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Via induction of achiral aromatic solvents, two 3-D monochiral 3d–4f MOFs (1 and 2) from the ligand HIN without any chiral auxiliary are uncommonly constructed. The results show that the homochiral compounds 1 and 2 are enantiopure rather than exhibiting enantiomeric excess. Obviously, this work has brought major synthetic advancement in homochiral framework materials of great significance.

Six temperature-dependent Zn(II) complexes 1–6 based on the simple Schiff base L1 from condensation of equivalent 2-pyridine formaldehyde (2-Pfd) and 2-pyridylethylamine (2-Pea) were systematically studied for the first time. These six complexes are: two complexes of ZnL2X2 (1 and 2) involving in situ formed N-rich heterocyclic ligand L2 at 80 °C; two complexes of [Zn2(cis-L3)X4·S] (S = H2O for 3, S = 0 for 5) involving in situ formed azaheterocyclic ligand cis-L3 at 100 °C; and the rest two ones of [[Zn2(trans-L3)X4] (4 and 6) involving in situ formed azaheterocyclic ligand trans-L3 at 120 °C (where X = Cl (1, 3, 4) and N3 (2, 5, 6), L1 = N-(2-pyridylmethyl)-pyridine-2-carbaldimine, L2 = 1-pyridineimidazo-[1,5-a]pyridine, L3 = 1-(1,2-di(pyridin-2-yl)-2-(3-(pyridin-2-yl)H-imidazo-[1,5-a]-pyridin-1-yl)-ethyl)-3-(pyridin-2-yl)H-imidazo-[1,5-a]pyridine). Interestingly, three Cl-based complexes 1, 3, 4 under appropriate conditions can be irreversibly translated into the corresponding N3-based 2, 5, 6, respectively. The possible formation/conversion mechanism shows that the α-H activation in –CHN–CH2– moiety of L1 coordinated to Zn2+ ion should be the original driving force for the intermolecular C–C/C–N coupling and ring formation reactions, meanwhile reaction temperature also plays a very important role during the formation/conversion of 1–6. Moreover, the results indicate that complexes 1–6 have good fluorescence properties as potential fluorescent materials.

A new Cd-based metal–organic framework (Cd-MOF), namely [Cd3(TCPB)2(H2O)2(DMF)2]·7H2O, has been constructed from Cd(NO3)2 and 1,3,5-tri(4-carboxyphenoxy)benzene (H3TCPB) under solvothermal conditions. Single crystal X-ray diffraction analyses reveal that Cd-MOF displays a two-dimensional (3,6)-connected kgd net topology based on linear trinuclear Cd3(COO)6 secondary building units (SBUs) and exhibits one-dimensional opening channels. When treated as a precursor by calcining this Cd-MOF at 800 °C for 2 h, a porous carbon material was prepared. As an anode material for lithium-ion batteries (LIBs), the resulting porous carbon material exhibited an initial discharge of 2486 mA h g−1 and a charge of 1683 mA h g−1 at a current density of 300 mA g−1 with a high initial coulomb efficiency of 98%. After 300 cycles, a high reversible capacity as high as 1285 mA h g−1 could be still maintained, along with good rate capability and superior cyclic stability. The good electrochemical performance can be attributed to the unique pore structure and large surface area, which can largely offer more active sites for Li storage and cause an increase in the ability for the accumulation of charges.

The micro/nanomotors are nanometer or micrometer-sized devices which can be activated by chemical reactions or external physical energy sources. The activated micro/nanomotors display rotation, rolling, shuttling, delivery, contraction, or collective behavior. Compared with the traditional nanotechnology for drug delivery or cargo transport with passive way (micro/nano particles have been moved by micro-fluid in body), biologically or chemically functionalized micro/nanomotors exhibit more attractive potential in chemistry, environment and biomedicine due to their controllable behavior. Over the past decade, great progress has been achieved in the field of micro/nanomotors, especially in fabrication and application of micro/nanomotors. Various shape and functional micro/nanomotors have been created, such as nanowires, microtubes, Janus spheres and helical springs. The operating mechanisms of such motors mainly are self-eletrophoresis, bubble-driven, light-driven, ultrasound-driven, magnetic field-driven or electrical field-driven. They are strongly related to the kind of energy sources, which can be chemical fuels (H2, HCl, I2, H2O, N2H4 and glucose) or a physical stimuli (light, ultrasound, magnetic and electrical). In addition, the applications of micro/nano motors range from environment to biology, such as drug delivery, DNA identification, ions sensing, degradation of biological and chemical warfare agents, oil remove and so on. As a result, micro/nanomotors have become an attractive and significant research field in nanoscience and nanotechnology. Light is the treasure from the nature, to power micro/nanomotors using renewable and environment-friendly light (especially sunlight) is an excited challenge. Besides, a series of unique operations can be easily realized using light to power micro/nanomotors, such as remote control, tunable speed and cyclic on/off motion, which make the light-driven micro/nanomotors to be one of the most attractive nanomachines. With the efforts of scientists over the years, light driven micro/nanomotors have been designed as tubes, Janus spheres, gears and irregular shapes and activated by different mechanisms, such as photocatalytic reactions, photothermal effects, photo-isomerization or photo induced deformation and so on. In fact, these devices are principally characterized according to the type of photo responsive materials. However, no matter what the materials are or how the structures of motors are, the most important and essential mechanism for the propulsion is the gradient field around motors which can be concentration, electrical, thermal or light gradient. Asymmetric motor structure or light field is the key to form such a gradient which could propel motors. Due to the excellent performances of light driven micro/nanomotors, they have been successfully applied in water cleaning, sensing and target therapy. Although the scientists in this research field achieve much valuable success, there still remain many challenges. Challenges result from expending the kinds of fuels, using sunlight to power motors, controlling the direction of motors with new methods, and exploring biocompatible light driven motors et al. In this review, we briefly introduce the micro/nanomotors, and then mainly present a review of the state-of-the-art in light driven micro/nanomotors including the basic design principles, types, operational mechanisms, motion characters and the environmental and biological applications of light driven micro/nanomotors. Finally, we summarize the challenges and outlooks in light driven micro/nanomotors.

Two interesting 1D heterometal chain-like compounds from pyridine-2,6-dicarboxylic acid (H2PDA) and AgNO3 as well as ZnCl2/SmCl3, namely [ZnAg(PDA)2(μ2-H2O)·(H3O)+⋅(H2O)0.25]n (1) and [SmAg(PDA)2(H2O)3·3H2O]n (2), have been solvothermally synthesized by fine control synthetic conditions, and structurally characterized. The results reveal that 1D rac-helical chain 1 containing two independent single-stranded single-helical P-helical and M-helical chains crystallized in the tetragonal I4(1)/a space groups, in which the octahedral Zn2 + center in 1 coordinated to two pyridyl nitrogen atoms and four carboxyl oxygen atoms from two chelating PDA2 − ligands, while the distorted tetrahedral Ag+ center in 1 ligated to two aqueous oxygen atoms and two carboxyl oxygen atoms from two bridging PDA2 − ligands. Under the same reaction conditions except the reactant of SmCl3 replacing ZnCl2, 1-D meso-helical chain 2 with monoclinic P2(1)/n space group, consisting of two adjacent three-stranded single-helical P and M chains connected through Ag O bonds, was obtained. Each Sm3 + ion in 2 was chelated to two PDA2 − anions as tridentate (ONO) ligands and three water molecules that completed the nine-coordinated environment around Sm3 +. The coordination sphere of Ag+ was finished by five carboxyl O atoms from three PDA2 − ligands with highly distorted trigonal bipyramidal geometry. Obviously, different helicity between 1 and 2 closely related to the radius and coordi numbers of the 3d/4f metal cation ions. Moreover, the fluorescent propeties of compounds 1 and 2 were also studied.

A new luminescent terbium-based metal-organic framework [Tb2(PDC)2(SO4)(H2O)6]·2H2O (1) (H2PDC = pyridine-3,5-dicarboxylic acid), has been successfully synthesized under solvothermal condition. Single crystal X-ray diffraction analysis reveals that compound 1 crystallizes in the monoclinic C2/c space group and exhibits a 3D porous (3,4)-connected (33·45·56·6) topological framework based on two-dimensional (2D) [Ln(PDC)]+ layers and SO42 − pillars. Moreover, the luminescent property shows that compound 1 displays intense green luminescence of the typical Tb3 + ion emission. The quenching effects for aromatic organic solvents make it potential application as fluorescent sensor for nitroaromatic explosives.

Two series of lanthanide coordination polymers, {[Ln2(tabc)4(C2O4)(H2O)5]·H2O}n (Ln = Nd (1), Sm (2), Eu (3), Htabc = 4-(1–1,2,4-triazolyl)benzoic acid) and {[Sm(tabc)(1,2-pdc)(H2O)2]·2H2O}n (4), have been constructed via hydrothermal conditions through adding different auxiliary ligands. Compounds 1–3 are two dimensional coordination layer comprised of {Ln1(COO)2} chains and {Ln2(COO)2} dinuclear units which are connected by oxalate groups, whereas compound 4 is one dimensional chain containing {Sm2(COO)2} dinuclear units. The IR spectra and thermal stabilities of all compounds have been studied in detail. Compound 3 shows characteristic emission of Eu3 + ions, and it is noteworthy that the luminescent properties for 2 shows no emission peaks whereas that for 4 exhibits characteristic absorption bands of Sm3 + ions. CCDC: 1478487, 1478488, and 1478495

We present a porous metal-organic framework (MOF) with remarkable thermal stability that exhibits a discharge capacity of 300 mAh g(-1) as an anode material for a lithium-ion battery. Pyrolysis of the obtained MOF gives an anode material with improved capacity (741 mAh g(-1)) and superior cyclic stability.

A multifunctional polyhedral metal–organic framework with a pcu network topology based on supramolecular building blocks can be constructed by the reaction of Eu(NO3)3 and pyridine-3,5-dicarboxylic acid (H2PDC). The basic EuIII paddlewheel nodes as secondary building units (SBUs) are connected by PDC ligands to generate nanosized metal–organic cuboctahedra (MOCs), which are further connected by sharing the paddlewheel SBUs to give rise to a three-dimensional primitive cubic network arrangement. The obtained metal–organic frameworks (MOFs) exhibit excellent catalytic activity toward the cyanosilylation of aromatic aldehydes and could be reused without loss of activity. In addition, they can also be considered as a fluorescent probe for nitrobenzene sensing based on luminescence quenching effects arising from host–guest interactions. This porous MOF combining catalytic and fluorescent properties could further meet the requirement as a multifunctional material.

The notorious shuttle effect and slow reaction kinetics of lithium polysulfides (LiPSs) severely limit the cycle stability and rate performance of lithium sulfur (Li-S) batteries. Herein, we demonstrated that the issue of shuttling effect of LiPSs could be effectively addressed by using a separator coating based on Ni3ZnC0.7 bimetal carbide nanoparticles dispersed in nitrogen-doped porous carbon material matrix containing small amount of Ni metal particles, namely Ni3ZnC0.7/Ni/NCNTs. When used as a separator coating of Li-S cells, the Ni3ZnC0.7 bimetal carbides demonstrated efficient adsorption and catalytic effect towards LiPSs, inhibiting the shuttle effect and enhancing the electrochemical performance of device. The Li-S cell still maintained excellent charging and discharging platform even at a high rate of 7C. Theoretical calculation shows that, compared to the monometal carbide Ni3C, the bimetal carbide Ni3ZnC0.7 possesses the advantageous properties of both sulfophilic sites of Ni and lithophilic sites of Zn, resulting in reduced energy barriers for lithium ion diffusion and improved catalytic capability, thus enhancing reaction kinetics of LiPSs. This work paves a new way to resolving the critical issues of shuttle effect, cycle stability and rate capability of Li-S batteries by taking advantage of synergistic effect of Ni and Zn in the bimetal carbide.

The electron-deficient ester group substitution in the sidechain of the commonly used electron-withdrawing quinoxaline (Qx) unit is seldom studied, while ester-substituted Qx units possess easy syntheses and facile modulation of the polymer solubility, and the enhanced electron-withdrawing property of ester substituted Qx unit can theoretically broaden the optical absorption of the resulting polymers and improve the open circuit voltage in the corresponding organic solar cells (OSCs). In this work, a novel ester-substituted Qx-based narrow bandgap polymer (NBG) donor material PBDTT-EFQx, which exhibits an absorption edge of 790 nm (bandgap < 1.6 eV), is designed and synthesized. Results show that the OSCs composed of PBDTT-EFQx and PC71 BM present the highest power conversion efficiency (PCE) of 6.8%, compared to PCEs of 5.0% for PBDTT-EFQx:ITIC based devices and 4.1% for PBDTT-EFQx:N2200 based devices, respectively. Characterizations and analyses indicate that the PC71 BM-based OSCs have well-matched energy levels, better complementary light absorption, the highest and most balanced carrier mobilities, as well as the lowest degree of recombination losses, and therefore, leading to the highest PCE among the three types of OSCs. This work reveals that the ester-substituted quinoxaline unit is one of the potential building blocks for NBG polymer donors.

Tailoring the alkyl chains of polymeric photovoltaic materials is a cost-effective strategy towards efficient polymer solar cells (PSCs). However, the alkyl chain positioning effect of polymers on the photovoltaic performance remains a crucial issue to be examined. In this contribution, three thieno [3,4-c]pyrrole-4,6-dione (TPD)-based donor polymers 2HD/C8, C8/2BO/C6, and 2BO/C6/C6, in which alkyl side chains are appended at different positions, are developed and examined. Studies show that polymer 2HD/C8 largely outperforms its other two analogues C8/2BO/C6 and 2BO/C6/C6. Results make clear that (i) dispersing alkyl side-chain from the N-site of thieno [3,4-c]pyrrole-4,6-dione (TPD) motifs to the 4,8-di(thiophen-2-yl)benzo [1,2-b:4,5-b']dithiophene (BDTT) or to the backbone thiophene units leads to less crystallinity and decreased face-on packing ratio in correlated BHJ films; (ii) the hole (μh) and electron mobility (μe) show gradual reduction from 2HD/C8- to 2BO/C6/C6-, and further to 2BO/C8/C6-based BHJ devices, which result in serious charge recombination, decreased FF and JSC in the corresponding BHJ devices; (iii) the alkyl chain positioning also impacts the energy levels due to the hyperconjugation effect of alkyl chains, consequently, distinct VOC and energy loss are observed. This examination sheds light on that meticulous tailoring the alkyl chain positions should be considered when developing high-performing polymeric photovoltaic materials.

A novel inverse spinel SnFe2O4, with a polyhedral morphology and a mixed core-shell SnFe2O4@Carbon or Carbon@SnFe2O4 composite are prepared by a facile solvothermal method, and evaluated as anode material for lithium ion batteries (LIBs). The SnFe2O4 exhibits a higher initial discharge/charge capacities of 1212/858 mAh g-1 with an initial coulombic efficiency (ICE) of 70.8% and maintains 812/799 mAh g-1 at the 200th cycle at 0.5 A g-1 and 540/535 mAh g-1 at the 400th cycle even at 4.0 A g-1. An interesting phenomenon that the capacity of pure SnFe2O4 at each current density decreases rapidly first and then increases gradually and remains stable, which is attributed to the polyhedral morphology and the inverse spinel structure. It can be relieved by compositing with carbon forming core-shell SnFe2O4@Carbon or Carbon@SnFe2O4. The composite shows an initial discharge/charge capacities of 1238/820 mAh g-1 with an ICE of 66.2% and maintains much larger capacities of 1223/1200 mAh g-1 at the 200th cycle at 0.5 A g-1 and 608/603 mAh g-1 at the 400th cycle at 4.0 A g-1. The lithium ions storage mechanism is first elucidated as a diffusion control of pure SnFe2O4 and a combination of capacitive and diffusion control of SnFe2O4@C composite, respectively.

Metal–organic frameworks (MOFs) are the newly crystalline porous materials with outstanding structural, compositional, and morphological features, which have garnered much attention in all dimensions of major scientific and engineering fields, including energy storage and conversion. Various pristine MOFs and their derivatives have been developed and used as anode materials in lithium–ion batteries (LIBs). In this review, we specifically focused on MOFs–derived nanostructured metal oxides with diverse structural and compositional features that exhibit exceptional lithium storage capacity. These intriguing nanostructures inherit the multidimensional structure of MOF and the advantage of even distribution of metallic species after thermal decomposition, which facilitates fast reaction kinetics of lithium transportation and ultimately improves the battery performance. Herein, we review and categorise the synthetic strategies to achieve various transitional metal oxide nanostructures/composites obtained from BDC/BTC–based MOFs (H2BDC = 1,4–benzenedicarboxylic acid, H3BTC = 1,3,5–benzenetricarboxylic acid), zeolitic imidazolate frameworks (ZIFs), Prussian blue and Prussian blue analogues (PB and PBAs), and other unusual porous crystalline MOF materials. In addition, we will also compare the electrochemical performances of various metal oxides (MOs) nanostructures obtained via heteroatom doping in the pristine MOF precursor or by tuning their structure. Finally, our discussion will focus on the advantages and future developments in design and fabrication of new MOF–derived metal oxide electrode materials with high energy efficiencies in relation with the next generation rechargeable battery applications.

Metal-organic framework (MOF)-derived hybrids are promising electrode materials in electrochemical energy storage, owing to their high surface area that offers enormous redox sites and excellent conductivity. In this work, MOF-derived cerium oxide/carbon integrated with molybdenum disulfide (CeO2/C/MoS2) hybrid is developed as an electrode material for supercapacitor. Remarkably, integration of CeO2/C with small amount of MoS2 has considerably enhanced the electrochemical performance. Moreover, CeO2/C/MoS2 hybrid exhibited both surface and diffusion-controlled mechanism towards charge storage. The CeO2/C/MoS2 hybrid showed an outstanding specific capacitance (specific capacity) of 1325.67 F g−1 (397.70 C g−1) and excellent cyclic stability with capacitance retention of 92.8% after 1000 charging-discharging cycles, which is significantly higher than that of CeO2/C (727.49 F g−1) or else that of MoS2 (300.33 F g−1) at 1 A g−1. In addition, asymmetric supercapacitor (ASC) fabricated with CeO2/C/MoS2 hybrid and activated carbon (AC) showed remarkable electrochemical performance with high specific capacitance (110.55 F g−1), excellent cyclic stability (even after 1000 cycles) and high energy density of 34.55 Wh kg−1 at a power density of 666.7 W kg−1. Thus, MOF derived CeO2/C integrated MoS2 hybrid is a potential electrode material for the ASCs.

Nano core-shell silicon/carbon (Si/C) composites can efficiently enhance the conductivity and accommodate the volume change for Si. However, new challenges of big specific surface area and high interparticle resistance still weaken its advantages. In order to solve the above problems, we prepared a micron bread-like Si-based composite with high Si content in it, in which buffer space in clustered core-shell units are used to relieve the stress caused by volume expansion, and the N-doped carbon skeleton derived from ZIF-8 is applied to enhance the electrical contact between adjacent core-shell units. Due to the stable bread-like structure, the integrity of stable solid electrolyte interphase layer is maintained, and the lower external surface area retains the coulombic efficiency as high as 95.5% during cycling. The specific capacities of the obtained composite are 1155 mAh g−1 at 2 A g−1 and 815 mAh g−1 at 5 A g−1 in rate performance. After long-term cycling of 500 cycles, the composite still maintains specific capacities of 1109 mAh g−1 at 3 A g−1 and 804 mAh g−1 at 5 A g−1 with ICE of 65.55% in the first three activated cycles.

Lithium sulfur (Li-S) battery is regarded as one of the most promising next generation high-energy storage systems. However, the shuttle effect and sluggish redox kinetics of lithium polysulfides always compromise the cycling performance of Li-S batteries. Herein, an effective strategy is presented to fabricate high-performance Li–S batteries using a 3D network-like nanocomposite of Co/NCNS/CNT, which is obtained via the well-distributed composition of the carbon nanotubes (CNTs) (in situ formed and added) with nitrogen-doped carbon nanosheets (NCNS) as well as Co nanoparticles from carbonization of the nitrogen-rich bio-MOF-100 nanosheets at an inert atmosphere. Owing to good sulphiphilicity, excellent conductivity and high catalytic activity from Co-Nx and Co nanoparticles, Co/NCNS/CNT nanocomposite could effectively adsorb and catalyze the fast conversion of lithium polysulfides. When serving as the separator coating for Li-S cells, the cell shows excellent performances with an initial capacity of 972.4 mAh/g at 2C under a sulfur loading of 2.0 mg/cm2, and excellent cycling stability with the capacity decay of 0.05% per cycle during the 1000 long-term cycles. Furthermore, even at a high sulfur loading of 5 mg/cm2, the specific capacity of 522.1 mAh/g (2.61 mAh/cm2) can be maintained after 500 cycles at 1 C, thus providing a promising path toward advanced Li–S batteries.

Synthetic micro/nanomotors (MNMs) are a particular class of micrometer or nanometer scale devices with controllable motion behavior in solutions by transferring various energies (chemical, optical, acoustic, magnetic, electric, etc.) into mechanical energy. These tiny devices can be functionalized either chemically or physically to accomplish complex tasks in a microcosm. Up to now, MNMs have exhibited great potential in various fields, ranging from environmental remediation, nanofabrication, to biomedical applications. Recently, light-driven MNMs as classic artificial MNMs have attracted much attention. Under wireless remote control, they can perform reversible and repeatable motion behavior with immediate photoresponse. Photocatalytic micro/nanomotors (PMNMs) based on photocatalysts, one of the most important light-driven MNMs, can utilize energy from both the external light source and surrounding chemicals to achieve efficient propulsion. Unlike other kinds of MNMs, the PMNMs have a unique characteristic: photocatalytic property. On one hand, since photocatalysts can convert both optical and chemical energy inputs into mechanical propulsion of PMNMs via photocatalytic reactions, the propulsion generated can be modulated in many ways, such as through chemical concentration or light intensity. In addition, these PMNMs can be operated at low levels of optical and chemical energy input which is highly desired for more practical scenarios. Furthermore, PMNMs can be operated with custom features, including go/stop motion control through regulating an on/off switch, speed modulation through varying light intensities, direction control through adjusting light source position, and so forth. On the other hand, as superoxide radicals can be generated by photocatalytic reactions of activated photocatalysts, the PMNMs show great potential in environment remediation, especially in organic pollutant degradation. In order to construct more practical PMNMs for future applications and further extend their application fields, the ideal PMNMs should be operated in a fully environmentally friendly system with strong propulsion. In the past decade, great progress in the construction, motion regulation, and application of PMNMs has been achieved, but there are still some challenges to realize the perfect system. In this Account, we will summarize our recent efforts and those of other groups in the development toward attractive PMNM systems. First, we will illustrate basic principles about the photocatalytic reactions of photocatalysts and demonstrate how the photocatalytic reactions affect the propulsion of PMNMs. Then, we will illustrate the construction strategies for highly efficient and biocompatible PMNMs from two key aspects: (1) Improvement of energy conversion efficiency to achieve strong propulsion of PMNMs. (2) Expansion of the usable wavelengths of light to operate PMNMs in environment-friendly conditions. Next, potential applications of PMNMs have been described. In particular, environment remediation has taken major attention for the applications of PMNMs due to their photocatalytic properties. Finally, in order to promote the development of PMNMs which can be operated in fully green environments for more practical applications, an outlook of key challenges and opportunities in construction of ideal PMNMs is presented.

Four new metal–organic frameworks (MOFs), [Co3(TCPB)2(CH3OH)4]·4DMF (1), [Cd3(TCPB)2(H2O)4]·3DMF·19H2O (2), [Mn3(TCPB)2(H2O)2(DMF)2]·2DMF (3), and [Zn2(μ3-OH) (TCPB)(H2O)(DEF)]·3DEF (4) (H3TCPB = 1,3,5-tri(4-carboxyphenoxy)benzene), have been successfully synthesized and structurally characterized. Structural analyses show that complexes 1–3 present two-dimensional (3,6)-connected kgd net topology with the Schlafli symbol of (43)2(46·66·83) based on linear trinuclear M3(COO)6 (M = Co, Cd, and Mn) secondary building units (SBUs) and display distinct one-dimensional (1-D) channels. Complex 4 (Zn-TCPB) exhibits a rare three-dimensional twofold interpenetrated (3,6)-connected rutile topology with the Schlafli symbol of (42·610·83) (4·62)2 based on the tetranuclear Zn4(μ3-OH)2(COO)6 clusters, which shows three different types of 1-D opening channels. In addition, as an anode material, the complex 4 (Zn-TCPB) electrode exhibits an irreversible high capacity in the first discharge process and a reversible lithium storage capacity of up to about 455 mA h g−1 at 0.1 A g−1 after 100 cycles. This might provide a new method for finding a promising candidate for the electrode materials in lithium-ion batteries.

Several new coordination polymers (CPs), [Mn(4,3-opybz)2(H2O)2]n (1), [Zn(4,3-opybz)(OH)]n (2), {[Pb(4,3-opybz)(H2O)]·(NO3)}n (3), {[Mn3(4,4-opybz)4(HCOO)2(H2O)4]·6H2O}n (4), Zn(4,4-opybz)2(H2O)2 (5) and {[Pb(4,4-opybz)(4,3-opybz)]·3DMF·7H2O}n (6) (4,4-Hopybz = 4-(4-pyridyl)benzoic acid N-oxide, 4,3-Hopybz = 4-(3-pyridyl)benzoic acid N-oxide), have been successfully synthesized and characterized by elemental analyses, IR spectroscopy, thermogravimetric analysis and single crystal X-ray diffraction. Structural analysis shows that complex 1 features a two-dimensional (2D) layer with a 63 topology. Complexes 2 and 3 present a 2D layer architecture with a 4·82 topology. Complex 4 presents an unusual one-dimensional (1D) chain constructed with linear trinuclear secondary building units (SBUs). Complex 5 has a zero-dimensional (0D) structure which is further connected to form a 2D supramolecular network through O–H⋯O hydrogen bonding. Complex 6 exhibits a 2D layer which is further connected by π⋯π interactions to produce a three-dimensional (3D) supramolecular framework with 1D opening channels. Moreover, as an anode material, complex 6 exhibits a relatively high irreversible capacity of about 860 mA h g−1 in the first discharge process and a reversible lithium storage capacity of up to 405 mA h g−1 at 100 mA g−1 after 100 cycles. The observation of good storage performance demonstrates that CPs are a prospective class of electrode materials for lithium ion batteries (LIBs).

Two samarium(III) complexes showing different luminescent intensity, namely Sm(HL1)2·NO3·2H2O (1) and [SmL2(C2H5OH)2·NO3]2 (2), were constructed via the solvothermal in situ lanthanide metal–ligand reactions of 2-ethoxy-6-((pyridin-2-ylmethylimino)-methyl)phenol (HL) from pyridin-2-ylmethanamine and 3-ethoxy-2-hydroxybenzaldehyde with Sm3+ ion at different temperatures, in which H2L1 resulted from C–C coupling dimerization of HL, while H2L2 from C–C coupling of HL and pyridin-2-ylmethanamine.

Three series of lanthanide coordination polymers with formula [Ln2(PDC)3(H2O)2(DMF)]·4H2O (type I) (Ln = La 1, Pr 2, Sm 3), [(CH3)2NH2][Ln2(PDC)3(HCOO)(H2O)3]·2H2O (type II) (Ln = Tb 4, Ho 5) and [Ln(HPDC)3(H2O)2]·H2O (type III) (Ln = Er 6, Lu 7) (H2PDC = pyridine-3,5-dicarboxylic acid), have been successfully synthesized by the solvothermal reaction of pyridine-3,5-dicarboxylic acid (H2PDC) with the corresponding lanthanide nitrate. Compounds 1–3 are isomorphous and all crystallize in triclinic space group P, showing a 3D microporous framework of pcu topology with square channels along the b-axis. Isostructural compounds 4 and 5 show the same 2D layer network of (4,4)-grid in the monoclinic P21/c space group. Isomorphic 6 and 7 crystallize in the monoclinic Cc space group and present 1D zigzag chains which expand to a 3D supramolecular structure through π⋯π stacking interactions. The structural diversity of these three classes of compounds may be attributed to the effect of lanthanide contraction. They were characterized by infrared spectra (IR), elemental analysis (EA), thermogravimetric analysis (TGA), powder X-ray diffraction (PXRD), and X-ray single crystal diffraction. Furthermore, the catalytic properties of these compounds were investigated and experiments revealed that compounds 1–3 show size-selective catalytic performance for cyanosilylation reactions and could be reused without losing their catalytic activity.

A new class of fluorescein/rhodamine hybrids with two spirolactone rings was reported to exhibit dual-output fluorescent behaviors independently. Isolation and characterization for two diastereomers, trans-RhOH and cis-RhOH, have been made and their X-ray crystal structures determined. In a basic environment, the spirolactone ring on the hydroxyl side will be opened to give a fluorescein-like optical output with the lowest absorptions at 485 and 530 nm emission. On the other hand, a rhodamine-like optical output, i.e., 528 nm absorption and 575 nm emission, will be switched on by a H(+) or a Hg(2+) ion, attributed to the spirolactone ring opening on the amino side. In a methanol-buffer system with different pH values, the corresponding pKa values for the hydroxyl and amino groups were determined as 5.7 and 2.3, respectively. Selective Hg(2+)-sensing properties have also been discussed, and log Ks values of about 3.60 and 3.73 were determined. Confocal microscopic images of Caenorhabditis elegans incubated with RhOH were found to show enhanced fluorescent intensity with a Hg(2+) ion, demonstrating the potential application of RhOH for in vivo biological imaging.

Two new series of two-dimensional (2-D) lanthanide–silver heterometallic–organic frameworks with the formula [Ln2Ag(IN)2(BPDC)2(H2O)4]·(NO3)·2H2O (1-Ln) (Ln = Nd 1, Eu 2, Tb 3, and Dy 4) and [Ln2Ag(IN)2(BPDC)2(H2O)2]·(NO3)·2H2O (2-Ln) (Ln = Ho 5, Yb 6, HIN = isonicotinic acid, H2BPDC = 2,2′-biphenyldicarboxylic acid) have been hydrothermally synthesized and characterized by single crystal X-ray diffraction, elemental analysis, IR spectroscopy, thermogravimetric analysis (TGA) and powder X-ray diffraction (PXRD). In the structures of these six compounds, BPDC2− ligands link Ln3+ through their carboxylate groups, resulting in the formation of one-dimensional (1-D) {Ln(BPDC)}n infinite chains. These adjacent chains are further connected to each other via the coordination interaction between Ln3+ and carboxylate groups of IN− ligands, as well as the pillared Ag(IN)2 units, giving rise to 2-D layered structures. Although they have similar secondary building units (SBUs), the whole open frameworks of these two types of HMOFs that may be produced by the lanthanide contraction effect are quite different. Isostructural compounds 1–4 (1-Ln) crystallize in the monoclinic C2/c space group and possess a (6,3)-connected topology containing 1-D hexagonal microporous channels along the c axis, while isostructural compounds 5 and 6 (2-Ln) crystallize in the triclinic P space group and present a 2-D network of (4,4)-connected topology with 1-D rhombic channels along the b axis. Meanwhile, solid-state photoluminescence studies of compounds 1–3 and 6 were also conducted at room temperature and the luminescence intensity of 3 and 6 are found to be sensitive to small molecules.

An efficient method for the synthesis of a wide variety of N-rich heterocycles has been systematically explored. The synthetic protocol involves a solvothermal in situ metal–ligand reaction of pyridine-type Schiff base N-(2-pyridylmethyl)-pyridine-2-carbaldimine (L) with Cd2+ ions, resulting in the efficient formation of nine temperature-dependent CdII-complexes 1–9 supported by six types of N-rich heterocycles L1–6. To the best of our knowledge, both the synthetic strategy with solvothermal in situ CdII-mediated Schiff base-conversion and N-rich heterocycle rings L1–2 as well as cis-L6 are reported for the first time. Meanwhile, plausible in situ formation mechanisms of L1–6 are also proposed.

Four new heterometallic coordination complexes, namely, {[Zn4Ln2(imdc)4(SO4)(H2O)8]·4H2O}n [Ln = Nd (1), Sm (2), Eu (3), Gd (4); H3imdc = imidazole-4,5-dicarboxylic acid], were hydrothermally synthesized by the reactions of Ln2O3 with imidazole-4,5-dicarboxylic acid and ZnSO4·7H2O and characterized by single-crystal X-ray diffraction, infrared spectroscopy (IR), elemental analysis (EA), thermogravimetric analysis (TGA) and powder X-ray diffraction (PXRD). The single-crystal X-ray diffraction analyses reveal that these polymers are isostructural and possess an interesting 3D pillar-layered architecture with 424·64 topology, in which 2D layers constructed by alternately arranged 1D right-/left-handed helical chains of [Zn2(μ5-imdc)]n bridged via dimeric Eu2 units are pillared by μ2-SO42− and μ3-imdc3− anions. The liquid fluorescence of compounds 1–3 at room temperature shows that these complexes are very good chemosensors for I− ion, and the response of the sensor is based on fluorescence quenching of Zn–Ln MOFs by iodine ions.

Five variable dimensional cadmium(II) coordination polymers, {[Cd2(bpy)2(NO3)4·H2O]}n (1), [Cd(2,3-Pydc)]n (2), {[Cd2(2,3-Pydc)(bpy)2(NO3)(H2O)2]·(NO3)·3H2O}n (3), [Cd2(2,3-Pydc)2(H2O)]n (4) and {[Cd(NA)(NO3)(H2O)2]}n (5), have been synthesized by hydrothermal reaction of pyridine-2,3-dicarboxylic acid (2,3-H2Pydc) and 4,4′-bipyridine (bpy) with cadmium nitrate under different temperatures. At 80 °C, the mixture A of a 1-D compound 1 containing only a ligand of 4,4′-bpy and 2-D 36·46·53 topological compound 2 with a single ligand of 2,3-Pydc2− were obtained. At 120 °C or so, the 3-D 64·102 topological compound 3 containing mixed ligands of 2,3-Pydc2− and 4,4′-bpy was assembled. However, as the temperature increased to 170 °C, partial 2,3-H2Pydc in situ decarboxylated into nicotinic acid (HNA) and consequently another mixture B of 3-D 316·423·53·63 topological compound 4 reported previously and 1-D chain-like compound 5 containing NA− were constructed. Meanwhile, the complexes 1–3 and 5 exhibited good luminescent properties.

Six coordination polymers (CPs), namely, [Ag(tmb)]n (1), [Cu(tmb)2(H2O)]n (2), [Eu(HCOO)(tmb)2]n (3), [Ag(bimb)(Hbimb)]n (4), [Cu(bimb)2]n (5) and [Eu(bimb)3]n (6) (Htmb = 4-((1H-1,2,4-triazol-1-yl)methyl)benzoic acid), Hbimb = 4-((1H-benzo[d]imidazol-1-yl)methyl)benzoic acid), have been successfully synthesized under similar solvothermal conditions and characterized by elemental analysis, IR, thermogravimetric analysis and single-crystal X-ray diffraction. 3-D complex 1 presents a binodal (3,6)-connected rutile topology with the Schlafli symbol (42·610·83) (4·62)2. Previously reported complex 2 shows a 3-D framework of pcu topology, in which the inorganic ⋯Cu–O–Cu–O⋯ chains are connected to each other through the tmb− ligands. In 3, Eu(III) atoms are connected by carboxylate groups to form a double-helical chain, which further expands to a 3-D framework of tsi topology with the Schlafli symbol (36·416·56). Complex 4 exhibits a 1-D chain structures which are further connected by O–H⋯O hydrogen bonding and π⋯π interactions to form a 3-D supramolecular framework. Complex 5 features a two-dimensional 44 layer. In 6, Eu3+ ions are bridged by bimb− ligands to form a 1-D three-strand double-helical chain which is further connected by ligands to produce a 2-D layer with a 4·82 topology. The different structural dimensions of the six complexes (1–6) are closely related to the steric effect of the triazole ring or benzimidazole ring in the ligands. Furthermore, the fluorescence properties of 1, 3, 4, and 6 are studied in the solid state at room temperature.

A three-dimensional (3-D) multi-functional mixed valence CuII/CuI-MOF, {[Cu(CuI)2(2-pyzc)2H2O]2·H2O}n (Hpyzc = pyrazine-2-carboxylic acid), has been solvothermally synthesized and successfully characterized by FT-IR spectroscopy, elemental analysis, powder X-ray diffraction, thermal gravimetric analysis (TGA) and single-crystal X-ray diffraction. The structure posesses a 3-D open framework containing 1-D channels and shows a tcj topological network with the Schlafli symbol (43·612)(43)2. This MOF exhibits selective adsorption of CO2/H2 over CH4/N2 and excellent catalytic activity in the oxidation of benzylic compounds and three-component coupling reactions of aromatic alkynes, tosyl azide and diisopropylamine as a cooperative catalyst. The catalyst could be reused several times without significant degradation in catalytic activity.

In this study, pre-mixed poly aluminum chloride (PACl) and super powdered activated carbon (SPAC)/carbon nanotubes (CNT) were employed for the removal of emerging contaminants (ECs) from various water sources. Salicylic acid (SALA), ibuprofen (IBP) and diclofenac (DCF) were the targeted ECs. The synergistic effect of the combined coagulation and adsorption process as well as their individual removal performance are discussed in this paper. The results of the three ECs removal indicate that pre-mixed PACl and SPAC/CNT has a better removal ability compared with PACl or SPAC/CNT alone. The maximum adsorption capacities increase at least 5 times after the addition of PACl, attributed to the charge neutralization and adsorption on the flocs. The removal efficiency of ECs by coagulation improves with the addition of SPAC/CNT as a result of the bridging effect as well as adsorption of ECs by carbon materials. The removal efficiency for these three ECs generally exhibited the following trends: SALA (log P = 1.98) < IBP (log P = 3.84) < DCF (log P = 4.26), indicating that the hydrophobicity of the ECs plays an important role.

Two Schiff base ligands (HL1, HL2) were conveniently synthesised by one-step condensation between pyridine 2-ylmethanamine and 3-ethoxy-2-hydroxybenzenaldhyde (for HL1) or salicylaldehyde (for HL2) as fluorescent sensors for distinguishing sensing of Zn2+ or Cd2+. Both of the two fluorescent sensors present very weak emission at 463 nm (for HL1) or 453 nm (for HL2). For HL1, upon addition of Zn2+, the fluorescence intensity of HL1 enhanced and gradually red shifted to 493 nm with a green emission while addition of Cd2+ only induced enhancement of fluorescent intensity at 463 nm. For HL2, only addition of Zn2+ induced enhancement of fluorescence intensity, presenting a high Zn2+/Cd2+ selectivity. A Zn2+-induced red shift in fluorescent spectra of HL1 could be attributed to twisted intramolecular charge transfer (TICT) from the interaction between the Zn2+ ion and in situ formed ligand L1′ with the twisted structure in compound 1, which is absent in compound 2. The Zn2+/Cd2+ selectivity of fluorescent response for HL2 correlates with the Cd–HL2 and Zn–HL2 coordination bond distances. Obviously, introduction of ethoxyl groups onto the benzene ring as an electron-donating group facilitates the Zn-induced in situ dimerization of HL1 into new ligand L1′ with a twisted molecular structure, further resulting in a red shift of the fluorescence spectra.

Improving the propulsion of artificial micro-nanomotors represents an exciting nanotechnology challenge, especially considering their cargo delivery ability and fuel efficiency. In light of the excellent photocatalytic performance of zinc oxide (ZnO) and chemical catalytic properties of platinum (Pt), ZnO-Pt microrockets with light-enhanced propulsion have been developed by atomic layer deposition (ALD) technology. The velocity of such microrockets is dramatically doubled upon irradiation by 77 mW cm-2 ultraviolet (UV) light in 10% H2O2 and is almost 3 times higher than the classic poly(3,4-ethylenedioxythiophene)-Pt microrockets (PEDOT-Pt microrockets) even in 6% H2O2 under the same UV light. In addition, such micromotors not only retain the standard approach to improve propulsion by varying the fuel concentration, but also demonstrate a simple way to enhance the movement velocity by adjusting the UV light intensity. High reversibility and controllable "weak/strong" propulsion can be easily achieved by switching the UV irradiation on or off. Finally, light-enhanced propulsion has been investigated by electrochemical measurements which further confirm the enhanced photocatalytic properties of ZnO and Pt. The successful demonstration of ZnO-based microrockets with excellent light-enhanced propulsion is significant for developing highly efficient synthetic micro-nanomotors which have strong delivery ability and economic fuel requirements for future practical applications in the micro-nanoscale world.

The removal of acetylene from the industrial feed gas to purify the ethylene is an important and challenging issue. The adsorption-based separation is a more environmentally friendly and cost-effective method compared to the current removal approaches such as partial hydrogenation and solvent extraction, while facing the challenge of developing materials with high C

By application of newly designed ligand 5-(3-(pyridin-3-yl)benzamido)isophthalic acid (H2PBI) to react with Mn(NO3)2 under solvothermal conditions, a 2-fold interpenetrated Mn-based metal–organic framework (Mn-PBI) with rutile-type topology has been obtained. When treated as a precursor by pyrolysis of Mn-PBI at 500 °C, mesoporous MnO/C–N nanostructures were prepared and treated as an lithium-ion battery anode. The MnO/C–N manifests good capacity of approximately 1085 mAh g–1 after 100 cycles together with superior cyclic stability and remarkable rate capacity, which is supposed to benefit from a large accessible specific area and unique nanostructures. The remarkable performances suggest promising application as an advanced anode material.

A microporous Pb-based metal–organic framework (MOF) [Pb(4,4′-ocppy)2]·7H2O (Pb-MOF) has been constructed from 4-(4-carboxyphenyl)pyridine N-oxide and Pb(NO3)2. Structural analysis reveals that the Pb-MOF possesses three-dimensional framework with a one-dimensional rhombic channel. When tested as a lithium-ion battery anode, a reversible lithium storage capacity of 489 mAh g–1 was maintained after 500 cycles at 100 mA g–1 as well as excellent cycling stability. The superior electrochemical performance may be derived from the sustenance of the Pb-MOF framework and compositional features of the organic moiety.

One convenient CdII-mediated C–C/C–N bond-forming strategy toward asymmetric tetra-(2-pyridine)-substituted imidazolidine (L1), the basic framework of several natural products with bioactivity, has been found for the first time. In the reaction of tridentate N3-set neutral pyridine-type Schiff base ligand (L) possessing a [−HCNCH2−] linkage with CdCl2 at 70 °C for 3 days, one two-dimensional 44 topological layer [Cd3L1Cl6]n (1) could be obtained, in which ligand L1 resulted from [3 + 2] C–C/C–N asymmetric coupling dimerization of L. When equimolar amounts of NaSCN and NaNO3 were added to the reaction mixtures, one-dimensional chain [Cd2L1(SCN)Cl3]n (2) and zero-dimensional dinuclear Cd2L1(NO3)4(MeOH) (3) containing the same ligand L1 were also generated under the same reaction conditions, respectively. Obviously, the medium of the Cd2+ ion plays the key role in solvothermal in situ formation of ligand L1. Moreover, new ligand tetra-substituted imidazolidine (L1) could be obtained effectually from all thre...

Four anion-dependent 0D Zn(II)-Yb(III) heterometallic Schiff base complexes, [YbZn2L2(OAc)4]·ClO4 (2), YbZnL2(NO3)3 (3), [(YbL)2(H2O)Cl(OAc)]2·[ZnCl4]2 (4), and YbZnL(OAc)4 (5), were assembled through central metal substitution or reconstruction from homotrinuclear Zn(II) complex {[(Zn(OAc)(H2O)L]2Zn}(ClO4)2·4H2O [1; HL = 2-ethoxy-6-[(pyridin-2-ylmethylimino)methyl]phenol] with different Yb(III)X3 salts [X = ClO4 (2), NO3 (3), Cl (4), and OAc (5)], in which the Zn(II)-sensitized near-infrared luminescent performances in the four complexes 2-5 are closely related to their structural models.

Two zinc(II) complexes with NO- and N2O-set oxime-containing Schiff base ligand of 2-hydroxyimino-N′-[1-(2-pyridyl)ethylidene]propanohydrazone (Hpop), namely [Zn3(pop)2-(CH3OH)2Cl4] (1) and [Zn(pop)Cl]4·(H2O)2 (2), have been successfully synthesized from the reaction of Hpop with ZnCl2 in CH3OH under different temperatures and fully characterized by X-ray single-crystal diffraction, EA and IR as well as TG. At the low temperature, the linear M3L2-type trinuclear Zn(II) compound 1 was obtained, however, the grid-like Zn4L4-type tetranuclear Zn(II) compound 2 was given at the high temperature from the same reactants. Interestingly, compound 1 may be irreversibly transformed into 2 via ring-closed coordination reaction under the high temperature, accompanied by the corresponding changes in fluorescent property.

The first example of 3D heterometallic 4d–4f 2,7-naphthanlenedisulfonate compounds [LnAg2(2,7-NDS)(IN)3] (Ln = Sm (1), Eu (2), Gd (3), Tb (4), Dy(5); 2,7-NDS = 2,7-naphthanlenedisulfonate; IN = isonicotinic acid) has been synthesized via hydrothermal reaction and characterized by single crystal X-ray diffraction, elemental analyses, FT-IR spectroscopy, powder X-ray diffraction(PXRD) and thermogravimetric analyses (TGA). X-Ray structural analysis reveals that compounds 1–5 exhibit same well-organized 3D coordination frameworks that are built up by 2D elliptical cylinder shaped [LnAg2(2,7-NDS)(IN)3] layers which are constructed by 1D anionic chains [Ln(2,7-NDS)(IN)3]2 − linking the adjacent Ag(I) ions, and [LnAg(μ2-O)2] units, possessing a 7-connected topology with the Schlafli symbol of {33;411;56;6}. Furthermore, the luminescence properties of compounds 2 and 4 and the magnetic properties of compounds 3 and 5 were investigated.

Spinel structure transition metal oxides have been developed as promising anode materials for Lithium ion batteries (LIBs). Herein, an inverse spinel SnFe2O4 (SFO) nanoparticles using a simple coprecipitation method, and then a novel SnFe2O4@nitrogen-doped carbon composite (SFO@NC) using poly-dopamine as the carbon source are synthesized, and used as anode materials. SFO@NC delivers high initial charge/discharge capacities of 1140.4/2148.2 mAh g−1 at a current density of 0.2 A g−1, and maintains a high reversible capacity of 1030 mAh g−1 after 300 cycles, also exhibits excellent rate performance with 669.6 mAh g−1 at the current density of 2.0 A g−1. The Li+ storage performance in SFO@NC is far superior to those of pure SFO, which is attributed to the nitrogen doped carbon layer can supply more active sites, enhance the conductivity of the electrode and buffer the volume change of SnFe2O4 during lithium ion in-/deinsertion. Moreover, the Li+ storage kinetics in SFO and SFO@NC have been investigated by measuring cyclic voltammetry (CV) at different scan rates and the electrochemical impedance spectroscopy (EIS) at different temperatures. The results indicate that the Li+ storage behavior of SFO@NC is a combination of capacitive and diffusion-controlled processes, and the barrier energy for the Li+ transport in the SEI film (ΔEa,SEI), the activation energy of the charge transfer in the double layer (ΔEa,CT), and the diffusion activation energy of Li+ in the anode (ΔEa,D) are determined to be 35.05, 52.63 and 58.9 kJ mol−1 with the SFO@NC; and 43.81, 54.75 and 42.6 kJ mol−1 with the pure SFO, respectively. Obviously, the lithium ions are easily intercalated and deintercalated in the SFO@NC anode in kinetics.

The organic compound, 5, 6-dicarboxy-3H-benzoimidazol-1-ium nitrate (Hdcbii·NO3) (1), was synthesized by the reaction of 1H-benzoimidazole-5, 6-dicarboxylate (Hbidc) with nitric acid under hydrothermal conditions. The crystal structure of the compound shows abundant hydrogen bonds and π···π stacking interactions revealed by X-ray single crystal diffraction and FT-IR spectroscopy. This compound has high selectivity for ferric (Fe3+) ions in aqueous solution and shows strong potential for application as a fluorescent probe for ferric ions.

Two d10 metal–organic frameworks (MOFs) with 1-(4-carboxyphenyl)-1,2,4-triazole (Hcpt), namely [Zn(cpt)2]n(1) and {[Cd(cpt)2] · 2DMF}n (2), have been solvothermally synthesized by fine control over synthetic conditions, and structurally characterized. The results reveal that compound 1, once reported in literature, crystallizes in the acentric Cc space groups, in which the tetrahedral Zn2 + center in 1 coordinates to two triazole nitrogen atoms and two carboxylate oxygen atoms from four μ2 − η1:η1 bridging cpt− ligands, leading to a noncentrosymmetric 5-fold interpenetrating diamondoid 3-D network. On the other hand, new compound 2 has orthorhombic and space group Pbc21, in which distorted octahedral Cd2 + center in 2 coordinates to two triazole nitrogen atoms and two carboxylate oxygen atoms from four μ2 − η1:η1:η1 bridging cpt− ligands, resulting in an interesting 4-fold interpenetrating diamondoid 3-D network structures containing 1-D channels with a cross section of 9.5 × 9.3 A. Considering their different topological structures, the gas adsorption experiments of 2 were carried out, and the results show that 2 presents a selective adsorption of CO2 over N2/H2. Moreover, the fluorescent properties of compounds 1 and 2 were also studied.

Restricted rotation of the ortho sulfinyl groups directs the trans ortho-substituted bis-sulfoxide (3) to adopt right-handed (P) or left-handed (M) conformation and thus produces symmetric atropisomeric (R,R)-3/(S,S)-3 and asymmetric atropisomeric enantiomers (R,S)-3, respectively. (R,S)-3 exhibits spontaneous resolution and crystallizes as a conglomerate (P,R,S)-3/(M,R,S)-3 with a homochiral supramolecular helix (P/M-helix) conformation.

Two new complexes based on 4-(benzimidazol-1-ylmethyl)benzoic acid (HL), (Sm2L6·H2O)n (1) and (LuL3)n (2), have been synthesized under the solvothermal condition and characterized by single-crystal X-ray diffraction, X-ray powder diffraction (PXRD), thermogravimetric analysis (TGA) and elemental analysis (EA) and IR spectra. The results show that both complexes are isomorphous and possess 2-D pillar-chained frameworks, consisting of 1-D triple-stranded double-helical (PPM/MMP) [Ln(η2-O)(μ2-OCO)2]n (Ln = Sm(1), Lu(2)) motif as chain and μ3-(η1:η1:η1)-bridging ligand L− as pillar, though they have different space groups of triclinic P-1 for 1 and monoclinic P21/c for 2. Two complexes represent the first example of 2-D lanthanide compound containing 4-(benzimidazol-1-ylmethyl)benzoic acid as the sole ligand. Additionally, the photoluminescent property of 1 is also discussed.

Three 3D Ln(III)–Zn(II) 3d-4f heterometallic coordination polymers (HCPs) constructed from the coligands 3-amino-1H-1,2,4-triazole and oxalate, {[Ln2Zn19(atz)18(ox)9(Cl)8]·17H2O}n(Ln = Eu 1, Gd 2, Tb 3, Hatz = 3-amino-1H-1,2,4-triazole, ox = oxalic acid) have been synthesized under hydrothermal conditions and characterized by elemental analysis, FT-IR, TG analysis and X-ray diffraction. X-ray diffraction analysis reveals that these complexes are isostructural and feature 3D pillar-layered coordination frameworks constructed by the linkages of 2D layers and 1D zigzag chains, possessing a 5-nodal net topology with Schlafli symbol of {32;52;62}3{33;44;57;65;72}6{33;45;55;6;7}6{36;415;56;6}2{53}4. In addition, the magnetic property of 2 and the luminescence properties of 1 and 3 were also investigated.

Three isostructural lanthanide complexes, [Ln2(H2O)4(DMSO)](CuI)4(Ina)4(ox)[HIna = isonicotinic acid; H2ox = oxalic acid; Ln = Pr(1), Sm(2), Eu(3)], have been synthesized under the solvothermal condition and characterized by single-crystal X-ray diffraction, X-ray powder diffraction (PXRD), thermogravimetric analysis (TGA) and elemental analysis (EA) and IR spectra. Complexes 1–3 present 2-D pillar-chained frameworks and consist of two distinct chain-like motifs of inorganic [Cu4I4]n cluster chains and organic Ln-carboxyl-oxalic [Ln2(μ2-Ina)2(Ina)2(μ2-ox)]n chains. The 13C NMR of HIna indicates ox2 − in 1–3 is generated by the in situ decomposition of HIna. Additionally, the photoluminescent properties of 1–3 are also discussed.

A series of Ln(III)-Ag(I) 4d–4f heterometallic coordination polymers [LnAg(oba)2(H2O)]n (Ln = Dy 1, Ho 2, Er 3) have been synthesized under hydrothermal reactions of 4,4′-oxybis(benzoicacid) (H2oba) with Ln(NO3)3 · 6H2O and AgNO3 at 180 °C. All complexes are isostructural with 3D networks expanded from 1D zigzag chains and 2D layers. In addition, the luminescent property of compound 1 was investigated in the solid-state at room temperature.