca. 50 mg (8.8%, based on W). The pH values before and after reaction are 9.0 and 9.0, respectively. ICP analyses (based on dried sample) (%): calcd for B22H60Gd4K3Na7Ni12O203Si4W36: B, 2.00; Na, 1.36; Si, 0.95; K, 0.99; Ni, 5.93; Gd, 5.30; W, 55.75. Found: B, 1.86; Na, 1.52; Si, 0.83; K, 1.09; Ni, 5.80; Gd, 5.12; W, 54.19. IR (KBr, cm−1): 3350 (m), 1634 (m), 1323 (w), 1180 (w), 1084 (s), 980 (m), 935 (s), 850 (s), 779 (s), 675 (s), 475 (s). Synthesis of 3Sm and 3Tb Compounds 3Sm and 3Tb were obtained by a similar method as described for 3Gd except for the replacement of Gd(NO3)3·6H2O with Sm(Ac)3·6H2O (0.088 g, 0.255 mmol) and Tb(Ac)3·6H2O (0.088 g, 0.249 mmol), respectively. Oxidative decontamination of 2-chloroethyl ethyl sulfide In a typical experiment, a mixture of 2-chloroethyl ethyl sulfide (CEES; 0.5 mmol), 1,3-dichlorobenzene (internal standard, 0.25 mmol), and complex 1Gd (0.006 mmol) were dispersed in acetonitrile (4 mL). After stirring the mixture for 2 min at room temperature, 30% aqueous H2O2 (0.78 mmol) was added to initiate the reaction. The reaction samples were heated at 60 °C and stirred for 2 h. The reaction was monitored by gas chromatography and the products were qualitatively analyzed by gas chromatography–mass spectrometry (GC–MS). After reactions were completed, catalysts were separated by centrifugation, washed with acetonitrile several times, and dried at 45 °C in a vacuum oven prior to use for further characterization. Results and Discussion Although 1Ln, 2Ln, and 3Ln have complex composition, their multiple components are well organized, forming a multishell-like configuration of [email protected]@[email protected] Due to isomorphism, 1Gd, 2Gd, and 3Gd are chosen as representatives of 1Ln, 2Ln, and 3Ln and discussed in detail, respectively. Structural analysis of 1Gd Reaction of [A-α-SiW9O34]10− ({A-SiW9}) with Gd3+, Ni2+, and NaBO3 · 4H2O (sodium peroxyborate) in H3BO3/NaOH buffer solution (pH 12) gave a B-rich POT 1Gd with idealized C3-symmetry. In 1Gd, the B-shell consists of 30 B atoms: two B9O15(OH)6 ({B9}) nonamers, three B2O4(OH)2 ({B2}) dimers, and six BO3 monomers (colored as turquoise in Figure 1). The protonated O atoms in motifs {B9} and {B2} were identified by bond valence sum (BVS) calculations ( Supporting Information Figure S1).36 The {B9} (B/O = 9/21) motif shows a new B–O nonamer made of three BO2(OH) triangles and six BO4 tetrahedra; its topology is different from those of the five known B–O nonameric motifs of B9O13(OH)4 (B/O = 9/17),37 B9O12(OH)6 (B/O = 9/18),38 B9O19,39 B9O17(OH)2,40 and B9O16(OH)3 (B/O = 9/19).41 Uniquely, among these B–O nonamers, the {B9} cluster in 1Gd is the only one with more BO4 tetrahedra than BO3 triangles ( Supporting Information Figure S2). As shown in Figure 1a, one BO2(OH) triangle and two BO4 tetrahedra are linked to each other via oxygen-sharing to give a three-ring B3O6(OH)2. Then, three such three-rings are joined together through three corner-sharing BO4 tetrahedra to form the tripod-like {B9} cluster with C3-symmetry. Furthermore, two {B9} clusters, arranged in a foot-to-foot orientation, are bridged by three SiO4 tetrahedra via six B–O–Si bridges to give a novel trigonal-prism cage [B18Si3O36(OH)12]18− ({B18Si3}) approximately 12 × 7.5 × 7.5 Å3 in dimension (Figure 1a), in which the Si–O and B–O bond lengths are in the ranges of 1.616–1.649 Å and 1.338–1.535 Å, respectively. The bridging Si atoms should originate from the partial decomposition of precursor {A-SiW9}. Figure 1 | (a–c) View of different structural motifs in 1Gd. (d) The structure of 1Gd. GdO9, purple; WO6, red; SiO4, yellow; NiO6, green. Download figure Download PowerPoint The anionic and hollow {B18Si3} cage is stabilized by the encapsulation of two cationic planar triangular [Gd3(μ3-OH)]8+ units into its inner cavities via the coordination of O atoms from the {B18Si3} cage to further form the [B18Si3Gd6O36(OH)14]2− ({B18Si3Gd6}) cluster, of which 12 O atoms act as linkers between Gd3+ ions to form the innermost Gd-shell of a D3h-symmetry hexanuclear core Gd6O12(OH)2 ({Gd6}) with trigonal prismatic shape (Figure 1b). In addition to coordinating with one μ3-OH group and six O atoms from the {B18Si3} cage, each Gd3+ ion is also chelated by a BO3 unit to form a nine-coordinate geometry with a distorted tricapped trigonal prism with Gd–O distances of 2.344–2.551 Å ( Supporting Information Figure S3). The combination of Gd- and B-shell gives rise to a B–Gd–O cluster [B24Si3Gd6O54(OH)14]20− ({B24Si3Gd6}, Figure 1b), representing an uncommon fusion of two areas of B–O and Ln–O clusters. In addition to chelating to Gd3+ ions, six BO3 units in 1Gd also bond to Ni2+ ions, serving as bridges between the Gd- and Ni-shell. Specifically, the Ni-shell contains a total of 12 Ni2+ ions. Every four Ni2+ ions adopt a pyramidal array templated by a trivacant {A-SiW9}, where adjacent Ni2+ ions are bridged by two μ3-OH groups, two BO3 units, and one {B2} dimer to form a B–Ni–O motif B4Ni4O10(OH)4 ({B4Ni4}, Figure 1c). Thus, each BO3 unit bonds to one Gd3+ and two Ni2+ ions. With the {B4Ni4} clusters located in the vacant sites of [A-SiW9], three Ni-substituted POT motifs [B4Ni4O10(OH)4](A-α-SiW9O34) ({B4Ni4(A-SiW9)}) are formed (Figure 1c). Through the connections of six BO3 bridges, the {B18Si3Gd6} cluster is surrounded by three {B4Ni4(A-SiW9)} motifs, giving a B30-incorporated 1Gd, that is, {B18Si3Gd6}@{B4Ni4(A-SiW9)}3≡({Gd6}@{B18Si3})@{B4Ni4(A-SiW9)}3 (Figure 1d), which is the first B-rich POT with dozens of boron atoms. What is more, it is also the first time that the p-block boron is shown capable of coassembling with both d- and f-block metals in POM chemistry. The structure of 1Gd is quite flexible in chemical compositions, and a series of isomorphic 1Ln compounds with other Ln ions, such as Tb and Dy, have also been obtained ( Supporting Information Figure S4). Inherent multicomponent cooperative interactions in 1Ln The successful incorporation of a large number of boron atoms into POTs is attributed to the combination of 4f Ln and 3d TM cations with POT and borate polyanions. On the one hand, the formation of series 1Ln with a multishell-like configuration of [email protected]@[email protected]({Gd6}@{B24Si3}@{Ni4}3@{SiW9}3) is related to the inherent multicomponent cooperative charge-matching interaction of [email protected]@[email protected] And on the other hand, the geometry match between different components also plays a key role in the cooperative assembly of 1Ln. In 1Gd for example, through coordination of Gd3+ cations with BO3, BO4, and SiO4 units, the innermost Gd3(μ3-OH) motifs template the formation of the{B18Si3} cage and transfer their C3-symmetry through the cage to the whole molecule 1Gd. Instead of Ni2+ ions, Gd3+ ions are situated at the innermost core as templates due to their more variable coordination numbers and flexible coordination modes compared with Ni2+ ions, which place fewer structural restrictions on the resulting oxoboron architectures and thus favor formation of various oxoboron motifs. Furthermore, compared with Ni2+ ion, the longer Gd–O distance and higher coordination number and positive charge of Gd3+ ion also provide some advantages because they might contribute to the formation of larger B–O clusters and thus help to reduce the steric hindrance among the outer nanoscale POT polyanions. On the contrary, the lacunary Keggin POT precursors prefer to trap octahedral NiO6 into their vacant sites to generate more stable plenary Keggin clusters. So, the formation of 1Gd reveals that the multicomponent cooperative assembly of Ln, TM, borate, and POTs is a feasible synthetic method for making unprecedented B-rich POTs. Structural diversity The p-block B–O cluster, f-block Ln–O cluster, and d-block TM–O and W–O clusters have distinct structural features and properties. Their unification in the same molecule has never been observed. Apart from the B-rich feature, 1Ln also represents the first series of species integrating the above four kinds of clusters in the same molecule and exhibits a series of 2p–3p–3d–4f–5d-element-based composite structures. Such a multicomponent system can lead to great compositional diversity. Especially, the multiple components endow the synthetic strategy with a large reaction parameter space, making it also a versatile method to create diverse B-rich POTs. For example, the use of different starting borate salts produces different multicomponent B-rich POTs. Structural analysis of 2Gd The replacement of NaBO3·4H2O in the reaction of 1Gd with Li2B4O7 produced a new composite 2Gd; its structure resembles that of 1Gd but there are three main structural discrepancies between them. First, it is interesting to find that one of three four-coordinate Si linkers in the {B18Si3} cage of 1Gd can be substituted by a seven-coordinate Gd3+ ion to form the {B18Si2Gd} cage found in 2Gd (Figure 2a), in which the pentagonal dipyramidal coordination sphere of the Gd3+ ion comprises two Gd–O–B bridges to two {B9} motifs, two Gd–O–Gd bridges to the innermost {Gd6} core, two Gd–O–B bridges to one BO3 unit, and one terminal water ligand. Thus, the innermost Gd–O core in 2Gd turns into a heptanuclear Gd7O12(OH)2(H2O) ({Gd7}) cluster with capped trigonal prism shape, which can be derived from the trigonal prismatic {Gd6} core in 1Gd with one of its three side faces capped by an extra Gd3+ ion. Figure 2 | (a and b) View of different structural motifs in 2Gd. (c) The structure of 2Gd. GdO9/GdO7, purple; WO6, red; SiO4, yellow; NiO6, green. Download figure Download PowerPoint Second, the substitution of the rigid SiO4 tetrahedron with the relatively flexible GdO7 capped trigonal prism endows the {Gd7} core of 2Gd with a more tunable inner cage space compared with the corresponding SiGd6O12(OH)4 part of 1Gd. As a result, the {Gd7} core can enclose a central B atom through its three μ3-O atoms (B–O distances of 1.380–1.438 to form a [email is that the of a B atom a cage is quite the symmetry of the innermost Gd–O clusters from D3h-symmetry {Gd6} to {Gd7} also the of the assembly of 2Gd. As shown in Figure by the incorporation of the extra Gd3+ ion, a {B2} motif from a Ni-substituted {B4Ni4(A-SiW9)} of 2Gd is by a BO3 forming a cluster, so that the extra Gd3+ ion can be chelated by the BO3 to form a stable seven-coordinate pentagonal dipyramidal geometry and to Ni2+ ions to stabilize the Thus, those in 1Gd, the coordination modes of three outer Ni-substituted POT motifs in 2Gd are not a symmetry from a C3-symmetry 1Gd to an 2Gd, (Figure The results further the template role of the innermost ions. isomorphic compounds 2Ln with Ln as Tb and can be made ( Supporting Information Figure Structural analysis of 3Gd Fascinatingly, the replacement of Li2B4O7 in the reaction of 2Gd with a novel also showing a [email protected]@[email protected] As shown in Figure the innermost Gd-shell consists of four Gd3+ ions in an idealized with a distance of by a assembly the the B-shell shows a 22-nuclearity B–O cluster made of six three-rings together by four BO3 the three-ring in 1Gd formed by two BO4 tetrahedra and one BO2(OH) the three-ring in 3Gd is by one BO4 group and two BO3 triangles (B–O bond that the topology of such a cluster has not been in oxoboron cluster chemistry. Figure | (a and b) View of different structural motifs in (c) The structure of GdO9, purple; WO6, red; SiO4, yellow; NiO6, green. Download figure Download PowerPoint of the cluster that six three-rings are located at six of the by four Gd3+ ions (Figure four BO3 triangles are at four and with BO4 tetrahedra from The connections between the Gd- and B-shell gives a hollow cage with a of ca. Furthermore, each of the cage is capped by three NiO6 through six and three bridges to give a larger cluster Figure in which each Gd3+ ion is by six O atoms from the cage and three O atoms from a core to form a tricapped trigonal prism with Gd–O bond lengths of from the reaction of the precursor in the reactions of 1Ln and 2Ln, the 3Gd reaction an from to By coordinating to four are to four of the cluster, resulting in the formation of the 3Gd with a of ca. (Figure is interesting to that the of the core with three NiO6 to this because the lacunary can only three corner-sharing = the lacunary can trap three ( Supporting Information Figure The replacement of starting Gd3+ ion with other ions (e.g., and in this also a series of isomorphic compounds 3Ln ( Supporting Information Figure the of the of the largest B–O cluster that has been into a POT is not more than 3Ln represents a series of POTs containing the highest-nuclearity oxoboron Chen important research on the incorporation of into POTs through a strategy and made novel POT by = or cluster units and the linkers of to the above we another of research on the incorporation of inorganic oxoboron clusters into POTs via a multicomponent cooperative With the strategy, we create series of novel POM made of POTs joined together by high-nuclearity B-rich clusters. and 1Gd, 2Gd, and 3Gd were as metal salts of ( ( and ( their were by and ICP and their phase were by ( Supporting Information and the of and should be added to and respectively. These be located and are to be on the which is common in these inorganic compounds are in water but in many such as and POMs have potential applications in and the of toxic chemical has 1Gd was chosen as a to its catalytic in the decontamination of a (Figure Figure 4 | of 1Gd as for the of and of 1Gd, shown by the and of the catalytic of respectively. and and IR of 1Gd before and after catalytic respectively. of and values for 1Gd. The are to the Download figure Download PowerPoint The was in a system by mg 1Gd in a solution of 0.5 0.25 1,3-dichlorobenzene (internal and 4 mL After stirring the mixture for 4 min at room temperature, 30% aqueous H2O2 (0.78 mmol) was and the mixture was heated at 60 °C and stirred for 2 h. The results that 1Gd can of toxic into a toxic 2-chloroethyl ethyl a time of 2 with to and The of reaction of is approximately The is higher than those of some catalytic materials, such as and metal A without 1Gd the same only is the of 1Gd, the 1Gd was from the reaction solution by at the of each washed with and dried vacuum at The dried was in a The results the 1Gd can be without significant of activity at to the (Figure Furthermore, IR and were to the stability of 1Gd during the catalytic the IR and the of the 1Gd after the catalytic reaction were with those of crystals of 1Gd and that 1Gd its structural during the of catalytic reaction. The effective catalytic and of 1Gd it a for the of In addition, 1Tb and 3Tb were as examples for characterization. magnetic were in the with an magnetic of 1 (Figure The values of 1Tb and 3Tb at are and K, respectively. The is with the of for 12 Ni2+ ions with = 1 and = and 6 ions with = 6 and = and the is than the of for 12 Ni2+ ions with = 1 and

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