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1.
Dalton Trans ; 2020 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-31976497

RESUMO

By changing the stoichiometric ratios, the one-pot reaction of the glycinehydroxamic acid (H2glyha) ligand with copper(ii) and lanthanide(iii) salts in the presence of diamagnetic [Na2{Fe(CN)5(NO)}] led to two series of isostructural complexes, which can be designated as heterotrimetallic dimeric clusters [{LnCu5(glyha)5}{Fe(CN)5(NO)}(H2O)4]2·xNO3·yH2O (x = 2, y = 11 for La (1), x = 2, y = 11 for Pr (2), and x = 2, y = 11 for Nd (3)) and heterotetrametallic coordination polymers [Na{LnCu5(glyha)5}{Fe(CN)5(NO)}2(H2O)x·yH2O]n (x = 6, y = 4 for Sm (4), x = 6, y = 0 for Gd (5), x = 6, y = 4 for Tb (6), x = 5, y = 5 Dy (7), and x = 6, y = 4 for Ho (8)). Each molecular structure contains LnIII[15-metallacrown-5] nodes and diamagnetic [Fe(CN)5(NO)]2- linkers. The resulting products demonstrate diversified structural frameworks due to the radius effect of LnIII ions and different bridging fashions of diamagnetic [Fe(CN)5(NO)]2- linkers. An analysis of magnetic susceptibilities reveals that 7 exhibits ferromagnetic coupling between CuII and DyIII ions and field-induced SMM behavior.

2.
Chemistry ; 26(4): 921-926, 2020 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-31693235

RESUMO

Engineering p-n heterojunctions among metal oxide semiconductors to provide a built-in electric field is an efficient strategy to facilitate the separation of photogenerated electrons and holes and improve their photocatalytic activities. However, the inherent poor conductivity of p-n heterojunctions still limits the charge-transfer step and thus hampers their practical application in photocatalysis. In this work, a nitrogen-doped carbon-coated NiO/TiO2 p-n (NCNT) heterojunction with hierarchical mesoporous sphere morphology was synthesized by in situ pyrolytic decomposition of nickel-titanium complexes. The NiO/TiO2 p-n heterojunction in NCNT was fully characterized by several techniques, supported by theoretical calculations and Mott-Schottky plots. On coating with a thin nitrogen-doped carbon layer, the electron transfer of the obtained p-n heterojunction could be significantly enhanced. On account of the favorable structural features of the p-n heterojunction with nitrogen-doped carbon coating and hierarchical mesoporous structure, NCNT exhibited excellent photocatalytic activity toward various reaction systems, including the hydrogen evolution reaction and the visible-light-induced hydroxylation of phenylboronic acids.

3.
ACS Appl Mater Interfaces ; 12(2): 2390-2399, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31846287

RESUMO

Sodium/Potassium-ion batteries (SIBs/PIBs) have recently received tremendous attention because of their particular features of cost-effectiveness and promising energy density, which hold great potential for large-scale applications. Nevertheless, it still has a common bottleneck issue that is the sluggish kinetics of Na+/K+ intercalation, which raises more rigorous requirement on the electrode candidates regarding the morphology, dimension, and architecture. Herein, we have constructed unique MoSe2-based hybrid nanotubes with wall structures composed of highly disordered MoSe2 layers embedded in phosphorus and nitrogen co-doped carbon matrix (denoted MoSe2⊂PNC-HNTs), by a facile two-step strategy using Se nanorods as the dual-functional template, i.e., shape-directed agent and in situ selenization resources. Benefitting from the combined features of the one-dimensional (1D) hollow interior, hybrid wall structure with high disorder, and the phosphorus and nitrogen co-doping-induced abundant defect sites in the carbon matrix, the MoSe2⊂PNC-HNT anode exhibits high specific capacities of 280 and 262 mA h g-1 over 200 cycles at the current density of 0.1 A g-1 for Na+ and K+ storage, respectively, and achieves remarkable capacity retention rates of 87.0% at 2 A g-1 over 3500 cycles for Na-ion storage and 80.1% at 1 A g-1 after 500 cycles for K-ion storage.

4.
Small ; 15(42): e1902881, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31433124

RESUMO

Research on sodium-ion batteries (SIBs) has recently been revitalized due to the unique features of much lower costs and comparable energy/power density to lithium-ion batteries (LIBs), which holds great potential for grid-level energy storage systems. Transition metal dichalcogenides (TMDCs) are considered as promising anode candidates for SIBs with high theoretical capacity, while their intrinsic low electrical conductivity and large volume expansion upon Na+ intercalation raise the challenging issues of poor cycle stability and inferior rate performance. Herein, the designed formation of hybrid nanoboxes composed of carbon-protected CoSe2 nanoparticles anchored on nitrogen-doped carbon hollow skeletons (denoted as CoSe2 @C∩NC) via a template-assisted refluxing process followed by conventional selenization treatment is reported, which exhibits tremendously enhanced electrochemical performance when applied as the anode for SIBs. Specifically, it can deliver a high reversible specific capacity of 324 mAh g-1 at current density of 0.1 A g-1 after 200 cycles and exhibit outstanding high rate cycling stability at the rate of 5 A g-1 over 2000 cycles. This work provides a rational strategy for the design of advanced hybrid nanostructures as anode candidates for SIBs, which could push forward the development of high energy and low cost energy storage devices.

5.
Chemistry ; 25(62): 14133-14139, 2019 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-31390102

RESUMO

Multicomponent NiTiO3 /A-TiO2 /R-TiO2 photocatalysts coated with nitrogen-doped carbon (N-C/NiTiO3 /A-TiO2 /R-TiO2 ) for efficient H2 production were fabricated by directly pyrolyzing NH2 -MIL-125(Ni/Ti) metal-organic framework microrods. Owing to the synergistic effect of the N-doped carbon coating layer and multicomponent heterojunctions, the H2 production rate of N-C/NiTiO3 /A-TiO2 /R-TiO2 was even higher than that of its Pt-containing counterpart (Pt/NiTiO3 /A-TiO2 /R-TiO2 ). N-C/NiTiO3 /A-TiO2 and N-C/NiTiO3 /R-TiO2 as control photocatalysts were also prepared by simply adjusting the calcination temperature of NH2 -MIL-125(Ni/Ti) in air atmosphere. The H2 production rate followed the order of N-C/NiTiO3 /A-TiO2 /R-TiO2 >N-C/NiTiO3 /A-TiO2 >N-C/NiTiO3 >R-TiO2 , which indicates that the multicomponent heterojunction plays a key role in photocatalytic H2 generation. The mechanism for the influence of the multicomponent heterojunction on photocatalytic activity was investigated in combination with molecular simulations, which showed that N-C/NiTiO3 /A-TiO2 /R-TiO2 has a so-called double type II heterojunction providing a perfect step-by-step migration pathway for effective separation of photogenerated electrons and holes. This work presents a simple and effective method for synthesizing efficient multicomponent photocatalysts.

6.
Inorg Chem ; 57(19): 12347-12353, 2018 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-30230324

RESUMO

Both heteroleptic (phthalocyaninato)(hemiporphyrazinato) and homoleptic bis(hemiporphyrazinato) dysprosium double-decker complexes, Dy[H(Hp)2] (1) and Dy[H(Pc)(Hp)] (2) (H2Pc = metal-free phthalocyanine; H2Hp = metal-free hemiporphyrazine), were designed, synthesized, and structurally characterized. The dysprosium center in both double-deckers are octa-coordinated with a nearly ideal square-antiprismatic coordination geometry, which provides an increased molecular anisotropy for the dysprosium ion and ensures the strengthened magnetic properties of both single-ion magnets (SIMs) in terms of coordination geometry. Magnetic studies reveal that both double-deckers exhibit typical SIM behavior with a spin reversal energy barrier of 80.1 ± 6.3 K for 1 and 57.3 ± 3.8 K for 2 as well as the hysteresis loops emerging at 3 K. In particular, introduction of two Hp ligands with four pyridine nitrogen atoms coordinated with the dysprosium spin center endows Dy[H(Hp)2] (1) with the thus far highest energy barrier among the sandwich-type dysprosium SIMs with N4-macrocyclic ligands, revealing the potential applications of sandwich-type lanthanide complexes with Hp ligands in molecular-based information storage.

7.
Inorg Chem ; 56(19): 11503-11512, 2017 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-28901754

RESUMO

Two triple-decker dinuclear sandwich dysprosium complexes, which are represented as Dy2[Pc(OC5H11)8]2[Cor(FPh)3] (1) and Dy2[Pc(OC5H11)8]2[Cor(ClPh)3] (2), were synthesized and characterized by spectroscopic and electrochemical methods in nonaqueous media. Their electronic structures were also investigated on the basis of TD-DFT calculations. The sandwich triple-decker nature with the molecular conformation of [Pc(OC5H11)8]Dy[Cor(FPh)3]Dy[Pc(OC5H11)8] for compound 1 was unambiguously revealed by single-crystal X-ray diffraction analysis and showed each dyprosium ion to be octacoordinated by the isoindole and pyrrole nitrogen atoms of an outer phthalocyanine ring and the central corrole ring, respectively. In addition, the magnetic properties of both compounds have also been characterized for exploring the functionalities of these types of triple-decker complexes.

8.
Dalton Trans ; 46(38): 13027-13034, 2017 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-28937171

RESUMO

Herein, a new family of LnIII[18-metallacrown-6] compounds with the formula [Fe6O2Ln(tBu-sao)6(OH)(MeO)4(MeOH)(H2O)]·6MeOH [Ln = DyIII (1), TbIII (2), GdIII (3), and YIII (4), tBu-saoH2 = 3,5-di-tert-butylsalicylaldoxime] was synthesized through one-pot reactions using tBu-saoH2, Fe(ClO4)3·6H2O, and Ln(NO3)3·6H2O. The four compounds are isostructural, and the encapsulation of a Ln ion in the ring cavity of 18-metallacrown-6 (18-MC-6) was exhibited for the first time. The structural analysis shows a ship-like 18-MC-6 core with a beset lanthanide ion connecting six ring oxygen atoms (OMC). Magnetic measurements reveal domain antiferromagnetic coupling interactions between metal ions and field-dependent slow magnetic relaxation in 1-3.

9.
Inorg Chem ; 56(5): 2481-2489, 2017 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-28199094

RESUMO

Two novel POM-based inorganic-organic hybrids, [Cu6II(2,2'-bipy)6(Mo6O22)(SiW12O40)]n (1), and {[Cu6II(ppz)6(H2O)5(MoO4)(SiW12O40)]·4H2O}n (2) (2,2'-bipy = 2,2'-bipyridine, Hppz = 3-(pyrid-2-yl)pyrazole), have been constructed from heteropolytungstates and molybdates. Two compounds have been identified by single crystal X-ray diffraction, elemental analysis, and FT-IR. Compound 1 shows a 1D (one-dimensional) chain structure constructed from classical Keggin heteropolytungstate [SiW12O40]4- clusters and [Cu6(2,2'-bipy)6] modified isopolymolybdates [Mo6O22]8-. Compound 2 also represents a 1D chain-like motif built from classical Keggin heteropolytungstate [SiW12O40]4- clusters and [Cu8(ppz)6(H2O)5] modified molybdates MoO42-. Compound 1 represents the first example of POM-based inorganic-organic hybrid with mixed heteropolytungstates and isopolymolybdates. ESI-MS (electrospray ionization mass spectrometry) technique was employed to reveal the species and their evolutions in the hydrothermal reaction, whereby trivacant [SiW9] building block gradually transforms to classical Keggin [SiW12] during assembly process. Furthermore, the electrocatalytic and magnetic properties were discussed in details.

10.
ACS Appl Mater Interfaces ; 8(51): 35163-35171, 2016 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-27977117

RESUMO

The commercial applications of Mn3O4 in lithium ion batteries (LIBs) are greatly restricted because of the low electrical conductivity and poor cycling stability at high current density. To overcome these drawbacks, mesoporous Mn3O4@C networks were designed and synthesized via an improved bake-in-salt method using NaCl as the assistant salt, and without the protection of inert gas. The added NaCl plays a versatile role during the synthetic process, including the heat conducting medium, removable hard template and protective layer. Because of the homogeneous distribution of Mn3O4 nanoparticles within the carbon matrix, the as-prepared Mn3O4@C networks show excellent cycling stability in LIBs. After cycling for 950 times at a current density of 1 A g-1, the discharge capacity of the as-prepared Mn3O4@C networks is determined to be 754.4 mA h g-1, showing superior cycling stability as compared to its counterparts. The valuable and promising method, simple synthetic procedure and excellent cycling stability of the as-prepared Mn3O4@C networks makes it a promising candidate as the potential anode material for LIBs.

11.
Nanoscale Res Lett ; 11(1): 444, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27699715

RESUMO

MnS has been attracting more and more attentions in the fields of lithium ion batteries (LIBs) because of its high energy density and low voltage potential. In this paper, we present a simple method for the preparation of urchin-like γ-MnS microstructures using L-cysteine and MnCl2 · 4H2O as the starting materials. The urchin-like γ-MnS microstructures exhibit excellent cycling stability (823.4 mA h g-1 at a current density of 500 mA g-1, after 1000 cycles). And the discharge voltage is about 0.75 V, making it a good candidate for the application as the anode material in LIBs. SEM, TEM, and XRD were employed to inspect the changes of the active materials during the electrochemical process, which clearly indicate that the structural pulverization and reformation of the γ-MnS microstructures play important roles for the maintenance of the electrochemical performance during the charge/discharge process.

12.
Inorg Chem ; 55(17): 9006-11, 2016 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-27548500

RESUMO

A planar hexanuclear cobalt ring was clamped by two bivacant α1-[PW10O37](9-) with the assistance of the pyridazine bridges to form a novel sandwiched Co(II)-polyoxometalate cluster compound, [Na(H2O)6][Co3(OH) (pydz)4(H2O)7][Co6(PW10O37)2(pydz)4(H2O)6]·43H2O (1; pydz = pyridazine).This cluster was identified by X-ray single-crystal diffraction, elemental analysis, Fourier transform IR and UV-visible spectroscopies, and cyclic voltammetry (CV). Structural analysis reveals that 1 comprises a hexahydrated sodium, a trinuclear [Co3(OH) (pydz)4(H2O)7](5+) cationic cluster, and an anionic [Co6(PW10O37)2(pydz)4(H2O)6](6-) sandwiched cluster, thus giving an intrinsical intercluster compound. The isolation of such cluster was dependent on the in situ transformation of trivacant [α-P2W15O56](12-) to α1-[PW10O37](9-) under the hydrothermal condition. The CV shows reversible multielectron waves from the redox of W(VI) in 1. Cluster 1 exhibits remarkable electrocatalytic activity toward the reduction of nitrite. Magnetism studies indicated a weak anti-ferromagnetic exchange interaction between Co(II) ions within 1.

13.
Dalton Trans ; 45(20): 8404-11, 2016 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-27108482

RESUMO

Modified classical trivacant Wells-Dawson α-[P2W15O56](12-) and the assembly of related sandwiched transition metal clusters are of interest, but surprisingly few reports of these materials exist because of the sensitivity of α-[P2W15O56](12-) to the assembly environment. Herein, we describe the pH-controlled assembly of two novel Dawson-sandwiched clusters, (H2bpz)6[Co2(P2W16O57)2]·22H2O (1, bpz = 3,3',5,5'-tetramethyl-4,4'-bipyrazole) and (H2bpz)6[Co3H2(P2W16O57)(P2W15O56)(H2O)]·12H2O (2), involving the in situ transformation of α-[P2W15O56](12-). Both clusters were characterized by X-ray single-crystal diffraction, FT-IR spectroscopy, UV-Visible spectroscopy, thermogravimetric analysis, powder X-ray diffraction, and elemental analyses. X-ray crystallography showed that both heteropolytungstates become divacant α-[P2W16O57](8-) and symmetrically encapsulate two edge-shared CoO6 octahedra in the interior in 1, while only one divacant α-[P2W16O57](8-) is observed in 2, which combined with another trivacant α-[P2W15O56](12-) to asymmetrically clamp three edge-shared CoO6 octahedra. The α-[P2W16O57](8-) heteropolytungstate should be generated in situ from α-[P2W15O56](12-)via self-decomposition equilibria in solution. Their electrochemical behaviors reveal characteristic multi-electron redox processes related to W(VI) centers. The electrocatalytic reduction performances toward nitrite, hydrogen peroxide, chlorate, bromate and iodate were fully measured and discussed; among these species, both clusters exhibit the best electrocatalytic activity towards the reduction of bromate. Magnetic measurements indicate weak ferromagnetic exchange interactions between Co atoms sandwiched by vacant polyoxometalates.

14.
Nanoscale Res Lett ; 11(1): 126, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26951126

RESUMO

In this report, a novel photocatalyst based on Bi2WO6/Ag2S heterostructures was prepared by a 3-mercaptopropionic acid (MPA)-assisted route at room temperature. Compared to bare Bi2WO6 and Ag2S nanoparticles, the as-formed Bi2WO6/Ag2S heterostructures exhibit enhanced photocatalytic activity for the degradation of rhodamine B (Rh B) under visible-light irradiation. This kind of enhancement in the photocatalytic activity is considered to be the synergistic effects of both the effective electron-hole separation and expansion of the light-absorption range. The pH of the solution is of vital importance to the photocatalytic activity of the as-formed Bi2WO6/Ag2S heterostructures. Under low pH value, the photosensitization process is suppressed, while under higher pH value, the photosensitization process is favored. The mechanism of the photocatalytic process was proposed by the active-species-trapping experiments, indicating that the photogenerated holes (h(+)) play a crucial role in the degradation of Rh B under visible light. The enhanced photocatalytic performance of this heterostructure makes it a promising material for the treatment of dye-containing wastewater.

15.
J Colloid Interface Sci ; 466: 388-99, 2016 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-26752434

RESUMO

Highly-efficient photocatalyst based on Bi2WO6/SnS heterostructure was prepared via a surface functionalization method using 3-mercaptopropionic (MPA) as the surface functionalizing agent. Compared to bare Bi2WO6 and SnS nanoparticles, the as-formed Bi2WO6/SnS heterostructure exhibits enhanced photocatalytic activity for the degradation of Rhodamine B (Rh B). Photoluminescence and photocurrent measurements demonstrate that the enhanced photocatalytic activity during the photocatalytic process is closely related to the enhanced electron-hole separation efficiency. The photocatalytic activity of the as-formed Bi2WO6/SnS heterostructure can be perfectly remained even after being used for five times, showing excellent durability during the photocatalytic process. The influence of pH and inorganic ions are systematically investigated. And the optimum pH for the photocatalytic process is determined to be 6. The addition of chloride ion will exert negative effect on the photodegradation process of Rh B. The mechanism of photodegradation process was investigated by exploring the quenching effects of different scavengers and the results suggest that the reactive holes play the major role in the photodegradation process of Rh B.

16.
Chemistry ; 21(41): 14478-85, 2015 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-26295925

RESUMO

Mixed 3d-4f 12-azametallacrown-4 complexes, [Mn2 Ln2 (OH)2 (hppt)4 (OAc)2 (DMF)2 ]⋅2 DMF⋅H2 O [Ln=Dy (1), Er (2), Yb (3), Tb (4) and Y (5), H2 hppt=3-(2-hydroxyphenyl)-5-(pyrazin-2-yl)-1,2,4-triazole)], were synthesized by reactions of H2 hppt with Mn(OAc)2 ⋅4 H2 O and Ln(NO3 )3 ⋅6 H2 O. This is the first 3d-4f azametallacrown family to incorporate Ln ions into the ring sets. These isostructural complexes exhibit alternating arrangements of two Mn and two Ln ions in the rings with each pair of metal centers bound by an NN group and µ2 -O bridging. Magnetic measurements revealed dominant antiferromagnetic interactions between metal centers, and frequency-dependent out-of-phase (${\chi {^\prime}{^\prime}_{\rm{M}} }$) signals below 4 K suggest slow relaxation of magnetization.

17.
Sci Rep ; 5: 8838, 2015 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-25744587

RESUMO

Two tetrakis(phthalocyaninato) dysprosium(III)-cadmium(II) single-molecule magnets (SMMs) with different extent of phthalocyanine peripheral substitution and therefore different coordination geometry for the Dy ions were revealed to exhibit different SMM behavior, providing an easy way to tuning and controlling the molecular structure and in turn the magnetic properties of tetrakis(tetrapyrrole) lanthanide SMMs through simple tetrapyrrole peripheral substitution.

18.
Dalton Trans ; 44(14): 6620-9, 2015 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-25758136

RESUMO

An unusual solvent effect on the synthesis of five manganese complexes [Mn2(L1)2(Py)4](), [Mn2(L1)2(DMSO)4](), [Mn4(L2)4(OH)4](), [Mn4(L3)2(DMSO)7(H2O)](), and [Mn6O2(L4)4(OAc)2(OMe)2(DMSO)4]·MeOH] (), (H3L1 = 5-(2-oxyphenyl)-pyrazole-3-carboxylic acid; H2L2 = 5-(2-oxyphenyl)-pyrazole-3-carboxylic acid amide; H4L3 = di-[5-(2-oxyphenyl)-pyrazole]-3-hydroxamic ether; and H2L4 = 5-(2-oxyphenyl)-pyrazole-3-carboxylic acid methyl ester) has been reported. Five complexes have been characterized by X-ray single crystal diffraction, IR, element analysis, thermogravimetric analysis and UV-vis spectra. The analysis reveals that complexes and are isostructural with a bimetallic six-membered ring and L1 from the decomposition of the original H4ppha (H4ppha = 5-(2-hydroxyphenyl)-pyrazole-3-hydroxamic acid) ligand. Complexes and are two tetranuclear clusters, and possesses an aza12-metallacrown-4 core with L2 from the amide functionalization of the decomposition L1; while represents a novel linear [Mn4N8O2] core with L3 from the condensation of L1 and H4ppha. Complex is the first Mn6 cluster linked by two stacked, off-set 8-azametallacrown-3 subunits with [M-N-N-M-N-N-M-O] connectivity, and L4 derived from the esterification of L1. The magnetic behaviour of complexes show the dominant antiferromagnetic interactions between metal centers, whereas complex further reveals the coexistence of antiferromagnetic and ferromagnetic interactions, and slow magnetic relaxation at T < 6 K with S = 4 ground state, as well as field induced magnetization saturation.

19.
J Colloid Interface Sci ; 432: 236-45, 2014 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-25086718

RESUMO

Controlled synthesis of well-shaped nanocrystals is of significant importance to understand the surface-related properties. Herein, hierarchical Bi2WO6 particles with different morphologies, such as flower-like and pancake-like morphologies were selectively prepared using a simple fluoride ion-assisted hydrothermal process. Morphological modulation of the samples could be easily realized by controlling the initial amount of NH4F. The effect of NH4F as well as the formation mechanism of these Bi2WO6 hierarchical structures were systematically investigated. The morphological control of the final products are proved to be a kinetic control of the reaction, which is closely related to the concentration of fluoride ion in the solution. The as-obtained hierarchical Bi2WO6 particles exhibit different visible-light-driven photo-catalytic activities for the degradation of Rhodamine-B (RhB). The differences in photo-catalytic activities among the as-obtained samples are associated the surface adsorption properties, which result from the synthetic conditions.

20.
Dalton Trans ; 42(43): 15355-60, 2013 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-24005576

RESUMO

Reaction between Schiff-base ligand and half-sandwich complex M(Pc)(acac) led to the isolation of new sandwich-type mixed (phthalocyaninato)(Schiff-base) di-lanthanide compounds M2(Pc)2(L)H2O (M = Dy, Gd) (1, 2) [H2Pc = metal free phthalocyanine, Hacac = acetylacetone, H2L = N,N'-bis(3-methyloxysalicylidene)benzene-1,2-diamine] with the triple-decker molecular structure clearly revealed by single crystal X-ray diffraction analysis. For the comparative studies, sandwich triple-decker analogues with pure Schiff-base ligand M2(L)3H2O (M = Dy, Gd) (3, 4) were also prepared. Dynamic magnetic measurement result reveals the single-molecule magnet (SMM) nature of the di-dysprosium derivative 1, while the static magnetic investigation over both pure and the diamagnetic diluted samples of this compound discloses the interionic ferromagnetic coupling between the two dysprosium ions, which in turn effectively suppresses the QTM and enhances the energy barrier of this SMM. Nevertheless, comparative studies over the static magnetic properties of the di-dysprosium triple-decker complexes 1 and 3 indicate the stronger magnetic coupling between the two lanthanide ions in mixed (phthalocyaninato)(Schiff-base) species than in the pure Schiff-base triple-decker analogue, suggesting the special coordination sphere around the dysprosium ions in the former compound over the latter one on the more intense inter-ionic ferromagnetic coupling. As a very small step towards understanding the structure-property relationship, the present result will be surely helpful for the design and synthesis of the multinuclear lanthanide-based SMMs with good properties.

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