New assembly of transition metal complexes based on [GeW9O34]10− building blocks: Syntheses, crystal structures and magnetic properties

Study on Catalytic Water Oxidation Properties of Polynuclear Manganese Containing Polyoxometalates

“…In order to verify that the MnxPOMs were synthesized according to the literature, their infrared spectra were measured. As shown in Figure 6, we can observe the main characteristic vibration frequencies at 991, 945, 898, 779 and 710 cm −1 (as shown in Figure 6a), four weak peaks at 662, 642, 538 and 480 (internal diagram in Figure 6a); the main characteristic vibration frequencies at 1105, 1060, 944, 778, 620, 592 and 500 cm −1 (as shown in Figure 6b); the main characteristic vibration frequencies at 941, 875, 770, 696 and 458 and the weak peaks at 509 cm −1 (as shown in Figure 6c); the main characteristic vibration frequencies at 1626, 940, 877, 775, 725 and 509 cm −1 (as shown in Figure 6d); the main characteristic vibration frequencies at 1629, 1465, 1438, 1408, 1385, 1020, 943 and 750 cm −1 ; and the weak peaks at 676, 631, 597, 569, 487 and 467 cm −1 in the illustration (as shown in Figure 6e); The main characteristic vibration frequencies at 988, 945, 895, 793, 711, 646 and 536 cm −1 (as shown in Figure 6f) are consistent with the infrared characteristic peaks of Mn2-POM [13], Mn4-POM [14,20], Mn6-POM-1 [15], Mn6-POM-4 [16], Mn14-POM [17] and Mn19-POM [18] in the literature, which proves that we have successfully prepared the above six MnxPOMs. There are some small differences between the measured and reported values, which may be caused by the different instrument used.…”

“…Mn x POMs were synthesized according to the literature [13][14][15][16][17][18]. Please see supplementary information for details.…”

“…At present, the catalytic water oxidation properties of some manganese containing POMs have been studied separately [7][8][9][10][11][12], the effects of amount, oxidation state of Mn ions and Mn-O cluster structure on the catalytic performance for water decomposition have hardly been reported. In order to select Mn-POMs with good catalytic performance, and find the influence of amount, oxidation state and Mn-O cluster structure, we selected six MnxPOMs as representative for comparison, including two manganese containing POMs: [Mn II Mn III SiW10O37(OH)(H2O)] 6− (Mn2-POM) [13] and four manganese containing POM: [Mn II 3Mn III (H2O)2(PW9O34)2] 9− (Mn4-POM) [14], six manganese containing POMs: [Mn II 4Mn III 2Ge3W24O94(H2O)2] 18− (Mn6-POM-1) [15], [Mn III 2Mn II 4(μ3-O)2(H2O)4(B-β-SiW8O31)(B-β-SiW9O34)(γ-SiW10O36)] 18− (Mn6-POM-4) [16], 14 manganese containing POM: [{Mn III 3Mn IV 4O4(OH)2(OH2)}2(W6O22)(H2W8O32)2(H4W13O46)2] 26− (Mn14-POM) [17] and 19 manganese containing POM [Mn II 19 (OH)12(SiW10O37)6] 34− (Mn19-POM) [18]. It is hoped that certain laws can be found for researchers' reference.…”

“…The structure is shown in Figure 1b. Mn6-POM-1 was synthesized from Na2WO4, GeO2, HCl, Mn(CH3COO)2•4H2O and imidazole at 90 °C [15]. The compound is composed of two Keggin units with three manganese substituted [Mn3GeW9O34] 4− and a six-vacancy bridged cluster [GeW6O26] 12− .…”

Two New Sandwich-Type Manganese {Mn5}-Substituted Polyoxotungstates: Syntheses, Crystal Structures, Electrochemistry, and Magnetic Properties

“…However, a few examples, mainly pentanuclear, hexanuclear − and nonanuclear based on Cu II and Zn II -substituted sandwich-type POMs, have been reported. It is worth noting that paramagnetic multinuclear manganese-substituted complexes are attractive in numerous fields. − Moreover, there is development of manganese complexes exhibiting single-molecule magnet (SMM) behavior. − To date, a few examples of Mn-ion-substituted complexes, such as dinuclear [(α-AsW 9 O 33 ) 2 ­WO­(H 2 O)­Mn 2 (H 2 O) 2 ] 10– , [Mn 2 (H 2 O) 6 ­(WO 2 ) 2 ­(SbW 9 O 33 ) 2 ] 10– , and [(Mn­(H 2 O) 3 ) 2 ­(WO) 2 ­(β-BiW 9 O 33 ) 2 ] 10– and trinuclear [As 2 W 18 ­{Mn­(H 2 O)} 3 O 66 ] 12– , [(Mn III ­(H 2 O)) 3 ­(SbW 9 O 33 ) 2 ] 9– , and [Mn II ­(H 2 O)­Mn 2 (AsW 9 O 33 ) 2 ] 12– , were reported. Yamase et al reported Mn II -substituted sandwich-type polyoxotungstates [(MnCl) 6 (XW 9 O 33 ) 2 ] 12– (X = As III and Sb III ) and characterized their magnetic properties. , The synthetic strategy to obtain novel polynuclear TMSPs with new structural varieties and manifold properties continues to be a focus of considerable ongoing research.…”