CeTiOx脱硝催化剂的抗硫中毒性能

分别以Ce₂(C₂O₄)₃和Ce(SO₄)₂为Ce前驱体, 采用固相球磨法制备了Ce基选择性催化还原(SCR)脱硝催化剂CeTiO_x-A[以Ce₂(C₂O₄)₃为前驱体]和CeTiO_x-B[以Ce(SO₄)₂为前驱体]. 将2个催化剂分别在体积分数为0.15%的SO₂的气氛下反应40和60 h, 得到高硫条件下SCR反应后的CeTiO_x催化剂, 分别记为40CeTiO_x-A, 60CeTiO_x-A, 40CeTiO_x-B和60CeTiO_x-B. 考察了反应前后催化剂的NH₃-SCR反应活性. 采用X射线衍射(XRD)、 X射线荧光光谱(XRF)、 比表面积(BET)测试、 H₂程序升温还原(H₂-TPR)、 X射线光电子能谱(XPS)、 NH₃程序升温脱附(NH₃-TPD)及SO₂程序升温脱附(SO₂-TPD)等技术对样品进行了表征. 结果表明, CeTiO_x-A系列催化剂比CeTiO_x-B系列催化剂具有更高的NH₃-SCR反应活性和更好的抗硫抗水性能. 与CeTiO_x-B系列催化剂相比, CeTiO_x-A系列催化剂具有更大的比表面积和孔容, 更多的Ce³⁺和吸附氧(O_α)物种有助于NO的吸附和活化; CeTiO_x-A系统催化剂还具有更多的Lewis强酸性位数量, 可以吸附更多的NH₃分子, 有利于催化剂上NH₃-SCR反应的进行, 提高了CeTiO_x-A系列催化剂的NO转化率.     

核-壳结构多酸/磁性铈铁纳米复合氧化物@SiO2吸附-氧化脱硫性能

水热法合成了铈铁纳米复合氧化物,采用化学沉积法在其表面包裹SiO₂制备核-壳结构磁性材料,以其为载体负载H₂O₂结合Keggin结构磷钼酸(HPMo)制备了HPMo-H₂O₂/CeFe_xO_y@SiO₂吸附-氧化脱硫催化剂。 采用扫描电子显微镜(SEM)、透射电子显微镜(TEM)、傅里叶红外光谱(FT-IR)、X射线粉末衍射(XRD)、氮气吸附脱附(BET)、³¹P魔角核磁共振(MAS-NMR)和X射线光电子能谱(XPS)等对催化剂的结构进行表征。 结果表明,SiO₂将CeFe_xO_y包裹形成核-壳结构纳米复合材料,以其为载体负载HPMo-H₂O₂后Keggin型多酸的骨架结构保持,并产生少量过氧化磷钼酸盐活性物种。 不同催化剂对有机硫化物二苯并噻吩(DBT)的吸附脱硫和氧化脱硫性能,均呈现出HPMo-H₂O₂/CeFe_xO_y@SiO₂＞CeFe_xO_y@SiO₂＞CeFe_xO_y的活性顺序,多酸的引入大大提升了其对大分子有机硫化物的吸附和氧化脱除性能,催化氧化脱硫活性的提高源于多酸分子“假液相”反应过程的结果。 在反应温度60 ℃,反应3 h,m(油)∶m(催化剂)=35∶1,n(O)∶n(S)=10∶1的条件下,对DBT氧化脱除率达到99.4%。 制备的磁性核-壳结构氧化脱硫剂有理想的氧化脱除DBT的循环使用性能,并且可通过外加磁场进行简单分离,是一类制备方法简单、催化活性高且稳定性好的绿色环保型催化剂。     

Keggin型钼钒磷杂多酸催化剂上丙烷选择氧化性能的研究

系统研究了不同数目V⁵⁺取代的钼钒磷杂多酸H_3+nPMo_12－nV_nO₄₀ (n＝0～4)催化剂上丙烷选择氧化反应性能. 通过BET, IR, TPR, 紫外-可见光谱等表征手段对催化剂的理化性质进行了考察, 并对催化剂的结构-性能关系进行了初步关联. 在杂多酸的一级结构中, V⁵⁺对Mo⁶⁺的取代不仅改变了杂多阴离子金属-氧桥的键强以及晶格氧的插入能力, 而且也相应地调变了样品的酸量. 催化剂活性随V⁵⁺取代数量的递增而增强; 适宜数量的V⁵⁺取代提高了含氧酸产物的选择性, 而过量的V⁵⁺取代则导致部分氧化产物的深度氧化. 考察了在Keggin型杂多酸二级结构上引入钒物种的影响, 也即将钒物种(VO)²⁺作为抗衡离子取代部分质子以调变催化剂的结构与性质. 实验表明, 处于一级结构和二级结构[(VO)²⁺抗衡离子]中的V在反应中均可离析出少量V₂O₅物种. 适宜量的(VO)²⁺物种以及离析出来的少量V₂O₅物种可能均对催化剂的性能有贡献. 显然, 钒在不同位置的价态变化以及形态的不同, 会导致催化性能的相应改变.     

Keggin型杂多酸铯盐催化苯羟基化反应

采用室温固相法制备了具有Keggin结构的杂多酸铯盐催化剂(Cs_xH_3+n-xPMo_12-nV_nO₄₀, n＝0, 1, 2, x＝0.5～3.0). 红外、X射线粉末衍射及循环伏安技术研究显示, 钒取代钼原子可提高催化剂的氧化还原性, 铯取代数的增加可提高催化剂的疏水性但降低氧化还原性. 在H₂O₂为氧化剂的苯羟基化反应中, 随着铯取代数目的增加, 催化剂的溶脱情况得到明显改善. 在氧化还原性和疏水性协同作用下, Cs₂H₃PMo₁₀V₂O₄₀在Cs_xH_3+n-xPMo_12-nV_nO₄₀系列催化剂中显示出相对最佳的苯羟基化催化活性(苯酚收率19.2%)和重复使用性能.     

Pd-Cu/ZrO2催化CO2加氢制甲醇的性能

采用溶胶-凝胶法制备了n(Cu):n(Zr)=1:1、1:2、1:4和1:8的Cu/ZrO₂催化剂。 实验结果表明,当n(Cu):n(Zr)=1:4时,催化剂表现出较高的CO₂转化率(8.0%)和甲醇选择性(59.5%),为了增加CO₂的转化率,提高甲醇选择性,在n(Cu):n(Zr)=1:4的催化剂中添加质量分数1%的Pd,采用浸渍法制备了Pd-Cu/ZrO₂催化剂。 在250 ℃、2 MPa、12000 mL/(g·h)和V(H₂):V(CO₂)=3:1的反应条件下,CO₂转化率和CH₃OH收率相比Cu/ZrO₂催化剂(n(Cu):n(Zr)=1:4)分别提高了40.0%和80.9%。 通过X射线衍射仪(XRD)、傅里叶变换红外光谱仪(FT-IR)、N₂吸附-脱附(BET)、X射线光电子能谱仪(XPS)和程序升温还原化学吸附仪(H₂-TPR)等仪器表征证明Pd的添加提高了催化剂的分散性和比表面积。 催化剂中Pd和Cu之间强相互作用,使Cu2p轨道结合能向低处偏移,还原温度的降低,说明Pd-Cu/ZrO₂催化剂还原能力增强,使得CO₂加氢活性提高。     

H2O2/[CnMIm]HCO3对CEES的消毒动力学及机理

合成了4种不同烷基链长的1-烷基-3-甲基咪唑碳酸氢盐([C_nMIm]HCO₃, n=2, 4, 6, 8)离子液体(ILs), 并以H₂O₂水溶液(质量分数30%)为氧化剂, 研究了H₂O₂在[C_nMIm]HCO₃离子液体、 H₂O和C₂H₅OH中对芥子气模拟剂2-氯乙基乙基硫醚(CEES)的消毒能力, 考察了离子液体烷基链长、 H₂O₂/CEES摩尔比和反应温度对消毒率的影响, 并对反应活化能和产物进行了分析. 结果表明, H₂O₂在不同溶剂中对CEES的消毒能力依次为[BMIm]HCO₃>[EMIm]HCO₃>[HMIm]HCO₃>[OMIm]HCO₃>C₂H₅OH>H₂O. 对于CEES在[BMIm]HCO₃中形成的20 mg/mL的毒剂溶液, 当n(H₂O₂)∶n(CEES)=10时, H₂O₂可在30 min内消毒99.58%的CEES, 且该体系具有一定的低温(243 K)消毒能力. 该反应为一级反应, 活化能为15.59 kJ/mol, 低于单一过碳酸钠与CEES的反应活化能. 化学发光测试结果表明, 在碳酸氢根活化过氧化氢(BAP)体系中, 咪唑基离子液体可抑制亚砜被超氧阴离子(·O^-₂)过度氧化为砜.     

氨基醇杂多酸类离子液体催化环酮的Baeyer-Villiger氧化反应

合成了一系列氨基醇杂多酸类离子液体, 并将其用于催化环酮的Baeyer-Villiger氧化反应. 以2-庚基环戊酮为模板底物, H₂O₂为氧化剂, 探究了此类氨基醇杂多酸类离子液体的催化活性, 筛选出催化活性最高的催化剂为[Pro-ps]H₂PW₁₂O₄₀, 最佳反应条件: n(2-庚基环戊酮)∶n(催化剂)∶n(H₂O₂)=1∶0.03∶4, 反应温度40 ℃, 反应时间8 h, 无溶剂. 在最佳条件下, 2-庚基环戊酮的转化率为98.19%, 产物δ-十二内酯的选择性可达82.84%. 水相中的离子液体[Pro-ps]H₂PW₁₂O₄₀经干燥后可以重复使用. 经过5次循环使用后催化活性未见明显下降. [Pro-ps]H₂PW₁₂O₄₀还可用于催化其它多种环酮的Baeyer-Villiger氧化反应, 结果表明, 该催化剂具有良好的重复使用性和底物普适性.     

Pitzer方程应用于离子液体[Cnmim][H2PO4](n= 3, 4, 5, 6)溶解焓研究

在298.15 K下,利用等温环境溶解反应热量计,测定了离子液体[C_nmim][H₂PO₄] (n= 3, 4, 5, 6) (1-烷基-3-甲基咪唑磷酸盐)在水中不同浓度的摩尔溶解热(Δ_solH_m),根据Pitzer电解质溶液理论计算得到了标准摩尔溶解焓(Δ_solH_m⁰)和Pitzer焓参数：β_MX^(0)L, β_MX^(1)L,和C^ϕL,并计算了表观相对摩尔焓。通过推导讨论,得到了离子液体[C_nmim][H₂PO₄](n= 3, 4, 5, 6)同系物每摩尔亚甲基对标准摩尔溶解焓的贡献。     

铈基与钴基Co3O4-CeO2氧载体上甲烷化学链转化特性: 产物选择性控制

采用水热法制备了Co₃O₄/CeO₂(x)[x为钴铈原子摩尔比n(Co):n(Ce)=6:49:1]和Ce_1-yCo_yO_2-δ(y=0.10.4)2个系列复合氧化物, 并表征了材料的物理化学性质, 考察了这些氧化物作为氧载体参与甲烷化学链转化(化学链燃烧和化学链部分氧化)的反应性能. 结果表明, 2类复合氧化物的甲烷反应活性均明显优于单一氧化物CeO₂或Co₃O₄, 但2类氧载体上的甲烷反应产物的选择性具有明显差异. Ce_1-yCo_yO_2-δ氧载体形成了Ce-Co-O固溶体, 储氧能力明显增强, 体相晶格氧迁移速率与甲烷活化速率匹配较好, 甲烷反应产物以CO和H₂的合成气为主, 有利于甲烷的化学链部分氧化. Co₃O₄/CeO₂(x)氧载体中CeO₂与Co₃O₄之间的相互作用改善了材料的储氧能力和氧化活性, 其与甲烷反应时主要生成CO₂, 有利于甲烷化学链燃烧. 连续性化学链循环实验表明, 2类氧载体均具有较好的再生性能和循环稳定性.     

基于Keggin型杂多酸的无机-有机杂化物的合成和光催化活性

采用水热合成方法制备了2个基于Keggin型杂多酸的无机-有机杂化物, 化学式分别为{[Cu₂(4,4′- bipy)₄(H₂O)₄](SiMo₁₂O₄₀)·18H₂O}_n(1)和{[Cu₂(4,4′-bipy)₄(H₂O)₄](PMo₆W₆O₄₀)·18H₂O}_n(2)(bipy=bipyridine). 结构分析 表明2个化合物同构, Cu²⁺是六配位, 分别与4个4,4′-bipy上的N原子和2个水分子上的O原子结合, 形成 [Cu(4,4′-bipy)₂(H₂O)₂]_n²ⁿ⁺二维层状结构. 杂多阴离子通过静电与配位阳离子[Cu(4,4′-bipy)₂(H₂O)₂]_n²ⁿ⁺作用交叉排列在层间. 通过红外光谱、 粉末X射线衍射和固体紫外-可见漫反射光谱等对化合物的性质进行了表征. 研究了所合成化合物对水溶性染料亚甲基蓝的降解活性, 发现2种化合物对于亚甲基蓝均表现出显著的光降解活性, 并对它们的催化机理进行了讨论.     

Keggin型多金属氧酸盐[XW11MoO40]n-(X=P, Si, Ge ；n=3, 4)在水和二甲基酰胺溶液中的电化学行为

The electrochemical behavior of monomolybdenum-substituted Keggin-type polyoxometalates [XW11MoO40]^n- （X=P, Si, Ge with n=3, 4） was studied in aqueous and N,N-dimethylformamide （DMF） solution. These anionic clusters showed different electrochemical behaviors in two kinds of media. The initial potentials of [XW11MoO40]^n- in DMF were more negative than those in aqueous solution, showing a lower oxidation ability of [XW11MoO40]^n- in DMF. The investigation results suggested that the redox properties of polyoxometalates be tuned by the substitutions of Mo for W and by replacing aqueous solution with organic solvent, which provided valuable information to rationally choose polyoxometalates （POM） in preparation of POM-based organic/inorganic hybrid materials.     

Modification of electrodes with nanostructured films containing dirhodium-substituted polyoxometalates

Layer-by-layer (LBL) electrostatic assembly was used to prepare films comprising generation-4 polyamidoamine dendrimers (G4-PAMAM) and dirhodium polyoxometalates (Rh₂POMs) on glassy carbon (GC) electrodes. To employ the propensity of P₂Mo₁₈O₆₂ ^6– (PMo) to directly adsorb on glassy carbon, a new compound, Rh₂PMo, was synthesized and characterized. The behavior was compared to that of a previously reported Rh₂POM prepared from PW₁₂O₄₀ ^3– (PW). The LBL assembly of (G4-PAMAM, Rh₂PW) _n bilayers on GC pretreated by formation of a monolayer of 4-aminobenzoic acid was studied by doing a linear least-squares fit of peak current to n (n=5); the result gave an r ² of only 0.90. With Rh₂PMo, the analogous experiments with n=7 gave an r ²=0.995. Strong adsorption of Rh₂PMo onto GC allowed the assembly of Rh₂PMo_adsorbed|(G4-PAMAM, Rh₂PMo) _n on conventional GC and on a 10-µm carbon fiber. The latter was used to demonstrate the bifunctional electrocatalytic property of these films through reduction of nitrite and the oxidation of arsenite.Contribution to the 3rd Baltic Conference on Electrochemistry, Gdansk-Sobieszewo, Poland, 23–26 April 2003Dedicated to the memory of Harry B. Mark, Jr. (28 February 1934–3 March 2003)     

Comparison between various Keggin and Wells–Dawson sandwich‐type polyoxometalates in catalytic oxidation of cyclooctene and cyclohexene with hydrogen peroxide

The catalytic performance of tetra‐n‐butylammonium salts of Keggin and Wells–Dawson sandwich‐type polyoxotungstates, [M₄(PW₉O₃₄)₂]^m? and [M₄(P₂W₁₅O₅₆)₂]^n? (M = Mn²⁺, Fe³⁺, Co²⁺, Ni²⁺, Zn²⁺), in the oxidation of cyclooctene and cyclohexene with 30% hydrogen peroxide under various conditions was investigated. In comparison, Wells–Dawson sandwich‐type polyoxometalates were found to be less active than Keggin ones. In both of them, those containing Zn and Fe gave higher conversions for different oxidation conditions. These catalysts showed very good reusability in the oxidation reaction. Copyright © 2014 John Wiley & Sons, Ltd.     

Aliphatic Organoimido Derivatives of Polyoxometalates Containing a Bioactive Ligand

A series of aliphatic organoimido derivatives of hexamolybdate based on amantadine, namely (nBu₄N)₂[Mo₆O₁₈(?NC₁₀H₁₅)] ( 1 ), (nBu₄N)₂ {cis‐[Mo₆O₁₇(?NC₁₀H₁₅)₂]} ( 2 ), (nBu₄N)₂{trans‐[Mo₆O₁₇(?NC₁₀H₁₅)₂]} ( 3 ), and (nBu₄N)₂[Mo₆O₁₆(?NC₁₀H₁₅)₃] ( 4 ), was synthesized in reasonable yield by dehydration with N,N′‐dicyclohexylcarbodiimide (DCC). They were characterized by IR and UV/Vis spectroscopy, elemental analysis, ESI mass spectrometry, and single‐crystal X‐ray structure analysis. The spectral and structural similarities and differences between monosubstituted, cis‐disubstituted, and trans‐disubstituted organoimido derivatives were elucidated and may provide guidance for related work on organoimido‐functionalized Lindqvist‐type polyoxometalates. In addition, trans‐disubstituted and polysubstituted derivatives containing aliphatic organoimido ligands have not yet been reported, and the crystal structure of the trans isomer may lead us to a deeper understanding of disubstituted derivatives. Furthermore, proliferation and morphology of MCF‐7 cells were studied with compound 1 . The present results show that the DCC‐dehydrating protocol could be an efficient approach to covalently graft bioactive ligands such as amantadine onto POMs and enhance their application in clinical cancer treatment.     

Anhydrous Lanthanide MOFs and Direct Photoluminescent Sensing for Polyoxometalates in Aqueous Solution

New anhydrous lanthanide metal–organic frameworks (MOFs) [Pr(tip)_1.5]_2n ( tip‐Pr ), [Nd(tip)_1.5]_2n ( tip‐Nd ), [Eu(tip)_1.5]_2n ( tip‐Eu ), and [Eu(OH)(mip)]_n ( mip‐Eu ) (tip=5‐tert‐butylisophthalate anion, mip=5‐methylisophthalate ion), have been hydrothermally synthesized and structurally characterized by elemental analyses, FT‐IR spectroscopy, single‐crystal X‐ray diffraction, thermal gravimetric analysis/differential thermal analysis (TG/DTA), and X‐ray powder diffraction (XRPD) techniques. MOFs tip‐Pr , tip‐Nd , and tip‐Eu are isostructural anhydrous compounds, and exhibit an unprecedented 3D microporous structure with hexagonal channel arrays. The selectively prepared MOF mip‐Eu presents an interpenetrated 3D microporous architecture containing the hydroxyl cluster chains. Solid‐state photoluminescence properties at room temperature indicate that both tip‐Eu and mip‐Eu display the characteristic of the Eu³⁺ ion spectrum dominated by the ⁵D₀→⁷F_J (J=0‐4) transition. Compared with mip‐Eu , tip‐Eu displays the very high solid‐state quantum yield (0.62±0.03) and longer lifetime value (0.94±0.01 ms), which is due to the absence of the hydroxyl groups from the solid‐state structure of tip‐Eu . More importantly, a new method to directly investigate the potential of solid‐state lanthanide MOFs for ionic sensing in aqueous solutions has been developed, and successfully applied it to study the potential sensing function of tip‐Eu for polyoxometalates (POMs). The possible mechanism for the quenching effect of POMs on the fluorescence of tip‐Eu is elucidated by the strongly competitive absorption of the excited light source energy between POMs and tip ligands. The very promise for the highly sensitive sensing for polyoxometalates, together with the characteristic of the reversible fluorescence response, suggest that solid‐state tip‐Eu can be an excellent candidate for the directly photoluminescent detection of POMs in aqueous solutions.     

Tin-derivative sandwich-type polyoxometalates supported on Nd-doped TiO2 nanoparticles as efficient and reusable catalysts in the oxidation of sulfides and alcohols

New nanocomposites, including different loading levels of sandwich-type polyoxometalates [(HOSn^IVOH)₃(XW₉O₃₄)₂]^n? (X = As (1), P (2) n = 12 and Si (3) n = 14) on Nd-doped TiO₂ nanoparticles were prepared by a simple impregnation method. The nanocomposites were characterized by X-ray diffraction (XRD), scanning electron microscopy, transmission electron microscopy, Fourier transform infrared (FTIR), and energy-dispersive X-ray spectroscopy. Compounds 1–3 were successfully loaded on Nd-doped crystallized anatase-phase TiO₂ nanoparticles of 20–25 nm. Catalytic activities of nanocomposites were examined by carrying out the oxidation of sulfides and alcohols with H₂O₂. Simple synthesis method, reusability, and low amounts of the heterogeneous catalysts with a slight excess of H₂O₂ and mild reaction conditions make these oxidation reactions an environmentally benign chemical process.     

Preparation,characterization and catalytic activity studies of organoruthenium‐supported polyoxotungstates on SBA‐15

Organoruthenium‐supported polyoxometalates [(RuC₆H₆)XW₉O₃₄]^7? (XWRu; X = As, P) were selected as samples to study their catalytic activities towards the solvent‐free oxidation of n‐hexadecane. First of all, the XWRu were deposited on 3‐aminopropyltriethoxysilane‐modified SBA‐15 to prepare solid catalysts, which were characterized using powder X‐ray diffraction, nitrogen adsorption measurements, Fourier transform infrared reflectance spectroscopy and X‐ray photoelectron spectroscopy. Subsequently, their catalytic performances and stabilities were assessed through the oxidation of n‐hexadecane using air as the oxygen source without any additives and solvents, and the influences of the loading amount, catalyst amount, reaction time and reaction temperature on the catalytic activities were investigated. The results indicated the influence of the central heteroatoms X of XWRu on the catalytic activities. Copyright © 2014 John Wiley & Sons, Ltd.     

Electrospray Ionization Based Methods for the Generation of Polynuclear Oxo- and Hydroxo Group 6 Anions in the Gas-Phase

Electrospray ionization (ESI) of the Lindqvist (n-Bu₄N)₂[M₆O₁₉] (M = Mo, W) polyoxometalates provides a straightforward entry for the generation of an assortment of oxo- and hydroxo anions in the gas-phase. In particular, the series of oxo dianions of general formula [(MO₃) _n O]²⁻ (n = 2–6; M = Mo, W), monoanions, namely [(MO₃) _n O]⁻ (n = 1, 2) and [(MO₃) _n ]⁻ (n = 1, 2), and the hydroxo [(MO₃) _n (OH)]⁻ (n = 1–6) species can be readily generated in the gas-phase upon varying the solvent composition as well as the ionisation conditions (typically the U_c cone voltage). Complementary tandem mass experiments (collision induced dissociation and ion–molecule reactions) are also used aimed to investigate the consecutive dissociation of these species and their intrinsic gas-phase reactivity towards methanol. Special emphasis is paid to some of the key factors of these group 6 anions related to the gas-phase activation of methanol, such as molecular composition, open vs closed shell electronic nature and cluster size.     

2‐Methyl‐1,3‐disulfoimidazolium polyoxometalate hybrid catalytic systems as equivalent safer alternatives to concentrated sulfuric acid in nitration of aromatic compounds

Ionic liquid‐derived polyoxometalate salts [mdsim]₃[PM₁₂O₄₀] (where M = W and Mo) of two heteropolyacids H₃PW₁₂O₄₀.nH₂O and H₃PMo₁₂O₄₀.nH₂O were synthesized using 2‐methyl‐1,3‐disulfoimidazolium chloride ([mdsim][Cl]) ionic liquid and the corresponding heteropolyacids. Three equivalents of [mdsim][Cl] were treated with the respective Keggin‐structured heteropolyacids (one equivalent) in aqueous medium at room temperature to afford the water‐stable ionic polyoxometalates as acidic solids. They were completely characterized using spectroscopic and other analytical techniques including thermal analysis and Hammett acidity studies. The inherent Brønsted acidic properties of ─SO₃H group of these polyoxometalate salts were studied for the nitration of aromatic compounds with 69% HNO₃ at normal temperature and 80°C without use of any external concentrated sulfuric acid. These strongly acidic polyoxometalates display good recyclability and efficient reusability.     

Diverse Ligand‐Functionalized Mixed‐Valent Hexamanganese Sandwiched Silicotungstates with Single‐Molecule Magnet Behavior

Under hydrothermal conditions, replacement of the water molecules in the [Mn^III₄Mn^II₂O₄(H₂O)₄]⁸⁺ cluster of mixed‐valent Mn₆ sandwiched silicotungstate [(B‐α‐SiW₉O₃₄)₂Mn^III₄Mn^II₂O₄(H₂O)₄]^12? ( 1 a ) with organic N ligands led to the isolation of five organic–inorganic hybrid, Mn₆‐substituted polyoxometalates (POMs) 2 – 6 . They were all structurally characterized by IR spectroscopy, elemental analysis, thermogravimetric analysis, diffuse‐reflectance spectroscopy, and powder and single‐crystal X‐ray diffraction. Compounds 2 – 6 represent the first series of mixed‐valent {Mn^III₄Mn^II₂O₄(H₂O)_4?n(L)_n} sandwiched POMs covalently functionalized by organic ligands. The preparation of 1 – 6 not only indicates that the double‐cubane {Mn^III₄Mn^II₂O₄(H₂O)_4?n(L)_n} clusters are very stable fragments in both conventional aqueous solution and hydrothermal systems and that organic functionalization of the [Mn^III₄Mn^II₂O₄(H₂O)₄]⁸⁺ cluster by substitution reactions is feasible, but also demonstrates that hydrothermal environments can promote and facilitate the occurrence of this substitution reaction. This work confirms that hydrothermal synthesis is effective for making novel mixed‐valent POMs substituted with transition‐metal (TM) clusters by combining lacunary Keggin precursors with TM cations and tunable organic ligands. Furthermore, magnetic measurements reveal that 3 and 6 exhibit single‐molecule magnet behavior.