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A series of hollow carbon nanospheres embedded with MRI agents γ-Fe2O3 and GdPO4 nanoparticles (Fe–Gd/HCS), were prepared and applied to in vitro/vivo evaluation with well defined sizes of ∼100 nm, ∼200 nm, ∼300 nm, respectively.

Immunomodulation has made remarkable progress in fighting infectious disease and cancer. Conventionally, immunomodulation largely relies on chemical/biochemical agents, which, unfortunately, suffer from sever off-target adverse effects. Recent insights into nano-bio interactions suggest that nanomaterials can directly participate in immunomodulation. A range of physical and chemical cues at the nano-bio interface have been harnessed to regulate diverse immuno-signaling for disease control and treatment. In this Minireview, we summarize recent studies on the physical and chemical cues enabled by intrinsic nanomaterials to trigger immunological signaling. First, we discuss physical cues mediated by surface topography, hydrophobicity, charge, and heat at the nano-bio interface for immunomodulation. Then, various nanomaterials enabled chemical cues, such as metal species and oxidative species are outlined. Finally, our perspectives on challenges and possible future directions are provided.

Hierarchically ordered porous materials with tailored and inter-connected macro-, meso-, and micro-pores would facilitate the heterogeneous adsorption and catalysis processes for a wide range of applications but remain a challenge for synthetic chemists. Here, a general and efficient strategy for the synthesis of inverse opal metal-organic frameworks (IO MOFs) with a tunable size of macro-, meso-, and micro-pores is reported. The strategy is based on the step-wise template formation, precursor infiltration, solvo-thermal reaction, and chemical etching. As a proof of the general applicability of this strategy, a series of inverse opal zirconium-based MOFs with intrinsic micro- and/or meso-pores, including UiO-66, MOF-808, NU-1200, NU-1000 and PCN-777, and tunable macropores (1 µm, 2 µm, 3 µm, 5 µm, and 10 µm), have been prepared with outstanding yields. These IO MOFs demonstrate significantly enhanced absorption rates and faster initial hydrolysis rates for organophosphorus (OPs) aggregates compared to those of the pristine MOFs. This work paves the way for the further development of hierarchically ordered MOFs for advanced applications.

In situ incorporating versatile magnetic iron nanoparticles into ordered mesoporous carbon (OMC) by means of synthetic methodology for functional integration is a great challenge. Inspired by the phenomenon of uniovular twins in nature, a homometallic [Fe9(μ3-O)4(O3PPh)3(O2CCMe3)13] ({Fe9P3}) cluster was synthesized and used as the ovulum to in situ produce dual-Fe nanoparticle (γ-Fe2O3 and Fe(PO3)3)-functionalized OMC (dual-Fe/OMC). In vitro magnetic resonance imaging (MRI) studies showed a longitudinal relaxation (r1) and transverse relaxation (r2) of 9.74 and 26.59 mM−1 s−1 with a r2/r1 ratio of 2.73 at 0.5 T. The MRI performances were further examined by mouse model with a subcutaneous HeLa tumor. In addition, the low cytotoxicity, considerable loading capacity and delivery of doxorubicin hydrochloride (DOX) were also studied in vitro. These results demonstrate the feasibility of the concept of uniovular twins in the one-pot preparation of dual-Fe/OMC for functional integration.

We report a robust and rigid etb-type metal–organic framework, in which its pore surface is decorated with flexible ethoxyl groups. It shows unprecedentedly selective adsorption of acetone (ETN value of 0.355, kinetic diameter of 4.6 A) over methanol (ETN value of 0.762, kinetic diameter of 3.6 A) for their azeotropic mixture.

Two phenylethynylplatinum(II) terpyridine (PEPtTPY)-derived polymers PtP1 and PtP2 have been prepared from the coupling reactions of two PEPtTPY-incorporated dialdehydes and an oligo(ethylene glycol)-derived diacylhydrazine which form hydrazone bonds quantitatively. Phosphorescence and absorption studies revealed that in binary MeCN and DMSO the PEPtTPY units of both polymers undergo intramolecular Pt⋯Pt interaction and π–π stacking to induce the backbones of the polymers to form pleated conformations. Adding LiClO4 or NaClO4 further stabilizes the two polymeric pleated foldamers by electrostatically binding the oligo(ethylene glycol) chains to induce the chains to fold.

The problem with metal–organic frameworks (MOFs) as CO2-epoxide cycloaddition catalysts is the ambiguous catalytic sites. No system can precisely modify the structures and thus optimize the catalytic performance. Reticular chemistry is recognized as an efficient approach to systematically control the chemical and structural features as well as the properties of porous, crystalline materials. In this work, a Zn-phosphonocarboxylate framework (ZnPC-2) was employed as a prototype structure to investigate the structure–property relationship (SPR). ZnPC-2 is a porous rutile-type framework constructed by 6-connected Zn3(PO3)2(CO2)4 secondary building unit (Zn3-SBU) and tritopic 5-phosphonobenzene-1,3-dicarboxylic acid (H4pbdc). ZnPC-2 showed the ability to catalyze the CO2 cycloaddition reactions and Zn3-SBU was proved as efficient catalytic site. Guided by reticular chemistry, a series of iso-reticular frameworks, including Hpyr@ZnPC-2 (Hpyr = protonated pyrrolidine, Hpyr is fixed by hydrogen bonding interactions to participate the channel into segments); MZnPC-2 (M = Mg, Mn, Fe, Co, Cu; Zn(II) atoms on Zn3-SBU were partially replaced by M) and ZnPC-2-im (im = imidazole, im coordinates to the apical Zn(II) on Zn3-SBU), were designed and successfully synthesized to explore the precise active site. The catalytic performances over these iso-structures together with density functional theory calculations revealed that the dynamical transformation of the apical Zn (II) on Zn3-SBU from tetrahedral geometry to five coordinated model played the pivotal role during the catalytic process.

Metal-organic frameworks (MOFs) featuring a fcu-type net based on 12-connected [Zr6(μ3-O)4(μ3-OH)4] cluster have received considerable interest for the fundamental investigation of structure-property relationships in a wide range of catalytic reactions. In this work, the bipyridine (bpy) chelate group was introduced into the fcu-type framework of UiO-67, giving UiO-67bpy as the catalyst support. Then, FeCl3 was post-synthetically anchored to the bpy group, resulting into the isolation of FeCl3/UiO-67bpy. Catalyzed hydrolysis of 5-hydroxylmethoxyfurfural (HMF) into levulinic acid (LA) was then explored and revealed that it can efficiently and selectively catalytic convert HMF into LA, which is superior to that of FeCl3/UiO-67 where FeCl3 is encapsulated in the cage of UiO-67 and dispersed on the pore surface. The recyclability studies further confirmed the importance of anchored FeCl3 where there is no significant decrease in catalytic activity as compared with that of FeCl3/UiO-67. Taking the detailed textural porosity and catalytic results of isomorphous structures in consideration, our studies revealed that narrowing the pore size with anchored FeCl3 on the skeleton of the fcu-type Zr-MOF rather than encapsulating FeCl3 inside the cage is more favored for the rehydration reaction of HMF to LA.

Formaldehyde and benzene adsorption on UIO-66 in coordination with gaseous H2O2 is an efficient and recyclable method for removing formaldehyde and benzene. In this study, the interaction mechanism of formaldehyde and benzene coordinated with UIO-66 under the existence of H2O2 was studied using density functional theory. The results showed that the decomposition of H2O2 by UIO-66 was promoted to produce highly oxidizing hydroxyl groups. The structure of formaldehyde obviously changed in H2O2/UIO-66 system after equilibrium. The C H bond of HCHO molecule was easy to break at different adsorption sites of UIO-66. Comparatively, benzene with distorted ring structure tended to chemically bound to the carbon site of UIO-66, but the decomposition of benzene was difficult. Density of states analysis showed that the adsorption between C6H6 and UIO-66 was chemisorption. The study is of great significance for providing theoretical guidance to the removal of organic pollutants from exhaust gas by UIO-66.

Domain pattern evolution driven by temperature and electric (E) field in [100]-, [110]- and [111]-poled Mn-doped Pb(In1/2Nb1/2)–Pb(Mg1/3Nb2/3)O3–PbTiO3 (Mn:PIN–PMN–PT) single crystals has been observed in situ under a polarized light microscope. Furthermore, the anisotropic temperature–electric field phase diagrams are established based on microscopic domain observation and macroscopic dielectric and strain behavior. The temperature-induced phase transitions of [100]- and [111]-poled crystals both follow the sequence rhombohedral (R)–tetragonal (T)–cubic (C). However, [110]-poled crystals undergo an R–orthorhombic (O)–T–C process upon heating. The electric field-induced phase transitions originate from the noncollinearity of the direction of the electric field and the polarization vector, such as R–T with E||[100] direction, R–O and T–O with E||[110] direction and T–R with E||[111] direction. Moreover, the ultrahigh piezoelectric activity is closely related to the field-induced phase transitions, particularly the transformations with low threshold field. By the thermodynamic theory analysis, the phase boundaries contribute to the globally flattened free energy profile, resulting in an enhanced piezoelectric response. Our results are beneficial to further understanding the structure/properties relationship in Mn:PIN–PMN–PT single crystals for applications in high-temperature and high-power devices.

Zn-MOF-74 nanorods with uniform diameters of about 200 nm were successfully prepared by a triethylamine (TEA) assistant solvothermal method. The effects of TEA on the sizes and morphologies of nanoscale particles were investigated. Guided by this method, bimetallic ZnxMn1-x-MOF-74s were facilely prepared to endow the nanomaterial with magnetic resonance imaging (MRI) ability. Nanoscale Zn0.7Mn0.3-MOF-74 were successfully produced with homogenous Mn dispersion. Magnetic resonance relaxivity studies using clinical MRI equipment proved that Zn0.7Mn0.3-MOF-74 nanoparticles show a satisfactory r1 relaxivity value of 6.5 mM−1 s−1. The saturated DOX loading capacity of Zn0.7Mn0.3-MOF-74 nanocarriers was evaluated to 113 mg g−1. After chitosan (CS) coating, cytotoxicity experiments showed that DOX@Zn0.7Mn0.3-MOF-74@CS nanocomposites featured adequate biotolerability and no interference with cellular metabolism. These results indicated great potential of the bimetallic ZnMn-MOF-74s as new biomedical materials integrating cellular drug delivery with MR imaging applications.

Magnetic Fe3O4 nanospheres coated with Mg-MOF-74 have been facilely prepared via epitaxial growth. Owing to the intrinsic hydrophilic pore surface and size-exclusive properties of Mg-MOF-74, the Fe3O4@Mg-MOF-74 core-shell nanoparticles show effective and selective enrichment of 441 N-glycosylation sites of 418 glycopeptides from 125 glycoproteins in 1 μL of human serum.

There is great interest in integration of paramagnetic gadolinium compounds and superparamagnetic iron oxide-based nanoparticles into ordered mesoporous carbon spheres (OMCSs) as a combined platform for T1- and T2-weighted magnetic resonance (MR) imaging and drug carrying. In this work, highly dispersed γ-Fe2O3 and GdPO4 nanoparticle co-functionalized mesoporous carbon spheres were successfully prepared using a 3d–4f heterometallic cluster of [Fe6Gd6(μ3-O)2(CO3)(O3PPh)6(O2CtBu)18] as the precursor. The study reveals that multi-scale confinement effects play a role in concurrent generation of Fe and Gd nanoparticles in the carbon matrix. In addition, dual-mode MR imaging and drug carrying properties were evaluated by in vitro experiments, showing satisfactory r1 and r2 relaxivity values of 8.2 and 94.3 mM−1 s−1, respectively, and doxorubicin hydrochloride (DOX) carrying amount of 132 mg g−1, suggesting potential as a combined system for diagnosis and therapy.

A novel cuprous coordination polymer built of [Cu4ICl] cluster and 4-(1,2,4-triazol-4-yl)phenylphosphonate acid (H2ptz) ligand has been hydrothermally synthesized, in which the CuI is in-situ generated by the reduction reaction from CuII precursors. This compound shows a green fluorescent emission with a maximum peak at 510 nm under N2 flow in solid state, which can be turned off by 21 % O2 flow in minutes. Interestingly, it can be turned on again by switching to N2 flow. A possible mechanism has also been proposed.

Two naphthalene (NP) and bipyridinium (BIPY 2+ ) alternately incorporated polymers P1 and P2 have been prepared through the formation of dynamic hydrazone bonds. The polymers formed NP–BIPY 2+ donor–acceptor interaction-induced pleated secondary structure. Upon reducing the BIPY 2+ units to radical cation BIPY + , intramolecular dimerization of the BIPY + units induced the backbones to afford another pleated secondary structure. Adding electron-rich macrocyclic polyether bis-1,5-dinaphtho[38]crown-10 or electron-deficient cyclobis(paraquat- p -phenylene) cyclophane did not break the first foldamer by complexing the BIPY 2+ or NP units of the polymers, whereas the di(radical cationic) ring of the second cyclophane could break the second foldamer by forming threading complexes with the BIPY + units of the polymers.

Three zinc(II) phosphonocarboxylates, [Zn3 (m-bpc)2 (OH)]⋅(CH3 )2 NH2 ⋅H2 O (1), [Zn2 (m-bpc)(m-Hbpc)(4,4'-bpy)]⋅(CH3 )2 NH2 ⋅H2 O (2) and [Zn3 (m-bpc)2 (4,4'-bpy)(CH3 )2 NH]⋅H2 O (3) (m-H3 bpc=3-phosphonobenzoic acid, 4,4'-bpy=4,4'-bipyridine), have been solvothermally synthesised to generate unique topologies, as characterised by single-crystal XRD. Compound 1 possesses a diamond topology, which has rarely been found among phosphonate-based metal-organic frameworks. Compound 2 shows a 2D layered structure with pendant m-Hbpc and 4, 4'-bpy ligands, in which the layers feature as a zeolite-like network. Compound 3 has a 3D sandwich pillared-layer framework with an interesting double-helix structure. Only 1 shows an adsorption capacity for CO2 of 28.5 cm3 g-1 at 273 K. Luminescence studies revealed that both 1 and 2 could be potential sensors to copper(II) ions.

Metal–organic frameworks with tunable functional groups like solid-solution have received considerable interest. In this paper, a crs-type structure built of [Zn3(OH)(dmtrz)3] triazolate-trinuclear and [Zn2(COO)4] paddlewheel units, linked by 3,5-dimethyl-1,2,4-triazolate (dmtrz) and isophthalate (ipa) ligands (named as MAC-4-A), has been used as a prototype framework. Four types of functional groups (B: 5-hydroxyisophthalate, C: 5-aminoisophthalate, D: 5-ethoxyisophthalate, and E: 5-acetamidoisophthalate) have been integrated into the framework, giving isostructures of MAC-4-B to E, respectively. Then, by the solid-solution framework approach, four group samples are prepared, which are MAC-4-AB-x, MAC-4-AC-x, MAC-4-AD-x, and MAC-4-AE-x (x denoted as the ratio of functional ligands in the framework, x = 0.3, 0.5, 0.7), and their CO2 and N2 adsorptions have been studied. Our results revealed that the CO2 capacity is enhanced with the increase of functional groups and then decreases, showing a maximum uptak...

Two metal–organic frameworks containing a geometrically spin-frustrated trinuclear-triangular copper cluster ([Cu3O]) have been successfully isolated, which are {[Cu4.5(μ3-OH)(dmtrz)3(m-bdc)2.5(H2O)2(CH3OH)(DMF)]·DMF·5H2O}n (MAC-8) and {[Cu5(μ3-OH)(dmtrz)3(bdc)3(H2O)4]·3H2O}n (MAC-9) (Hdmtrz = 3,5-dimethyl-1H-1,2,4-triazole, H2m-bdc = 1,3-benzenedicarboxylic acid, H2bdc = 1,4-benzenedicarboxylic acid, DMF = N′,N-dimethylformamide). Magnetic and gas adsorption studies revealed the successful combination of strong antiferromagnetic properties (Jav = −106.6 and −113.7 cm–1 for [Cu3O] in MAC-8 and MAC-9, respectively) and high surface areas (1058 m2/g for MAC-8 and 1242 m2/g for MAC-9) in both of the structures. Further structural studies revealed that the high surface areas could be ascribed to the unique two-dimensional hexagonal pattern of [Cu3(O)] clusters, in which the [Cu3(O)] clusters are connected to each other in an end-end fashion via mononuclear copper ions/paddle-wheel units.

Two dynamic covalent polymers P1 and P2 were prepared by alternately linking electron-rich tetrathiafulvalene (TTF) and electron-deficient bipyridinium (BIPY(2+) ) through hydrazone bonds. In acetonitrile, the polymers were induced by intramolecular donor-acceptor interactions to form pleated foldamers, which unfolded upon oxidation of the TTF units to the radical cation TTF(.+) . Reduction of the BIPY(2+) units to BIPY(.+) led to the formation of another kind of pleated secondary structures, which are stabilized by intramolecular dimerization of the BIPY(.+) units. The diradical dicationic cyclophane cyclobis(paraquat-p-phenylene) (CBPQT(2(.+)) ) could further force the folded structures to unfold by including the BIPY(.+) units of the polymers. Upon oxidation of the BIPY(.+) units of the cyclophane and polymers to BIPY(2+) , the first folded state was regenerated. Switching or conversion between the four conformational states was confirmed by UV/Vis spectroscopic experiments.

Two Zn(II)-based metal–organic frameworks, namely, [Zn3(Hbptc)2(DMF)2]·2DMF(1) and [Zn5(bptc)3(H2O)]((CH3)2NH2)2(2), (H4bptc = 3,3′,5,5′-biphenyltetracarboxylic acid, DMF = N,N′-dimethylformamide), have been synthesized using different amounts of nitric acid under mixed-solvothermal conditions. 1 and 2 display different coordination geometries and donor ligands for the Zn2+ ions. In 1, only three carboxylic acid groups of H4bptc take part in the construction of the three-dimensional (3-D) framework with Zn2+, and one remains uncoordinated that can bind to other metal ions. Postsynthetic exchange of 1 with Ln3+ cations demonstrates that 1 can effectively capture metal cations and sensitize the visible-emitting Ln3+.

A flexible structure of {[Zn2(dmtrz)2(L1)]·6H2O}n (MAC-11) (Hdmtrz = 3,5-dimethyl-1H,1,2,4-triazole, H2L1 = (E)-4,4′-stilbenedicarboxylic acid), which is a self-catenated rob-type net built of two-dimensional [Zn(dmtrz)] layers pillared by L1 ligands, has been solvothermally synthesized. It shows an interesting thermo/water-induced reversible phase transformation accompanied by a photoluminescence response from 418 nm to 453 nm. Based on an iso-framework of {[Zn2(dmtrz)2(L2)]·4H2O}n (MAC-13, H2L2 = (E)-azobenzene-4,4′-dicarboxylic acid), a pcu-type framework of {[Zn2(trz)2(L1)]·4H2O}n (MAC-14, Htrz = 1H, 1,2,4-triazole), and a layered structure of [Zn(dmtrz)(HCOO)], a possible mechanism for the photoluminescence response to the reversible phase transformation for MAC-11 was also proposed.

A 7-connected Zn4O unit has been theoretically predicted based on basic zinc acetate [Zn4O(CH3COO)6], which was then experimentally extended into a three-dimensional structure featuring three kinds of nanocage in a unit cell.

Cyanide group is a robust electron-mediate ligand, widely used in functional coordination polymers. Synthesis of cyanide-containing functional coordination polymersvia solvothermal in situ reaction is a new efficient approach. In this paper, four novel ternary coordination polymers, namely [Ag3(trz)2(CN)]n (1), [Ag3(detrz)2(CN)]n (2), [Ag4(dptrz)2(CN)2]n (3), [Ag3(dptrz)2(CN)]n (4) (Htrz = 1H-1,2,4-triazole, Hdetrz = 3,5-diethyl-1H-1,2,4-triazole, Hdptrz = 3,5-dipropyl-1H-1,2,4-triazole), were solvothermally synthesized and characterized. The cyanide groups are all in situ generated from C–C cleavage reaction of acetonitrile. The cyanide group acts as terminal group in 1, while as linker in 2, 3, 4. Phosphorescent properties of these in situ products are studied and compared with binary silver-triazole coordination polymers. The results show that phosphorescent emissions of 2, 3, and 4 are red-shifted compared to that of 1.

Three isoreticular zinc(II)-phosphonocarboxylate frameworks, namely {[Zn(3)(pbdc)(2)]·2H(3)O}(n) (ZnPC-2), {[Zn(3)(pbdc)(2)]·Hpd·H(3)O·4H(2)O}(n) (Hpd@ZnPC-2) and {[Co(1.5)Zn(1.5)(pbdc)(2)]·2H(3)O}(n) (CoZnPC-2) (H(4)pbdc=5-phosphonobenzene-1,3-dicarboxylic acid, pd=pyrrolidine), were solvothermally synthesized. ZnPC-2 has a 3D structure based on trinuclear Zn(II) clusters (Zn(3)-SBU) showing 3D interconnected channels. Hpd@ZnPC-2 contains an isoreticular framework of ZnPC-2 with small channels blocked by Hpd molecules. In CoZnPC-2, Zn(II) ions in ZnPC-2 are partially substituted by Co(II) ions. The Friedel-Crafts benzylation reactions were carried out over these isoreticular porous materials. The catalytic results reveal that ZnPC-2 is an excellent heterogeneous Lewis acid catalyst with a high selectivity (>90%) towards less bulky para-oriented products. The catalytic reaction has been proved to occur inside the pore of ZnPC-2, and the immobilized Zn(3)-SBUs are the active sites.

Two novel porous metal–organic frameworks {Zn7(btc)4(dmtrz)2(H2O)5}n (1) and {[Zn6(btc)4(dmtrz)3]·3H3O·2H2O}n (2) (H3btc = 1,3,5-benzenetricarboxylic acid, Hdmtrz = 3,5-dimethyl-1H-1,2,4-triazole) have been solvothermally synthesized. Single-crystal structure analysis reveals that both structure 1 and 2 contain special triazole-carboxylate shared paddle-wheel units. The crucial factors to the assembly of such paddle-wheel units are discussed. Gas adsorption studies suggest that 2 is a potential microporous material for adsorptive separation of CO2 over N2.

How to further increase the upconversion luminescence (UCL) efficiency of core-shell upconversion nanoparticles (UCNPs) is highly desirable for their photoelectric and bio-logical applications. Herein, a novel but facile strategy is proposed to substantially enhance the UCL intensity of NaYF4 based core-shell UCNPs by morphological control. The morphologies of core-shell UCNPs can be optimized from rod-like to spherical like by changing the ratio of oleic acid (OA) to 1-octadecene (ODE) during the shell growth process with other reaction conditions constant. The mechanism of shape control is further investigated based on the competitive absorption between OA molecules and lanthanide ions (Y3+, Yb3+, Er3+ or Tm3+) onto the different crystal axes (a, b and c) to guide their shell growth speed. The absolute quantum yields were up to 2.7% and 1.8% for spherical and rod like core-shell UCNPs under excitation of 980 nm laser (power density of 1.6 W cm-2), respectively. Moreover, the UCL intensity and effective lifetime (τ eff ) of Er3+ emission at 541 nm of spherical like core-shell UCNPs increased by 11.7 and 1.82 folds than rod like core-shell UCNPs. Therefore, our designed novel strategy can greatly improve the UCL efficiency of core-shell UCNPs and promote their development in diverse applications.

A novel three-dimensional (3D) [Ag3(dmtrz)2(CN)]n (1) with a three-fold interpenetrated CdSO4-type net is in situ solvothermal synthesized, and influential factors in the in situ reaction are briefly discussed. The luminescent property studies reveal that 1 shows green phosphorescent emission upon excitation while other binary silver(I)-dmtrz compounds discussed in this paper only emit blue phosphorescence.

Three porous metal−organic frameworks have been constructed from the new developed C3-symmetric hexacarboxylic acid 3,3′,3′′,5,5′,5′′-benzene-1,3,5-triyl-hexabenzoic acid (H6BHB) of different NaCl- and Al2O3-type topologies. The activated metal−organic frameworks (MOFs) exhibit permanent porosities as revealed in their gas and vapor adsorption isotherms, highlighting the promise of this new ligand for the construction of porous MOFs for gas storage and separation.

Two novel metal−organic frameworks (MOFs), Cu(3,4′-bpdc)(H2O)·DMF·2H2O (1) and Cu(3,4′-bpdc)(H2O)·2DMF·4.5H2O (2), have been solvothermally synthesized by the reaction of a unsymmetrically substituted carboxylate ligand 3,4′-biphenyldicarboxylic acid (3,4′-bpdc) and Cu(NO3)2·2.5H2O. X-ray crystal structural analyses reveal that both MOFs possess the binuclear paddle-wheel units [Cu2(O2CR)4], which are linked by the biphenyl connectors, to give two different three-dimensional (3-D) frameworks. The structural diversities are due to the different coordinated arrangements of the two distinct carboxylate groups. In 1, the noncentral symmetrical A−A−B−B arrangement leads to an uncommon twisted Cu-paddlewheel unit, which favors a tetrahedral configuration to generate a 3-fold interpenetrating 3-D framework with a diamond topology. In 2, the paddle-wheel unit constructed by the central symmetrical A−B−A−B arrangement of the ligand acts as a square-planar 4-connected node to give a 2-fold interpenetrating 3-D fram...

Six zinc phosphonocarboxylate hybrid materials, namely, Zn2(pbc)2·2Hdma·DMF·H 2 O (1), Zn( 2 (pbc) 2 ·H 2 teta·H 2 O (2), Zn(pbc)·H 3 O (3), Zn 4 (pbc) 3 ·HTEA (4), Zn 3 (pbc) 2 (en) 2 (5), and Zn 3 (pbc) 2 (H 2 O) (6) (H 3 pbc = 4-phosphono-benzoic acid, DMF = N,N-dimethylformamide, dma = dimethylamine, teta = triethylene tetramine, TEA = triethylamine, en = et thylenediamine) have been synthesized using organic amines as structure-directing agents under mixed-solvothermal condition. These new compounds have been characterized by X-ray single-crystal diffraction together with infrared (IR) spectroscopy, thermogravimetric (TG) analysis, and powder X-ray diffraction (XRD). In structures 1 and 2, the double crankshaft chains constructed by the comer-sharing of ZnO 4 and CPO 3 tetrahedra are cross-linked by the organic moieties of the ligands into three-dimensional (3-D) structures with GIS (gismondine) and GIS-related zeolite topologies. In structure 3, the connectivity between ZnO 4 and CPO 3 results in inorganic (4.6.12) sheets, which are pillared by the benzoic acid group -C 6 H 5 -COO- into a 3-D open framework structure with zeolitic SOD (sodalite) topology. Structures 4-6 are pillar-layered structures where the Zn-O-P layers show different configuration due to the directing effect from different organic amines and solvents employed during the synthesis. The results show that the amines and organic solvents acting as structure-directing agents along with control of reaction condition are effective in achieving varieties of zinc phosphonocarboxylate structures.

Three zinc phosphonocarboxylates, Zn2(pbc)2 x Hdma x H3O x 2 H2O (1), Zn(pbc) x Hdma (2), and Zn4.5(pbc)3(OH)(H2O)0.5 x Hdma (3) (H3pbc = 4-phosphonobenzoic acid, dma = dimethylamine) were synthesized by the mixed solvothermal reaction of Zn(Ac)2 x 2 H2O and 4-phosphonobenzoic acid in N,N-dimethylformamide (DMF) and water. The zigzag and ladderlike chains completely constructed by triply fused 4-membered rings (denoted SBU-1) are linked by the organic moieties to form the 3D zeolite-like structure 1 and the layered structure 2, respectively. As for structure 3, a new second building unit (SBU-2) formed by the inset of the [Zn3O12] trimer into the 4-membered ring as well as SBU-1 is observed. The connections between the two types of SBUs lead to a "zinc phosphate" layer, which is linked by the organic groups to generate a 3D pillar-layered structure. Both solution-mediated and solid-state transformations of 1 to 2 and 3 were observed. A possible mechanism for the transformation is proposed. Gas sorption studies show that 1 has accessible pores for methanol and water and exhibits size selectivity for alcohols.

Using structure-directing agents, pore space partitions of a Zn-phosphonocarboxylate framework have been achieved. Selective adsorption of CO(2) over N(2) has been greatly improved from ca. 9 : 1 to 94 : 1.

A novel family of berylloborophosphates, MIBeBPO (MI = K+, Na+ and NH4+) with the zeolite analcime (ANA) framework topology has been hydrothermally synthesized by using monovalent cations as the templates. The structure of KBeBP2O8·1/3H2O (K-BBP-ANA) was solved by single-crystal X-ray diffraction and crystal data for K-BBP-ANA are: M=254.19, cubic, space group: P213, a=12.427(6) A, V=1919.0(17) A3, Z=12, R1=0.0768, Rw=0.1842. The compound is the first BeBPO4 phase with zeolite-ANA structure, which is built of corner-sharing BeO4, BO4, and PO4 tetrahedra. K-BBP-ANA has three-dimensional distorted eight-ring channels along the crystallographic [1 0 0], [0 1 0] and [0 0 1] directions. The framework charges of BBP-ANA are balanced by the monovalent cations in the channel. The X-ray powder diffraction patterns show the family of MIBeBPO (MI=K+, Na+ and NH4+) are isostructural and their framework structures are thermally stable up to 800 °C.

A novel strategy for preparing highly pure NaYF4-based upconversion nanoparticles (UCNPs) was developed using lanthanide oleate compounds [Ln(OA)3] as the precursor, denoted as the Ln-OA preparation method. Compared to the conventional solvothermal method for synthesizing UCNPs using lanthanide chloride compounds (LnCl3) as the precursor (denoted as the Ln-Cl method), the Ln-OA strategy exhibited the merits of high purity, reduced purification process and a uniform size in preparing core and core-shell UCNPs excited by a 980 or 808 nm near infrared (NIR) laser. This work sheds new insight on the preparation of UCNPs and promotes their application in biomedical fields.

A new three-dimensional (3D) zeolite-type zirconogermanate, (C4N2H12)[ZrGe4O10F2] (designated as FDZG-1), with a low framework density of 13.5 T/1000 A3, has been hydrothermally synthesized by using organic piperazine as template and the inorganic salt ZrO(NO3)2·2H2O as the zirconium source at 160 °C in a mixture of pyridine and water as solvent. Single-crystal X-ray analysis reveals that its framework structure is constructed from a spiro-5 second building unit (SBU) or a parallelepiped-like building block and has a similar topology to cavansite (Ca(VO)Si4O10·4H2O). Large elliptic 10-membered ring channels are clearly observed along the crystallographic c axis and blocked by terminal fluorine atoms. Diprotonated piperazinium cations are located in the cavity center of its parallelepiped building block and form strong hydrogen bonds with oxygen atoms and fluorine atoms in the framework. This compound is not stable towards thermal removal of the organic template at above 350 °C.

A simple procedure has been described to directly synthesize hydrothermally stable, disordered mesoporous aluminosilicate materials with strong surface acidity by using a polymer aluminosilicate precursor, and cationic surfactant cetyltrimethylammonium bromide (CTAB) as the structure-directing agent. The comparison of stability, acidity and catalytic activity for the disordered mesoporous materials and Al-MCM-41 has been studied by X-ray diffraction (XRD), transmission electron microscopy (TEM), N2 adsorption/desorption, infrared spectra, NH3-temperature program desorption (NH3-TPD) and 27Al MAS NMR techniques. The results show that the disordered mesoporous materials are very similar to mesoporous material MCM-41 as regards its uniform mesopore sizes at the mean value of 3.0 nm, while the mesoporous channel arrangement is fully disordered similar to that for KIT-1 prepared by the additive of organic salts. Scanning electron microscopic (SEM) images show that the products have regular microscopic arrays and layer sheet-like morphology. The disordered mesoporous materials are hydrothermally more stable than highly ordered MCM-41. Furthermore, they show stronger acid strength and higher cracking activities than Al-containing MCM-41.

Ordered meso- and macroporous silica films can direct the growth of multiwalled carbon nanotubes from perpendicular to parallel to the substrate surface through control of the distribution of catalysts.

We have proposed an easy method for growth of well-aligned patterned CNTs arrays using 3D cubic ordered mesoporous silica films as the catalyst support combined with the soft-lithography technique....

Pores for thought: A new extra large germanate zeolite-type structure has been synthesized by using high-charge multiamine as a template in a pseudo-aqueous system (DMF/H2 O). The novel zeolite-type germanate with low framework density (11.1) has a 24- and 12-membered ring honeycomb array with three-dimensional intersecting channels.

A 3D porous metal-organic framework and method of making are described. In some embodiments, a 3D porous metal-organic framework may be based on a trinodal (3,3,4) net of zyg topology by the self-assembly of the nonlinear hexacarboxylate (BHB) with the paddle-wheel Cu 2 (COO) 4 cluster. Although its porosity and surface area are moderate, the open copper sites and optimal pore spaces enable the pore spaces to be fully utilized for methane storage, resulting in a high methane storage density and high absolute volumetric methane storage at room temperature and 35 bar. By the immobilization of high density open metal sites and the deliberate control of the pore space for their efficient methane storage, this porous MOF functions as an efficient media for methane and natural gas storage.

The layered-solvothermal synthesis of zinc acetate dihydrate with 5-phosphonobenzene-1,3-dicarboxylic acid yields a three-dimensional rutile-type porous metal–organic framework, which is an anionic open-framework containing local proton transfer with hydrated protons and showing excellent size-selective properties.

A three-dimensional (3D) porous structure of [Cu3(μ3-OH)(μ2-O)(dmtrz)2(HCOO)(μ2-H2O)(H2O)3]·H2O (1) has been in situ solvothermally synthesized. In 1, the trinuclear triangular [Cu3(μ3-OH)(μ2-O)(dmtrz)2] cluster connects itself infinitely, resulting in the type-II channel structure, which is different from that of the rigid type-I channel structure reported previously. Reversible dehydration and rehydration induced crystal-to-amorphous-like phase transformation for structure 1 has been observed and confirmed by PXRD patterns and gas adsorption. Furthermore, as a response to the structural transformation, the stimuli-induced modulation of magnetic properties have been observed.

Solvothermal reaction of [1,1′-biphenyl]-3,3′,5,5′-tetracarboxylic acid (H4bptc), 3,5-diamine-1H-1,2,4-triazole (Hdatrz) and zinc acetate affords a three-dimensional structure of [Zn2(bptc)(datrz)](CH3)2NH2·2H2O (MAC-6). It is a (3,6)-connected framework built of paddle-wheel and triazolate-dinuclear metal clusters together with bptc ligands, and shows a novel (42.6)2(44.66.85) topology. Heating crystal samples of MAC-6 leads to the structure transformation to [Zn2(bptc)(datrz)(H2O)0.5](CH3)2NH2·H2O (MAC-6′), in which the paddle-wheel unit deforms to a dinuclear unit. Remarkably, MAC-6′ can reversibly recover to MAC-6 when the samples of MAC-6′ were immersed into DMF. The deformation and reformation of the paddle-wheel unit were studied by single-crystal-to-single-crystal (SCSC) transformation. In addition, their photoluminescent properties were also studied.