1
|
Precise Modulation of CO 2 Sorption in Ti 8Ce 2-Oxo Clusters: Elucidating Lewis Acidity of the Ce Metal Sites and Structural Flexibility. J Am Chem Soc 2024. [PMID: 38795041 DOI: 10.1021/jacs.4c01092] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/27/2024]
Abstract
Investigating the structure-property correlation in porous materials is a fundamental and consistent focus in various scientific domains, especially within sorption research. Metal oxide clusters with capping ligands, characterized by intrinsic cavities formed through specific solid-state packing, demonstrate significant potential as versatile platforms for sorption investigations due to their precisely tunable atomic structures and inherent long-range order. This study presents a series of Ti8Ce2-oxo clusters with subtle variations in coordinated linkers and explores their sorption behavior. Notably, Ti8Ce2-BA (BA denotes benzoic acid) manifests a distinctive two-step profile during the CO2 adsorption, accompanied by a hysteresis loop. This observation marks a new instance within the metal oxide cluster field. Of intrigue, the presence of unsaturated Ce(IV) sites was found to be correlated with the stepped sorption property. Moreover, the introduction of an electrophilic fluorine atom, positioned ortho or para to the benzoic acid, facilitated precise control over gate pressure and stepped sorption quantities. Advanced in situ techniques systematically unraveled the underlying mechanism behind this unique sorption behavior. The findings elucidate that robust Lewis base-acid interactions are established between the CO2 molecules and Ce ions, consequently altering the conformation of coordinated linkers. Conversely, the F atoms primarily contribute to gate pressure variation by influencing the Lewis acidity of the Ce sites. This research advances the understanding in fabricating metal-oxo clusters with structural flexibility and provides profound insights into their host-guest interaction motifs. These insights hold substantial promise across diverse fields and offer valuable guidance for future adsorbent designs grounded in fundamental theories of structure-property relationships.
Collapse
|
2
|
A Cubic Tinkertoy-like Heterometallic Cluster with a Record Magnetocaloric Effect. J Am Chem Soc 2024; 146:9506-9511. [PMID: 38557065 DOI: 10.1021/jacs.4c01372] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/04/2024]
Abstract
Clusters showing a giant magnetocaloric effect (MCE) are of interest as molecular coolants for magnetic refrigeration. Herein, we report two heterometallic clusters, denoted as Gd152Ni14@Cl24 and Sm152Ni8, just to highlight their inorganic core motifs, obtained by ligand-controlled co-hydrolysis of Ni2+ and Ln3+ (Ln = Gd, Sm) in the presence of N-(2-hydroxyethyl)iminodiacetic acid (H2HEIDA). Both clusters display fascinating cubic Tinkertoy-like structures, with the core motifs being built of multiple metallic shells of Platonic and Archimedean polyhedra. The isothermal magnetic entropy change─a direct measurement of MCE─was determined to be 52.65 J·kg-1·K-1 at 2.5 K and 7.0 T for the Gd-containing cluster; this value is the highest known for any molecular clusters so far reported.
Collapse
|
3
|
Tuning Electrocatalytic Water Oxidation Activity: Insights from the Active-Site Distance in LnCu 6 Clusters. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2024:e2401044. [PMID: 38516941 DOI: 10.1002/smll.202401044] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/08/2024] [Revised: 03/12/2024] [Indexed: 03/23/2024]
Abstract
Atomically precise metal clusters serve as a unique model for unraveling the intricate mechanism of the catalytic reaction and exploring the complex relationship between structure and activity. Herein, three series of water-soluble heterometallic clusters LnCu6, abbreviated as LnCu6-AC (Ln = La, Nd, Gd, Er, Yb; HAC = acetic acid), LnCu6-IM (Ln = La and Nd; IM = Imidazole), and LnCu6-IDA (Ln = Nd; H2IDA = Iminodiacetic acid) are presented, each featuring a uniform metallic core stabilized by distinct protected ligands. Crystal structure analysis reveals a triangular prism topology formed by six Cu2+ ions around one Ln3+ ion in LnCu6, with variations in Cu···Cu distances attributed to different ligands. Electrocatalytic oxygen evolution reaction (OER) shows that these different LnCu6 clusters exhibit different OER activities with remarkable turnover frequency of 135 s-1 for NdCu6-AC, 79 s-1 for NdCu6-IM and 32 s-1 for NdCu6-IDA. Structural analysis and Density Functional Theory (DFT) calculations underscore the correlation between shorter Cu···Cu distances and improves OER catalytic activity, emphasizing the pivotal role of active-site distance in regulating electrocatalytic OER activities. These results provide valuable insights into the OER mechanism and contribute to the design of efficient homogeneous OER electrocatalysts.
Collapse
|
4
|
Different anion (NO 3- and OAc -)-controlled construction of dysprosium clusters with different shapes. Dalton Trans 2024; 53:5665-5675. [PMID: 38445301 DOI: 10.1039/d3dt03314g] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/07/2024]
Abstract
The complex hydrolysis process and strong uncertainty of self-assembly rules have led to the precise synthesis of lanthanide clusters still being in the "blind-box" stage and simplifying the self-assembly process and developing reliable regulation strategies have attracted widespread attention. Herein, different anions are used to induce the construction of a series of dysprosium clusters with different shapes and connections. When the selected anion is NO3-, it blocks the coordination of metal sites around the cluster through the terminal group coordination mode, thereby controlling the growth of the cluster. When NO3- was changed to OAc-, OAc- adopted a bridging mode to induce modular units to build dysprosium clusters through an annular growth mechanism. Specifically, we selected 2-amino-6-methoxybenzoic acid, 2-hydroxybenzaldehyde, and Dy(NO3)3·6H2O to react under solvothermal conditions to obtain a pentanuclear dysprosium cluster (1). The five Dy(III) ions in 1 are distributed in upper and lower planes and are formed by the tight connection of nitrogen and oxygen atoms, and μ3-OH- bridges on the ligand. Next, octa-nuclear dysprosium cluster (2) were obtained by only regulating ligand substituents. The eight Dy(III) ions in 2 are tightly connected through ligand oxygen atoms, μ2-OH-, and μ3-OH- bridges, forming an elliptical {Dy/O} cluster core. Furthermore, only by changing NO3- to OAc-, a wheel-shaped tetradeca-nuclear dysprosium cluster (3) was obtained. Cluster 3 is composed of OAc- bridged multiple template Dy3L3 units and pulling of these template units connected by an annular growth mechanism forms a wheel-shaped cluster. The angle of the coordination site on NO3- is ∠ONO = 115°, which leads to the further extension of the metal sites on the periphery of clusters 1 and 2 through the terminal group coordination mode, thereby regulating the structural connection of the clusters. However, the angle of the coordination site on OAc- is ∠OCO = 128°, and a slightly increased angle leads to the formation of a ring-shaped cluster 3 by connecting the template units through bridging. This is a rare example of the controllable construction of lanthanide clusters with different shapes induced by the regulation of different anions, which provides a new method for the precise construction of lanthanide clusters with special shapes.
Collapse
|
5
|
Self-Assembly of Lanthanide-Aluminum Cluster-Organic Frameworks with Magnetocaloric Effect and Luminescence. Inorg Chem 2024; 63:613-620. [PMID: 38102774 DOI: 10.1021/acs.inorgchem.3c03504] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2023]
Abstract
The self-assembly of the lanthanide metal-organic frameworks presents a formidable challenge but profound significance. Compared with the metal-organic frameworks based on 4f-3d ions, the chemistry of 4f-3p metal-organic frameworks has not been fully explored so far. In this study, two lanthanide-aluminum-based clusters [Ln6Al(IN)10(μ3-OH)5(μ3-O)3(H2O)8]·xH2O (x = 2, Ln = Gd, abbreviated as Gd6Al; x = 2.5, Ln = Eu, abbreviated as Eu6Al; HIN = isonicotinic acid) have been meticulously designed and obtained by hydrothermal reaction at low pH. The crystallographic study revealed that both Gd6Al and Eu6Al clusters exhibit an unprecedented sandwiched metal-organic framework holding a highly ordered honeycomb network. To our knowledge, it is the first case of Ln-Al-based cluster-organic frameworks. Furthermore, magnetic investigation of Gd6Al manifests a decent magnetic entropy change of -ΔSmmax = 28.8 J kg-1 K-1 at 2 K for ΔH = 7.0 T. Significantly, the introduction of AlIII ions into the lanthanide metal-organic frameworks displays excellent solid-state luminescent capability with a lifetime of 371.6 μs and quantum yield of 6.64%. The construction and investigation of these two Ln-Al clusters represent great progress in the 4f-3p metal-organic framework.
Collapse
|
6
|
Synthesis, structures and magnetic studies of hexanuclear lanthanide complexes: SMM behavior of the Dy III analogue and MCE properties of the Gd III analogue. Dalton Trans 2023; 52:10594-10608. [PMID: 37462111 DOI: 10.1039/d3dt01489d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/02/2023]
Abstract
The synthesis, structure and magnetic properties of homometallic hexanuclear lanthanide complexes [Ln6(HL)4(tfa)4(S)2]·2NO3·x H2O·yMeOH (1, Ln = Gd, S = MeOH, x = 0, y = 0; 2, Ln = Tb, S = H2O, x = 2, y = 2; 3, Ln = Dy, S = MeOH, x = 0, y = 2; 4, Ln = Er, S = MeOH, x = 0, y = 2). [(H4L) = 6-((bis(2-hydroxyethyl)amino)-N'-(2-hydroxybenzylidene)picolinohydrazide) (tfa = trifloroacetylacetone)] are reported. These hexanuclear assemblies are made up of two trinuclear triangular sub-units linked through the oxygen atoms of two phenoxide bridging groups in a corner sharing arrangement. Magnetic studies reveal that 1 displays a magnetocaloric effect with a maximum value of -ΔSm = 21.03 J kg-1 K-1 at T = 3 K and under an applied field change ΔB = 5 T. Complex 3 shows slow relaxation of magnetization even under zero applied field although a clear maximum in the ac susceptibility plots cannot be seen. However, under an optimal applied field of 0.2 T, clear maxima are observed in the out-of-phase (χ''M) component of the ac susceptibility in the temperature range 3.5 K (2 kHz) to 10.5 K (10 kHz). The temperature dependence of the relaxation times could be fitted to the sum of Orbach, Raman and QTM relaxation processes affording the following parameters: τo = 3.4(9) × 10-8 s, Ueff = 94(2) K, BRaman = 16.43(1) K-n s-1, n = 3.2(3) and τQTM = 0.0044(3) s. 4, under an applied magnetic field of 0.2 T, shows slow relaxation of magnetization through a thermally activated Orbach process with Ueff = 18.2(9) K and τo = 3.5(3) × 10-8 s.
Collapse
|
7
|
Accurate binding of porous aluminum molecular ring catalysts with the substrate. Chem Sci 2023; 14:5396-5404. [PMID: 37234899 PMCID: PMC10208054 DOI: 10.1039/d3sc01260c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2023] [Accepted: 03/30/2023] [Indexed: 05/28/2023] Open
Abstract
Metal molecular rings are a class of compounds with aesthetically pleasing symmetry and fundamentally useful properties. The reported work generally focuses on the ring center cavity, and there is little known about those on the ring waist. Herein, we report the discovery of porous aluminum molecular rings and their performance and contribution to the cyanosilylation reaction. We develop a facile ligand induced aggregation and solvent regulation strategy towards AlOC-58NC and AlOC-59NT with high purity, high yield (75% and 70%, respectively) and gram-level scale-up. These molecular rings exhibit a "two-tier" pore feature involving the general central cavity and newly observed equatorial semi-open cavities. AlOC-59NT with two types of one-dimensional channels showed good catalytic activity. The interaction of the aluminum molecular ring catalyst with the substrate has been crystallographically characterized and theoretically confirmed, showing a ring adaptability process that involves the capture and binding of the substrate. This work provides new ideas for the assembly of porous metal molecular rings and to understand the overall reaction pathway involving aldehydes and is expected to inspire the design of low-cost catalysts through structural modifications.
Collapse
|
8
|
Regulating Activity and Selectivity of Photocatalytic CO 2 Reduction on Cobalt by Rare Earth Compounds. ACS APPLIED MATERIALS & INTERFACES 2023; 15:16621-16630. [PMID: 36949018 DOI: 10.1021/acsami.2c20402] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/18/2023]
Abstract
Cobalt-based catalysts are ideal for CO2 reduction reaction (CO2RR) due to the strong binding and efficient activation of CO2 molecules on cobalt. However, cobalt-based catalysts also show low free energy of hydrogen evolution reaction (HER), making HER competitive with CO2RR. Therefore, how to improve the product selectivity of CO2RR while maintaining the catalytic efficiency is a great challenge. Here, this work demonstrates the critical roles of the rare earth (RE) compounds (Er2O3 and ErF3) in regulating the activity and selectivity of CO2RR on cobalt. It is found that the RE compounds not only promote charge transfer but also mediate the reaction paths of CO2RR and HER. Density functional theory calculations verify that the RE compounds lower the energy barrier of *CO → CO conversion. On the other hand, the RE compounds increase the free energy of HER, which leads to the suppression of HER. As a result, the RE compounds (Er2O3 and ErF3) improve the CO selectivity of cobalt from 48.8 to 69.6%, as well as significantly increase the turnover number by a factor of over 10.
Collapse
|
9
|
Heterometallic 3d-4f Alkoxide Precursors for the Synthesis of Binary Oxide Nanomaterials. Inorg Chem 2023; 62:2197-2212. [PMID: 36696546 PMCID: PMC9906784 DOI: 10.1021/acs.inorgchem.2c03872] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
In this study, a new method for the synthesis of heterometallic 3d-4f alkoxides by the direct reaction of metallic lanthanides (La, Pr, Nd, Gd) with MCl2 (M = Mn, Ni, Co) in 2-methoxyethanol was developed. The method was applied to the synthesis of the heterometallic oxo-alkoxide clusters [Ln4Mn2(μ6-O)(μ3-OR)8(HOR)xCl6] (Ln = La (1), Nd (2), Gd (3); x = 0, 2, 4); [Pr4M2(μ6-O)(μ3-OR)8(HOR)xCl6] (M = Co (4), Ni (5); x = 2, 4); and [Ln4Mn2(μ3-OH)2(μ3-OR)4(μ-OR)4(μ-Cl)2(HOR)4Cl6] (Ln = La (11) and Pr (12)). Mechanistic investigation led to the isolation of the homo- and heterometallic intermediates [Pr(μ-OR)(μ-Cl)(HOR)Cl]n (6), [Co4(μ3-OR)4(HOR)4Cl4] (7), [Ni4(μ3-OR)4(HOEt)4Cl4] (8), [Mn4(μ3-OR)4(HOR)2(HOEt)2Cl4] (9), and [Nd(HOR)4Cl][CoCl4] (10). In the presence of an external M(II) source at 1100 °C, 1-4 and 12 were selectively converted into binary metal oxide nanomaterials with trigonal or orthorhombic perovskite structures, i.e., LaMnO3, GdMnO3, NdMnO3, Pr0.9MnO3, and PrCoO3. Compound 5 decomposed into a mixture of homo- and heterometallic oxides. The method presented provides a valuable platform for the preparation of advanced heterometallic oxide materials with promising magnetic, luminescence, and/or catalytic applications.
Collapse
|
10
|
Abstract
Metal-containing clusters have attracted increasing attention over the past 2-3 decades. This intense interest can be attributed to the fact that these discrete metal aggregates, whose atomically precise structures are resolved by single-crystal X-ray diffraction (SCXRD), often possess intriguing geometrical features (high symmetry, aesthetically pleasing shapes and architectures) and fascinating physical properties, providing invaluable opportunities for the intersection of different disciplines including chemistry, physics, mathematical geometry and materials science. In this review, we attempt to reinterpret and connect these fascinating clusters from the perspective of Platonic and Archimedean solid characteristics, focusing on highly symmetrical and complex metal-containing (metal = Al, Ti, V, Mo, W, U, Mn, Fe, Co, Ni, Pd, Pt, Cu, Ag, Au, lanthanoids (Ln), and actinoids) high-nuclearity clusters, including metal-oxo/hydroxide/chalcogenide clusters and metal clusters (with metal-metal binding) protected by surface organic ligands, such as thiolate, phosphine, alkynyl, carbonyl and nitrogen/oxygen donor ligands. Furthermore, we present the symmetrical beauty of metal cluster structures and the geometrical similarity of different types of clusters and provide a large number of examples to show how to accurately describe the metal clusters from the perspective of highly symmetrical polyhedra. Finally, knowledge and further insights into the design and synthesis of unknown metal clusters are put forward by summarizing these "star" molecules.
Collapse
|
11
|
Aminopolyol-Dependent Assembly of Heterometallic Lanthanide–Iron–Oxo Clusters. Inorg Chem 2022; 61:20365-20372. [DOI: 10.1021/acs.inorgchem.2c03007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
|
12
|
Mixed-lanthanide clusters: A bridging approach that permits the design of molecular magnetic materials by introducing heavy lanthanides into the 3d-light lanthanide clusters without breaking structural integrity. Polyhedron 2022. [DOI: 10.1016/j.poly.2022.116088] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
|
13
|
The syntheses, structures and magnetic properties of coordination clusters: {M20} (M = CoII, NiII) with a distorted hexahedral topology. J Mol Struct 2022. [DOI: 10.1016/j.molstruc.2022.133297] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
|
14
|
Synthesis, crystal structure and magnetic properties of mer-tricyanidoiron(III) precursor-based 1D heterobimetallic complexes. ZEITSCHRIFT FUR NATURFORSCHUNG SECTION B-A JOURNAL OF CHEMICAL SCIENCES 2022. [DOI: 10.1515/znb-2022-0097] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Abstract
Three new cyanide-bridged heterometallic complexes {{[Cu(S,S-Chxn)2][Fe(bbp)(CN)3]}2·2 H2O}
n
(1), {{[Cu(R,R-Chxn)2][Fe(bbp)(CN)3]}2·2 H2O}
n
(2) and {{[Cu(Cycam)][Fe(bbp)(CN)3]}·CH3OH·2 H2O}
n
(3) (bbp = bis(2-benzimidazolyl)pyridine dianion, Chxn = 1,2-diaminocyclo hexane, cyclam = 1,4,8,11-tetraazacyclodecane) have been assembled from the rarely used mer-tricyanidoiron(III) building block [PPh4]2[Fe(bbp)(CN)3] and three copper(II) compounds. The complexes have been characterized by elemental analysis, IR spectroscopy and single crystal X-ray diffraction. For the chiral enantiomers 1 and 2, the circular dichroism (CD) spectrum was also investigated. X-ray structural analyses revealed that the structures of the cyanide-bridged Fe-Cu complexes 1 and 2 are characterized by two crystallographically independent but structurally very similar homochiral neutral chains, each consisting of the repeating units {[Cu(S,S-Chxn)2][Fe(bbp)(CN)3]} (1) or {[Cu(R,R-Chxn)2][Fe(bbp)(CN)3]} (2). The crystal structure of 3 likewise is build up of chains consisting of {[Cu(Cyclam)][Fe(bbp)(CN)3]} building blocks. The temperature-dependent magnetic susceptibility and field dependent magnetization of the complexes showed antiferromagnetic interactions in complex 1 between the Fe(III) and Cu(II) ions, while complex 3 is ferromagnetic, indicating that the magnetic coupling through cyanide linkage is very sensitive to the structure parameters around the paramagnetic metal ions. These results have been further confirmed by fitting of the experimental data using a uniform chain model, leading to the coupling constants J = −6.35 cm−1, g = 2.08, R = 4.42 × 10−4 and J = 1.24 cm−1, g = 2.09, R = ∑(χ
obsd
T − χ
cald
T)2/∑(χ
obsd
T)2 = 4.67 × 10−4 for complexes 1 and 3, respectively.
Collapse
|
15
|
Rare-Earth Single-Atom Catalysts: A New Frontier in Photo/Electrocatalysis. SMALL METHODS 2022; 6:e2200413. [PMID: 35751459 DOI: 10.1002/smtd.202200413] [Citation(s) in RCA: 18] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/01/2022] [Revised: 05/29/2022] [Indexed: 06/15/2023]
Abstract
Single-atom catalysts (SACs) provide well-defined active sites with 100% atom utilization, and can be prepared using a wide range of support materials. Therefore, they are attracting global attention, especially in the fields of energy conversion and storage. To date, research has focused on transition-metal and precious-metal-based SACs. More recently, rare-earth (RE)-based SACs have emerged as a new frontier in photo/electrocatalysis owing to their unique electronic structure arising from the spin-orbit coupling of the 4f and valence orbitals, unsaturated coordination environment, and unique behavior as charge-transport bridges. However, a systematic review on the role of the RE active sites, catalytic mechanisms, and synthetic methods for RE SACs is lacking. Therefore, in this review, the latest developments in RE SACs having applications in photo/electrocatalysis are summarized and discussed. First, the theoretical advantages of RE SACs for photo/electrocatalysis are briefly introduced, focusing on the roles of the 4f orbitals and coupled energy levels. In addition, the most recent research progress on RE SACs is summarized for several important photo/electrocatalytic reactions and the corresponding catalytic mechanisms are discussed. Further, the synthetic strategies for the production of RE SACs are reported. Finally, challenges for the development of RE SACs are highlighted, along with future research directions and perspectives.
Collapse
|
16
|
Abstract
The magnetocaloriceffect is considered as an energy-efficient and environmentally friendly technique which can take cooling technology to the next level. Apart from its commercial application at room temperature, magnetic refrigeration is an up-and-coming solution for the cryogenic regime, especially as an alternative to He3 systems. Molecular magnets reveal advantageous features for ultra-low cooling which are competitive with intermetallic and lanthanide alloys. Here, we present a guide to the current status of magnetocaloric effect research of molecular magnets with a theoretical background focused on the inverse magnetocaloric effect and an overview of recent results and developments, including the rotating magnetocaloric effect.
Collapse
|
17
|
Abstract
Magnetic refrigerants with a large magnetocaloric effect (MCE) in a wide temperature range and low magnetic ordering temperature (To) in the sub-kelvin temperature region are not only crucial for adiabatic demagnetization refrigeration but also open up a broader parameter space for the optimal design of adiabatic demagnetization refrigerators. However, such magnetic refrigerants are extremely rare because they require magnetic materials to simultaneously satisfy three conditions: low To, weak magnetic interaction, and high magnetic density. Here, we report the syntheses, heat capacities, and magnetic properties of Gd(OH)3-xFx (1: x = 1, 2: x ≈ 1.5, and 3: x = 2), demonstrating for the first time that the introduction of fluoride anions into antiferromagnetic Gd(OH)3 can effectively regulate its To. Significantly, 3 not only has a To of 0.5 K but also exhibits a large MCE in the temperature range from 0.5 to 4 K, representing the best magnetic refrigerant reported to date in the temperature range of 0.5-4 K from the viewpoint of the MCE.
Collapse
|
18
|
Two 1D Anderson-Type Polyoxometalate-Based Metal-Organic Complexes as Bifunctional Heterogeneous Catalysts for CO 2 Photoreduction and Sulfur Oxidation. Inorg Chem 2022; 61:11775-11786. [PMID: 35858285 DOI: 10.1021/acs.inorgchem.2c01497] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Sulfur oxides from the combustion of petrol and excessive emissions of carbon dioxide (CO2) are currently the main causes of environmental pollution. Considerable interest has been paid to solving the challenge, and catalytic reactions seem to be the desired choice. Due to the high density of Lewis acid active sites, polyoxometalates are considered to be the ideal choice for these catalytic reactions. Herein, two captivating polyoxometalate-based metal-organic complexes, formulated as [Co(H2O)2DABT]2[CrMo6(OH)5O19] ({Co-CrMo6}) and [Zn(H2O)2DABT]2[CrMo6(OH)5O19] ({Zn-CrMo6}) (DABT = 3,3'-diamino-5,5'-bis(1H-1,2,4-triazole)) were successfully obtained under hydrothermal conditions. The structural analysis demonstrates that {Co-CrMo6} and {Zn-CrMo6} are isostructural with two different transition metal (Co/Zn) ions based on quadridentate Anderson-type [CrMo6(OH)5O19]4- polyanions. A fan-shaped unit of {Co-CrMo6}/{Zn-CrMo6} is linked to generate a one-dimensional (1D) ladder-like structure. Intriguingly, benefitting from rich Co centers with a suitable energy band structure, {Co-CrMo6} displays better photocatalytic activity than {Zn-CrMo6} for converting CO2 into CO, endowing the CO formation of 1935.3 μmol g-1 h-1 with high selectivity. Meanwhile, {Co-CrMo6} also exhibits a satisfactory removal rate of 99% for oxidizing dibenzothiophene at 50 °C, which suggests that {Co-CrMo6} may be utilized as a potential dual functional material with immense prospects in photocatalytic CO2 reduction and sulfur oxidation for the first time.
Collapse
|
19
|
Recent advances of functional heterometallic-organic framework (HMOF) materials: Design strategies and applications. Coord Chem Rev 2022. [DOI: 10.1016/j.ccr.2022.214521] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
|
20
|
Largest 3d-4f 196-nuclear Gd158Co38 clusters with excellent magnetic cooling. Sci China Chem 2022. [DOI: 10.1007/s11426-022-1259-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
|
21
|
Family of Nanoclusters, Ln 33 (Ln = Sm/Eu) and Gd 32, Exhibiting Magnetocaloric Effects and Fluorescence Sensing for MnO 4. Inorg Chem 2022; 61:8861-8869. [PMID: 35653200 DOI: 10.1021/acs.inorgchem.2c00898] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
A family of nanoclusters, [Ln33(EDTA)12(OAc)2(CO3)4(μ3-OH)36(μ5-OH)4(H2O)38]·OAc·xH2O (x ≈ 50, Ln = Sm for 1; x ≈ 70, Ln = Eu for 2) and [Gd32(EDTA)12(OAc)2(C2O4)(CO3)2(μ3-OH)36(μ5-OH)4(H2O)36]·x(H2O) (x ≈ 70 for 3; H4EDTA = ethylene diamine tetraacetic acid), was prepared through the assembly of repeating subunits under the action of an anion template. The analysis of the structures showed that compounds 1 and 2 containing 33 Ln3+ ions were isostructural, which were constructed by three kinds of subunits in the presence of CO32- as an anion template, while compound 3 had a slightly different structure. Compound 3 containing 32 Gd3+ ions was formed by three types of subunits in the presence of CO32- and C2O42- as a mixed anion template. The CO32- anions came from the slow fixation of CO2 in the air. Meanwhile, one kind of high-nuclearity lanthanide clusters showed high chemical stability. The quantum Monte Carlo (QMC) calculation suggested that weak antiferromagnetic interactions were dominant between Gd3+ ions in 3. Magnetocaloric studies showed that compound 3 had a large entropy change of 43.0 J kg-1 K-1 at 2 K and 7 T. Surprisingly, compound 2 showed excellent recognition and detection effects for permanganate in aqueous solvents based on the fluorescence quenching phenomenon.
Collapse
|
22
|
Novel Cerium-Based Sulfide Nano-Photocatalyst for Highly Efficient CO 2 Reduction. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2022; 18:e2201332. [PMID: 35451152 DOI: 10.1002/smll.202201332] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/01/2022] [Revised: 03/31/2022] [Indexed: 06/14/2023]
Abstract
To address the environmental crisis caused by excessive emissions of CO2 , the development of effective photocatalysts for the conversion of CO2 into chemicals has emerged as one of the most promising strategies. Herein, beyond those well-studied materials, a rare-earth sulfide-based nanocrystal NaCeS2 is fabricated and investigated for efficient and selective conversion of CO2 into CO, where the role of Ce ions is crucial. Firstly, the hybridization of Ce 4f and Ce 5d orbitals contributes to the photoresponsive band structure of NaCeS2 . Secondly, due to the charge rearrangement supplied by the incompletely filled 4f orbitals of Ce ions, NaCeS2 exhibits excellent charge separation efficiency and CO2 adsorption affinity, reducing the energy barrier for the conversion from CO2 to CO. Moreover, a NaCeS2 -MoS2 heterostructure is also designed to further boost the electron transfer from the Mo site to the Ce site, which results in an improvement of the catalytic reduction yield from 7.24 to 23.42 µmol g-1 within 9 h (both better than TiO2 controls). This work offers a platform for the development of rare-earth-based photocatalysts for CO2 conversion.
Collapse
|
23
|
Abstract
Assembling and studying high-nuclearity 3d-4f metal clusters represent a pregnant and challenging research hotspot. Based on anionic template and ligand-controlled hydrolytic methods, two heterometallic metal clusters, formulated as [Gd23Ni20(DTA)20(CO3)4(CH3COO)6(SiO4)4(CH3CH2OH)2(μ3-OH)33(μ2-OH)4(H2O)16]·Cl2·30H2O and [Eu23Ni20(DTA)20(CO3)4(CH3COO)6(SiO4)4(CH3CH2OH)2(μ3-OH)33(μ2-OH)4(H2O)16]·Cl2·46H2O (abbreviated as Gd23Ni20, Eu23Ni20, H2DTA = thiodiglycolic acid), are successfully obtained, which both feature similar double-shell-shaped structures with a Ni20 building unit encapsulating a Ln23 aggregation. The structural analysis illustrates that the SiO44- anion, serving as the anionic template in this work, is reported for the second time in 3d-4f metal clusters. In terms of the magnetic properties, large amounts of Gd3+ and Ni2+ ions contribute to the MCE of compound Gd23Ni20, along with 38.15 J kg-1 K-1 at ΔH = 7.0 T for 2.0 K. It is worth mentioning that compound Gd23Ni20 exhibits an excellent magnetic entropy change at low fields (-ΔSm = 19.10 J kg-1 K-1 at 2.0 K for ΔH = 2.0 T). In addition, Gd23Ni20 exhibits preferable solvent and thermal stability.
Collapse
|
24
|
Hierarchical Assembly of Coordination Macromolecules with Atypical Geometries: Gd 44 Co 28 Crown and Gd 95 Co 60 Cage. Angew Chem Int Ed Engl 2022; 61:e202200537. [PMID: 35148015 DOI: 10.1002/anie.202200537] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2022] [Indexed: 12/15/2022]
Abstract
The discovered giant clusters are always highly symmetric owing to the spontaneous assembly of one or two basic units. Herein we report the Gd44 Co28 crown and Gd95 Co60 cage, formulated as [Gd44 Co28 (IDA)20 (OH)72 (CO3 )12 (OAc)28 (H2 O)64 ]⋅(ClO4 )24 and [Na4 Gd95 Co60 (IDA)40 (OH)150 (CO3 )40 (OAc)58 (H2 O)164 ] ⋅ (ClO4 )41 (H2 IDA=iminodiacetic acid), respectively, by providing a library containing multiple low-nuclearity units. The heart-like units and crown-like tetramer found in both compounds indicate unprecedented assembly levels, leading to an atypical geometry characteristic compared to the giant clusters directly assembled by regular units. These two clusters not only significantly increase the size of Ln-Co clusters but also exhibit the enhanced magnetic entropy change at ultra-low temperatures. This work provided an effective way to fabricate cluster compounds with giant size and geometry complexity simultaneously.
Collapse
|
25
|
Highly sensitive sensing device based on highly luminescent lanthanide nanocluster for biomarker in human urine and serum. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2022; 270:120782. [PMID: 34973612 DOI: 10.1016/j.saa.2021.120782] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/31/2021] [Revised: 12/12/2021] [Accepted: 12/16/2021] [Indexed: 06/14/2023]
Abstract
The level of L-kynurenine (L-kyn) can reflect the health state of human body, and the determination of L-kyn can be used for the medical diagnosis of several cancers and neurological diseases. In this work, a series of air-, water-, and thermo-stable dinuclear lanthanide nanoclusters [Ln2(2,5-DFBA)6(phen)2] (Tb 1, Eu 2, Gd 3, 2,5-DFBA = 2,5-difluorobenzoic acid, phen = 1,10-phenanthroline) are obtained by a facial method. 1 and 2 show very high luminescence quantum yields (QYs) of 71.7% and 81.8%, respectively. Interestingly, investigation reveals that 1 is a quick, highly sensitive and selective sensor for L-kyn in real samples of urine and serum. Furthermore, transmission electron microscope (TEM) results reveal that nanocluster 1 is stable in solution and can be uniform distributed on the base, suggesting it can be deposited on various supports to fabricate sensing devices. Thus, 1 is fabricated into a sensitive test paper for the eye-readable detection of L-kyn in real samples of human urine and serum. The limit of detection (LOD) as low as 0.3 μM, which is enough to rapidly determine L-kyn in human body liquor (usually 5 μM in healthy human body).
Collapse
|
26
|
|
27
|
Two Heterometallic Nanoclusters [Dy III4Ni II8] and [Dy III10Mn III4Mn II2]: Structure, Assembly Mechanism, and Magnetic Properties. Inorg Chem 2022; 61:3655-3663. [PMID: 35167747 DOI: 10.1021/acs.inorgchem.1c03768] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
A full understanding of the assembly mechanisms of coordination complexes is of great importance for a directional synthesis under control. We thus explored here the formation mechanisms of the two new heterometallic nanoclusters [DyIII4NiII8(μ3-OH)8(L)8(OAc)4(H2O)4]·3.25EtOH·4CH3CN (1) and [DyIII10MnIII4MnII2O4(OH)12(OAc)16(L)4(HL)2(EtOH)2]·2EtOH·2CH3CN·2H2O (2) with different cubane-based squarelike ring structures, which were obtained from the reactions of 4-bromo-2-[(2-hydroxypropylimino)methyl]phenol (H2L) with Dy(NO)3·6H2O and the transition metal salt Ni(OAc)2·4H2O or Mn(OAc)2·4H2O. The high-resolution electrospray ionization mass spectrometry (HRESI-MS) tests showed that the skeletons of clusters 1 and 2 have a high stability under the measurement conditions for HRESI-MS. The intermediates formed in the reaction courses of clusters 1 and 2 were tracked using time-dependent HRESI-MS, which helped to determine the proposed hierarchical assembly mechanisms for 1 (H2L → NiL → Ni2L2 → Ni3L4 → Ni4L4 → DyNi4L5 → Dy2Ni6L6 → Dy3Ni6L6 → Dy3Ni7L7 → Dy4Ni8L8) and 2 (H2L → MnL → DyMnL → DyMn2L → Dy2Mn2Lx → Dy8Mn2L2 → Dy10Mn2L2 → Dy10Mn6Lx and H2L → DyL → Dy4L2 → Dy6L2 → Dy8Mn2L2 → Dy10Mn2L2 → Dy10Mn6Lx). This is one of the rare examples of investigating the assembly mechanisms of 3d-4f heterometallic clusters. Magnetic studies indicated that the title complexes both show slow magnetic relaxation behaviors and cluster 1 is a field-induced single-molecule magnet.
Collapse
|
28
|
Hierarchical Assembly of Coordination Macromolecules with Atypical Geometries: Gd44Co28 Crown and Gd95Co60 Cage. Angew Chem Int Ed Engl 2022. [DOI: 10.1002/ange.202200537] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
|
29
|
Design of Molecular Magnetic Materials Based on a New Family of Mixed-Lanthanide Co-Ln Clusters by the Use of the 1,3-Bis[tris(hydroxymethyl)-methylamino]propane Ligand. Polyhedron 2022. [DOI: 10.1016/j.poly.2022.115754] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
|
30
|
Printing Air-Stable High- Tc Molecular Magnet with Tunable Magnetic Interaction. NANO LETTERS 2022; 22:545-553. [PMID: 34981943 DOI: 10.1021/acs.nanolett.1c01879] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
High-Tc molecular magnets have amassed much promise; however, the long-standing obstacle for its practical applications is the inaccessibility of high-temperature molecular magnets showing dynamic and nonvolatile magnetization control. In addition, its functional durability is prone to degradation in oxygen and heat. Here, we introduce a rapid prototyping and stabilizing strategy for high Tc (360 K) molecular magnets with precise spatial control in geometry. The printed molecular magnets are thermally stable up to 400 K and air-stable for over 300 days, a significant improvement in its lifetime and durability. X-ray magnetic circular dichroism and computational modeling reveal the water ligands controlling magnetic exchange interaction of molecular magnets. The molecular magnets also show dynamical and reversible tunability of magnetic exchange interactions, enabling a colossal working temperature window of 86 K (from 258 to 344 K). This study provides a pathway to flexible, lightweight, and durable molecular magnetic devices through additive manufacturing.
Collapse
|
31
|
Abstract
The present work is part of our ongoing quest for developing functional inorganic complexes using unorthodox pyridyl-pyrazolyl-based ligands. Accordingly, we report herein the synthesis, characterization, and luminescence and magnetic properties of four 3d-4f mixed-metal complexes with a general core of Ln2Zn6 (Ln = Dy, Gd, Tb, and Eu). In stark contrast to the popular wisdom of using a compartmental ligand with separate islands of hard and soft coordinating sites for selective coordination, we have vindicated our approach of using a ligand with overcrowded N-coordinating sites that show equal efficiency with both 4f and 3d metals toward multinuclear cage-cluster formation. The encouraging red and green photolumiscent features of noncytotoxic Eu2Zn6 and Tb2Zn6 complexes along with their existence in nanoscale dimension have been exploited with live-cell confocal microscopy imaging of human breast adenocarcinoma (MCF7) cells. The magnetic features of the Dy2Zn6 complex confirm the single-molecule-magnet behavior with befitting frequency- and temperature-dependent out-of-phase signals along with an Ueff value of ∼5 K and a relaxation time of 8.52 × 10-6 s. The Gd2Zn6 complex, on the other hand, shows cryogenic magnetic refrigeration with an entropy change of 11.25 J kg-1 K-1 at a magnetic field of 7 T and at 2 K. Another important aspect of this work reflects the excellent agreement between the experimental results and theoretical calculations. The theoretical studies carried out using the broken-symmetry density functional theory, ORCA suite of programs, and MOLCAS calculations using the complete-active-space self-consistent-field method show an excellent synergism with the experimentally measured magnetic and spectroscopic data.
Collapse
|
32
|
Assembly of pinwheel/twist-shaped chiral lanthanide clusters with rotor structures by an annular/linear growth mechanism and their magnetic properties. Dalton Trans 2022; 51:17040-17049. [DOI: 10.1039/d2dt02653h] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
This is the first time that an annular/linear growth mechanism has been proposed for the directional construction of lanthanide clusters with specific shapes.
Collapse
|
33
|
Magnetocaloric effect and slow magnetic relaxation in peroxide-assisted tetranuclear lanthanide assemblies. Inorg Chem Front 2022. [DOI: 10.1039/d2qi01260j] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Investigation of a series of rare peroxide-assisted tetranuclear lanthanide assemblies revealed both significant magnetocaloric effect and slow magnetic relaxation.
Collapse
|
34
|
Wheel-like Gd42 Polynuclear Complex with Significant Magnetocaloric Effect. CrystEngComm 2022. [DOI: 10.1039/d2ce00315e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Two novel wheel-like lanthanide nanoclusters with 42 nuclearity [Ln42L14(OH)28(OAc)84] (abbreviated as Ln42, 1-Gd; 2-Dy, HL=3-methoxysalicylaldehyde O-vanillin) were structurally and magnetically characterized. The Ln42 species were constructed by O-vanillin and lanthanide...
Collapse
|
35
|
Efficiently increasing low-field magnetic entropy by incorporating SO32− into Gd22Ni21 clusters. Dalton Trans 2022; 51:2669-2673. [DOI: 10.1039/d1dt03314j] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
One distinct nanosized cluster, Gd22Ni21, was isolated by the mixed-anion-templates (SO32- and SO42-), which was firstly reported in 3d-4f metal clusters. Additionally, Gd22Ni21 shows the largest low-field magnetic entropy change...
Collapse
|
36
|
Truncation reaction regulates the out-to-in growth mechanism to decrypt the formation of brucite-like dysprosium clusters. Dalton Trans 2021; 51:197-202. [PMID: 34878449 DOI: 10.1039/d1dt03137f] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Specially shaped high-nuclear lanthanide cluster assembly has attracted widespread attention, but the study of their self-assembly mechanism is still stagnant. Herein, we used a polydentate chelating bis-acylhydrazone ligand to construct a rare 16-nuclear dysprosium cluster 1 with a brucite-like structure. The capture agents, pivalic acid and di(pyridin-2-yl)methanone, were added into the reaction system, and the hexanuclear dysprosium cluster 2 and heptanuclear dysprosium cluster 3 were obtained, respectively. Clusters 2 and 3 support the out-to-in growth mechanism as key evidence. To the best of our knowledge, this study is the first to use truncation reaction to decipher the formation mechanism of high-nuclear lanthanide clusters.
Collapse
|
37
|
Abstract
Lanthanide-oxo/hydroxo clusters (LOCs) in this mini-review refer to polynuclear complexes featuring a polyhedral metal-oxo/hydroxo cluster core of lanthanide ions exclusively or with coexisting 3d metal ions. We summarize herein the recent works using this unique family of cluster complexes for catalysis; this aspect of research stands in stark contrast to their extensively studied synthetic and structural chemistry as well as the much-researched magnetic properties. Following a brief introduction of the synthetic strategies for these clusters, pertinent results from available literature reports are surveyed and discussed according to the types of catalyzed reactions. Particular attention was paid to the selection of a cluster catalyst for a specific type of reactions as well as the corresponding reaction mechanism. To the end, the advantages and challenges in utilizing LOCs as multifunctional catalysts are summarized, and possible future research directions are proposed.
Collapse
|
38
|
Heterometallic Ce IV/ V V Oxo Clusters with Adjustable Catalytic Reactivities. J Am Chem Soc 2021; 143:21056-21065. [PMID: 34873904 DOI: 10.1021/jacs.1c11208] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Heterometallic CeIV/M oxo clusters are underexplored yet and can benefit from synergistic properties from combining cerium and other metal cations to produce efficient redox catalysts. Herein, we designed and synthesized a series of new Ce12V6 oxo clusters with different capping ligands: Ce12V6-SO4, Ce12V6-OTs (OTs: toluenesulfonic acid), and Ce12V6-NBSA (NBSA: nitrobenzenesulfonic acid). Single crystal X-ray diffraction (SCXRD) for all three structures reveals a Ce12V6 cubane core formulated [Ce12(VO)6O24]18+ with cerium on the edges of the cube, vanadyl capping the faces, and sulfate on the corners. While infrared spectroscopy (IR), ultraviolet-visible spectroscopy (UV-vis), electrospray ionization mass spectrometry (ESI-MS), and proton nuclear magnetic resonance (1H NMR) proved the successful coordination of the organic ligands to the Ce12V6 core, liquid phase 51V NMR and small-angle X-ray scattering (SAXS) confirmed the integrity of the clusters in the organic solutions. Furthermore, functionalization of the Ce12V6 core with organic ligands both provides increased solubility in term of homogeneous application and introduces porosity to the assemblies of Ce12V6-OTs and Ce12V6-NBSA in term of heterogeneous application, thus allowing more catalytic sites to be accessible and improving reactivity as compared to the nonporous and less soluble Ce12V6-SO4. Meanwhile, the coordinated ligands also influenced the electronic environment of the catalytic sites, in turn affecting the reactivity of the cluster, which we probed by the selective oxidation of 2-chloroethyl ethyl sulfide (CEES). This work provides a strategy to make full use of the catalytic sites within a class of inorganic sulfate capped clusters via organic ligand introduction.
Collapse
|
39
|
A new family of boat-shaped Ln 8 clusters exhibiting the magnetocaloric effect and slow magnetic relaxation. Dalton Trans 2021; 50:13925-13931. [PMID: 34528636 DOI: 10.1039/d1dt02390j] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Designing and synthesizing lanthanide clusters have always been a research hotspot. Herein, three lanthanide clusters with the formula [Ln8(IN)14(μ3-OH)8(μ2-OH)2(H2O)8]·xH2O (Ln = 1-Gd and x = 11; Ln = 2-Dy and x = 8; Ln = 3-Eu and x = 8) have been isolated in the presence of isonicotinic acid under solvothermal conditions. Structural analysis indicates that those three compounds are isostructural, featuring boat-shaped {Ln8} metal frameworks. Magnetic measurements reveal that 1-Gd exhibits a larger MCE with the maximum -ΔSm value of 31.77 J kg-1 K-1 at 2 K for ΔH = 7 T, while 2-Dy displays slow magnetization relaxation. Besides, the photoluminescence properties of 3-Eu were investigated.
Collapse
|
40
|
Efficient Hole Trapping in Carbon Dot/Oxygen-Modified Carbon Nitride Heterojunction Photocatalysts for Enhanced Methanol Production from CO 2 under Neutral Conditions. Angew Chem Int Ed Engl 2021; 60:20811-20816. [PMID: 34288316 PMCID: PMC8519127 DOI: 10.1002/anie.202105570] [Citation(s) in RCA: 51] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2021] [Revised: 06/28/2021] [Indexed: 12/04/2022]
Abstract
Artificial photosynthesis of alcohols from CO2 is still unsatisfactory owing to the rapid charge relaxation compared to the sluggish photoreactions and the oxidation of alcohol products. Here, we demonstrate that CO2 is reduced to methanol with 100 % selectivity using water as the only electron donor on a carbon nitride-like polymer (FAT) decorated with carbon dots. The quantum efficiency of 5.9 % (λ=420 nm) is 300 % higher than the previously reported carbon nitride junction. Using transient absorption spectroscopy, we observed that holes in FAT could be extracted by the carbon dots with nearly 75 % efficiency before they become unreactive by trapping. Extraction of holes resulted in a greater density of photoelectrons, indicative of reduced recombination of shorter-lived reactive electrons. This work offers a strategy to promote photocatalysis by increasing the amount of reactive photogenerated charges via structure engineering and extraction before energy losses by deep trapping.
Collapse
|
41
|
Efficient Hole Trapping in Carbon Dot/Oxygen‐Modified Carbon Nitride Heterojunction Photocatalysts for Enhanced Methanol Production from CO
2
under Neutral Conditions. Angew Chem Int Ed Engl 2021. [DOI: 10.1002/ange.202105570] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
|
42
|
A two dimensional Gd
III
coordination polymer based on isonicotinic acid N‐oxide with large magnetocaloric effect. Z Anorg Allg Chem 2021. [DOI: 10.1002/zaac.202100033] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
|
43
|
3d-4f Heterometallic cluster incorporated polyoxoniobates with magnetic properties. Chem Commun (Camb) 2021; 57:8624-8627. [PMID: 34369518 DOI: 10.1039/d1cc03262c] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
A series of 3d-4f heterometallic cluster incorporated polyoxoniobates (PONbs) with different magnetic properties were first made and characterized. This work not only provides a promising strategy to make new heterometallic cluster incorporated PONbs but also demonstrates an ideal model to probe how transition-metal ions influence the magnetic property of PONbs.
Collapse
|
44
|
A Purely Inorganic Quasi-Keggin Polyoxometalate for Photocatalytic Conversion of Carbon Dioxide to Carbon Monoxide. Chempluschem 2021; 86:1014-1020. [PMID: 34286917 DOI: 10.1002/cplu.202100260] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2021] [Revised: 07/01/2021] [Indexed: 01/06/2023]
Abstract
A pure inorganic cluster, H47 Na2 Co4 Mo24 (PO4 )11 O72 ⋅ 15H2 O (denoted as {Co4 Mo24 }), has been successfully synthesized by hydrothermal method. Notably, the assembly of a central {Co2 PO4 } tetrahedron and four peripheral {Co[P4 Mo6 ]} fragments gives rise to a rare "quasi-Keggin" structure of {Co4 Mo24 }, in which Co linkers continue to bridge adjacent substructures, resulting in the generation of 3D framework with large cavities. Benefitting from the combination of strong reductive {P4 Mo6 } units and Co active centers, the photocatalytic system with {Co4 Mo24 } as heterogeneous catalyst exhibits excellent activity for CO2 conversion to CO, offering the CO formation rate of 1848.3 μmol g-1 h-1 with high selectivity of 97.0 %. Besides, thermogravimetric and X-ray diffraction analysis confirm that {Co4 Mo24 } can maintain stable during the photocatalytic reaction process.
Collapse
|
45
|
Abstract
A high-nuclearity 3d-4f cluster of [Gd30CoII6CoIII6(OH)56(NO3)12(CH3COO)30(H2O)30]·(NO3)22·(en)3·(H2O)3 (1) was synthesized through the reaction of Gd(NO3)3·6H2O, Co(NO3)2·6H2O, and sodium acetate in a mixture of ethanediamine (en), ethanol, and deionized water. The cluster core in 1 features a double-shell structure with a Co12 icosahedron encapsulating a Gd30 icosidodecahedron. A magnetic study reveals that separating Co2+ ions with Gd3+ ions can effectively reduce the magnetic interaction of 3d-4f clusters. Significantly, the magnetocaloric effect (MCE) of 1 at 2 K and 7 T is up to 44.7 J kg-1 K-1, the largest MCE reported to date in the 3d-4f metal clusters.
Collapse
|
46
|
Erbium Single Atom Composite Photocatalysts for Reduction of CO 2 under Visible Light: CO 2 Molecular Activation and 4f Levels as an Electron Transport Bridge. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2021; 17:e2102089. [PMID: 34047048 DOI: 10.1002/smll.202102089] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/10/2021] [Revised: 04/30/2021] [Indexed: 06/12/2023]
Abstract
It is still challenging to design a stable and efficient catalyst for visible-light CO2 reduction. Here, Er3+ single atom composite photocatalysts are successfully constructed based on both the special role of Er3+ and the special advantages of Zn2 GeO4 /g-C3 N4 heterojunction in the photocatalysis reduction of CO2 . Especially, Zn2 GeO4 :Er3+ /g-C3 N4 obtained by in situ synthesis is not only more conducive to the tight junction of Zn2 GeO4 and g-C3 N4 , but also more favorable for g-C3 N4 to anchor rare-earth atoms. Under visible-light irradiation, Zn2 GeO4 :Er3+ /g-C3 N4 shows more than five times enhancement in the catalytic efficiency compared to that of pure g-C3 N4 without any sacrificial agent in the photocatalytic reaction system. A series of theoretical and experimental results show that the charge density around Er, Ge, Zn, and O increases compared with Zn2 GeO4 :Er3+ , while the charge density around C decreases compared with g-C3 N4 . These results show that an efficient way of electron transfer is provided to promote charge separation, and the dual functions of CO2 molecular activation of Er3+ single atom and 4f levels as electron transport bridge are fully exploited. The pattern of combining single-atom catalysis and heterojunction opens up new methods for enhancing photocatalytic activity.
Collapse
|
47
|
A new family of decanuclear Ln 7Cr 3 clusters exhibiting a magnetocaloric effect. RSC Adv 2021; 11:17346-17351. [PMID: 35479672 PMCID: PMC9033162 DOI: 10.1039/d1ra02734d] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2021] [Accepted: 05/05/2021] [Indexed: 01/16/2023] Open
Abstract
Two dimeric Ln–Cr clusters with formula {Ln(H2O)8[Ln6Cr3(L)6(CH3COO)6(μ3-OH)12(H2O)12]}·(ClO4)6·xH2O (Ln = Gd, x = 35 for 1 and Ln = Dy, x = 45 for 2, HL = 2-pyrazinecarboxylic acid) were obtained by a ligand-controlled hydrolytic method with a mixed ligand system (2-pyrazinecarboxylic acid and acetate). Single crystal structure analysis showed that two trigonal bipyramids of [Gd3Cr2(μ3-OH)6]9+ worked as building blocks in constructing the metal-oxo cluster core of [Gd6Cr3(μ3-OH)12]15+ by sharing a common top – a Cr3+ ion. Additionally, compound 1 forms a three-dimensional framework with a one-dimensional nanopore channel along the a-axis through a hydrogen-bond interaction between the cationic cluster core and the free mononuclear cation [Gd(H2O)8]3+ and the π-bond interactions of the pyrazine groups on the two cationic cluster cores. Magnetic calculations indicated a weak ferromagnetic coupling interaction for Gd⋯Gd and Gd⋯Cr in compound 1, with its magnetic entropy change (−ΔSm) reaching 21.1 J kg−1 K−1 at 5 K, 7 T, while compound 2 displayed an obvious frequency-dependency at Hdc = 2000 Oe. Two decanuclear Ln–Cr clusters Ln7Cr3 were obtained, which formed a three-dimensional framework with one-dimensional nanopore channel through hydrogen-bond and π-bond interactions. Gd7Cr3 had a magnetic entropy change of 21.1 J kg−1 K−1 at 5 K, 7 T.![]()
Collapse
|
48
|
The chain-shaped coordination polymers based on the bowl-like Ln18Ni24(23.5) clusters exhibiting favorable low-field magnetocaloric effect. CHINESE CHEM LETT 2021. [DOI: 10.1016/j.cclet.2021.04.042] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
|
49
|
Recent advances in g-C 3N 4 composites within four types of heterojunctions for photocatalytic CO 2 reduction. NANOSCALE 2021; 13:6692-6712. [PMID: 33885474 DOI: 10.1039/d0nr09177d] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Studies of photocatalytic conversion of CO2 into hydrocarbon fuels, as a promising solution to alleviate global warming and energy issues, are booming in recent years. Researchers have focused their interest in developing g-C3N4 composite photocatalysts with intriguing features of robust light harvesting ability, excellent catalysis, and stable performance. Four types of heterojunctions (type-II, Z-scheme, S-scheme and Schottky) of the g-C3N4 composites are widely adopted. This review aims at presenting and comparing the photocatalytic mechanisms, characteristics, and performances of g-C3N4 composites concerning these four types of heterojunctions. Besides, perspectives and undergoing efforts for further development of g-C3N4 composite photocatalysts are discussed. This review would be helpful for researchers to gain a comprehensive understanding of the progress and future development trends of g-C3N4 composite heterojunctions for photocatalytic CO2 reduction.
Collapse
|
50
|
|