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[Display omitted] To fulfill the growing energy demands, electrochemical energy storage (EES) technologies have played a pivotal role in the field of renewable energy storage and power supply. Metal-organic framework (MOF) materials have attracted great attention due to their unique porous structure and associated multifunctional properties. During the processing of MOF materials to obtain the corresponding derivative materials, heterogeneous elements are introduced as mediators and influence the structure and properties of the final obtained materials. This review focuses recent research progress in the field of EES based on heterogeneous elements doped MOF derivatives (H-MOFs), and proposes the heterogeneous element doping and design synthesis strategies in the construction of H-MOFs. The application of H-MOFs in alkali metal batteries, lithium-sulfur batteries, supercapacitors, and other devices were systematically summarized, and the mechanism of its performance enhancement was analyzed. Finally, the current status, possible deficiencies and unresolved issues are pointed out, and future research directions and contents are discussed. [ABSTRACT FROM AUTHOR]

• Coordination polymer {[Mn 2 (BTIA) 2 (H 2 O)]·7H 2 O} n was synthesized solvothermally. • The structure is a 4,8-connected 3D framework. • Antiferromagnetic (AF) interactions exist between Mn2+ ions. • The porous Mn-MOF shows a small uptake capacity for CO 2. One three dimensional metal organic framework {[Mn 2 (BTIA) 2 (H 2 O)]·7H 2 O} n (Mn-1) was synthesized from the multidentate organic linker 4,6-bistriazole isophthalic acid (H 2 BTIA) and MnCl 2 ·4H 2 O under solvothermally condition. The structure of 1 exhibits as a three-dimensional framework fabricated by the binuclear subunits [Mn 2 (COO) 2 (H 2 O)] and the organic linkers (H 2 BTIA). Topologically, it displays a binodal framework with Schläfli symbol (44 · 62) 2 (416 · 612), which contains one dimensional channels along a direction. The magnetic behavior of Mn-1 was investigated, which discloses the antiferromagnetic (AF) interactions between Mn2+ ions with the coupling constant J = −1.38 cm−1. In additin, the porous Mn-MOF shows a small uptake capacity for CO 2. [Display omitted] One 3D coordination polymers {[Mn 2 (BTIA) 2 (H 2 O)]·7H 2 O} n have been successfully obtained based on multidentate linker 4,6-bistriazole isophthalic acid (H 2 BTIA). The structure of 1 fabricated into a 3D MOF by the binuclear subunits [Mn 2 (COO) 2 (H 2 O)] and the organic connectors (H 2 BTIA). It displays a binodal framework with Schläfli symbol (44 · 62) 2 (416 · 612) with 1D channels along a direction. The magnetic behavior of Mn-1 discloses AF couplings between Mn2+ ions in every subunit. [ABSTRACT FROM AUTHOR]

[Display omitted] • The work provides a rapid preparation method for defective HKUST-1 with hierarchical micropores and mesopores and Cu1+/Cu2+ mixed-valence sites. • Defective HKUST-1 exhibited specific loading of silibinin A&B with larger molecules from silymarin within 5 min, and high separation efficiency with 91.2% purity after primary separation. • The site competition mechanism for specific recognition and loading of active monomers into mesopores of defective MOF was elucidated at molecular level. • Silibinin A&B preferentially acted on Cu2+ and Cu1+ clusters with the highest binding energy via hydrogen and coordination bonds, respectively. • The separation approach by defective MOF is easy to operate, and requires no specific equipment. Discovering and separating active monomers from natural products is an efficient way to develop new drugs, but faces the difficulty in complex and time-consuming separation process. Metal-organic frameworks (MOFs) are considered a promising separation strategy due to their molecular recognition properties, but their microporous nature poses challenges for capturing most natural compounds with molecule sizes larger than 20 Å. For the first time, this study proposed a simple and efficient approach to separate active monomeric components with larger diameters from structurally similar natural compounds by defect modulation strategy. In this study, defective HKUST-1 with hierarchical microporous/ mesoporous structures and Cu1+/Cu2+ mixed-valence sites was rapidly synthesized. The defective MOF demonstrated specific loading of silibinin A&B from silymarin containing seven structurally similar flavonoids within 5 min, and high separation capacity with the purity of ∼91.2% after primary separation. FTIR, XPS, and DFT calculation revealed the site competition mechanism for specific recognition and loading, where silibinin A&B preferentially acted on Cu2+ and Cu1+ clusters with the highest binding energy via hydrogen and coordination bonds, respectively. Compared to traditional separation techniques, the separation approach via defective MOF shows multiple advantages including high specificity, high separation efficiency, and easy to operate. [ABSTRACT FROM AUTHOR]

• Two coordination polymers {[Co(TIA)(H 2 O) 2 ]·0.25H 2 O} n and {[Mn(TIA)(H 2 O) 2 ]·0.5H 2 O} n were successfully obtained. Both of them are as 3,3-linked two-dimensional layers. The static and/or dynamic magnetic characteristics of the two polymers were investigated.Graphical Abstract Two coordination polymers {[Co(TIA)(H 2 O) 2 ]·0.25H 2 O} n (Co-1), and {[Mn(TIA)(H 2 O) 2 ]·0.5H 2 O} n (Mn-2) were obtained solvothermally based on the exquisite combination of multidentate rigid linker 5-(1H-1,2,4-triazol-1-yl) isophthalic acid (H 2 TIA) and M(NO 3) 2 ·6H 2 O (M = Co(II), Mn(II)). The structures of 1-2 are both as 3,3-linked two-dimensional layers, which assemble into three dimensional supramolecular microporous structures by O−H⋅⋅⋅O hydrogen bonds. In addition, the static and/or dynamic magnetic characteristics of the two polymers were investigated. [Display omitted] [ABSTRACT FROM AUTHOR]

• The Zn-MOF characters as a (32,4-c net) 3D skeleton. It contains one-dimensional channels. Zn-1 exhibits excellent adsorption behavior of anionic dyes CR2–, MO–, and EBT–. The adsorption results were simulated by AIMD simulations. It also displays good separation performance of a variety of anionic and cationic dyes. One porous metal−organic framework {[Zn(TIA)(DPE) 0.5 ]·3DMF} n (Zn-1) was successfully constructed under solvo-thermal reaction of Zn(NO 3) 2 ·6H 2 O with multifunctional ligand 3-(4H-1,2,4-triazol-1-yl)-isophthalic acid (H 2 TIA) and linear bridge dipyridyl ethylene (DPE). Polymer Zn-1 characters as a (32,4-c net) 3D skeleton containing uni-dimensional channels, which results in its high efficient adsorption behavior of anionic dyes CR2−, MO–, and EBT–. Especially for the large-size CR2−, it shows the most rapid removal rate. More importantly, it realized good separation effects of mixed anionic and cationic dyes (CR2−/MB+ and MO–/MB+). Such excellent performances of dye adsorption and separation are mainly caused by the uni-dimensional channels of MOF Zn-1 and supramolecular interactions between guest-host, which was supported by ab initio molecular dynamics (AIMD) simulations. Synopsis Using a bifunctional ligand 3-(1H-1,2,4-triazol-1-yl)isophthalic acid (H 2 TIA) and a linear bridge dipyridyl ethylene (DPE), one porous Zn-MOF (Zn-1) has been successfully obtained. The framework of Zn-1 characters as a (32,4-c net) 3D skeleton containing large size uni-dimensional channels. In addition, Zn-1 exhibits excellent adsorption behavior of anionic dyes CR2−, MO–, and EBT–, which was confirmed by ab initio molecular dynamics (AIMD) simulations. Further, the adsorbed anion dyes can be readily set free in saturated NaCl aqueous solution. What's more, it displays good separation performance of a variety of anionic and cationic dyes, such as CR2−/MB+ and MO–/MB+. [Display omitted] [ABSTRACT FROM AUTHOR]

Metal organic frameworks (MOFs) are an ideal platform to construct electroactive materials for electrochemical energy storage due to their unique structure and excellent porosity. However, it is still a challenge to make full use of their structural advantages to rationally design multi-component electrode materials for high-performance supercapacitors. Herein, carbon-coated spherical sulfide nanoparticles are reported by simultaneous carbonization and sulfurization using bimetal/monometal-based MOFs as the precursors. The NiCo 2 S 4 @C and NiS@C composite nanoparticles have excellent electronic conductivity, large porosity and high electrochemical reaction activity. In particular, the bimetallic NiCo 2 S 4 @C-based electrode exhibits a high specific capacity of 948.9 C g−1 at 1 A g−1. Furthermore, a hybrid supercapacitor assembled with NiCo 2 S 4 @C as the positive electrode and activated carbon as the negative electrode achieves a high energy density of 43.8 Wh kg−1 with power density at 799.1 W kg−1, and a capacitance retention rate of 81.9% after being subjected to 5000 cycles of charge and discharge. The results suggests using MOFs as precursors is a feasible strategy to synthesize advanced sulfide-based multi-component materials for electrochemical energy storage. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] • A simple and efficient "induced dehydration strategy" was proposed to prepare Mannitol@CaCl 2 MOF with crystal defects (DEMOF). • Lattice vacancy and macrostructural defects were successfully introduced into Mannitol@CaCl 2 MOF while preserving its skeleton structure. • DEMOF presented much better mechanical properties than the original MOF at the powder level. • Defect structure increased plasticity, decreased brittleness, and improved compressibility, resulting in DEMOF tablets with much higher tensile strength that met the criteria for direct compression excipients. The mechanical properties of solid pharmaceutical excipients are important for assisting drug tables production, and they determine the quality of the drug tablets. The purpose of this study was to explore the potential and mechanism of crystal defect engineering to improve the mechanical properties of Mannitol@CaCl 2 MOF, a pharmaceutical excipient with metal–organic framework (MOF) structure designed and prepared in our previous study. In this study, a simple and efficient "induced dehydration strategy" was proposed to prepare Mannitol@CaCl 2 MOF with crystal defects (DEMOF). SEM, TEM, HRTEM, PXRD, FTIR, DSC-TGA, and N 2 adsorption–desorption isotherm revealed the successful introduction of lattice vacancy and macrostructural defects while preserving MOF's skeleton structure. Tabletability profiles indicated that DEMOF presented much better mechanical properties than the original MOF at the powder level. On single crystal and atomic scales, nanoindentation and DFT calculations revealed that the defect structure increased plasticity, decreased brittleness, and improved compressibility, resulting in DEMOF tablets with much higher tensile strength that met the criteria for direct compression excipients. The achieved performance modification illustrated the capability of defect engineering to tune mechanical properties of MOFs, and the Mannitol@CaCl 2 DEMOF exhibited great potential to serve as a new direct compression pharmaceutical excipient. [ABSTRACT FROM AUTHOR]

Natural products often contain a large number of structurally similar compounds, however, from which the isolation of monomer compounds is complex and time-consuming. In this study, for the first time, a Zr-based metal-organic framework (MOF), UiO-66, was used for the separation of three isoflavones (genistein (GEN), puerarin (PUE), and daidzein (DDZ)) with similar structures. UiO-66 was demonstrated to have a distinct high adsorption capacity (q e , 105.42 ± 2.36 mg/g) for GEN with high separation factors from PUE (α, 35.52 ± 1.22) and DDZ (α, 7.41 ± 0.76), dramatically increasing the purity of GEN from ∼33–92% after primary separation. According to SEM-EDS and XPS characterizations together with RDF analysis, GEN and PUE were adsorbed on the surface of UiO-66 at the same dominant Zr cluster site (O...Zr), while DDZ was bound onto the inferior site via weak hydrogen bonding (H...O), indicating the separation of GEN from PUE was in a competitive manner, while the separation from DDZ was selective. For these three drugs, their adsorption kinetics and adsorption isotherms conformed Pseudo-second-order kinetic model and Langmuir model, respectively, indicating that the monolayer adsorption of isoflavones on UiO-66 surface was the dominant mechanism. The thermodynamic study demonstrated that both adsorptions of GEN and PUE were spontaneous (Δ G 0 < 0), whereas the DDZ adsorption is non-spontaneous (Δ G 0 > 0). Compared to traditional separation techniques, this study provided a simple and efficient approach to isolate structurally similar compounds from natural products in drug discovery. [Display omitted] • UiO-66 can effectively separate GEN from three structurally similar isoflavones(GEN, PUE, and DDZ). • The adsorption of GEN and PUE on UiO-66 was spontaneous, whereas that of DDZ was non-spontaneous. • GEN was separated from PUE and DDZ in a competitive and selective manner, respectively. • MOF adsorption is a promising approach for effectively separating similar structural natural compounds. [ABSTRACT FROM AUTHOR]

Self-assembly of Ca 2+ , Zn 2+ and 4,5-imidazoledicarboxylic acid (H 3 imdc) via hydrothermal conditions under controlled pH affords three new and unusual heterometallic metal–organic frameworks (MOFs): [Ca 2 Zn 2 (imdc) 2 (Ac)(OH)(H 2 O)] ( 1 ), [CaZn 2 (imdc) 2 (im) 2 (H 2 O) 2 ]·1.8H 2 O ( 2 ), [CaZn(Himdc) 2 (H 2 O)] ( 3 ), (Ac = acetate; im = imidazole) and characterized by elemental analysis, IR, powder X-ray diffraction (PXRD), and single-crystal X-ray diffraction. X-ray single-crystal structural analyses revealed that Zn(II) ions all coordinate with two imdc ligands no matter whether it is in a five or six coordination environment, while Ca(II) ions in 1 – 3 are all eight-coordinated. The Zn(II) ion with imdc ligands makes up a 2-D layer in 1 , 1-D chain in 2 , and 0-D elongated bridge in 3 , respectively, which further connected the Ca(II) ion with the carboxylate oxygen atoms to form 3-D MOFs in 1 , 2 , a 2-D framework in 3 . The total Schäfli symbol of the topologies of the heterometallic complexes 1 – 3 are {4;6 2 }{4;6 4 ;8}{4 2 ;6 3 ;8 5 }{4 3 ;6 2 ;8}{4 4 ;6 4 ;8 2 }{4 4 ;6 5 ;8 5 ;10}{4}{6 2 ;8}, {12 3 }{12} 2 {4;12 2 }{4;12 5 } and {4;8 2 }{4 2 ;6;8 2 ;10}{4 6 ;6 4 }{8}, respectively. The three Ca(II)/Zn(II) heterometallic complexes showed blue emission arising from intraligand π–π ∗ transition. [ABSTRACT FROM AUTHOR]

A new three-dimensional lanthanide–manganese metal–organic framework [Gd 2 Mn 3 (PZTC) 4 (H 2 O) 12 ]·5H 2 O (PZTC = 2,3,5-Pyrazinetricarboxylate) has been synthesized under hydrothermal conditions and characterized by IR, elemental analyses, and X-ray diffraction. Single-crystal X-ray diffraction shows that Gd 3 + and Mn 2 + ions are linked together to form a porous 3D Gd–Mn MOF by the alternative arrangement of two kinds of PZTC 3 − ligands. Taking the Gd, Mn and PZTC as node, the Schläfli symbol of the topology can be expressed as {4;8 2 } 2 {4 2 ;6} 2 {4 2 ;8 4 } 2 {4 3 ;6;8 4 ;10 2 } 2 {8}. Magnetic study indicates the magnetic coupling between two Mn 2 + ions through double monatomic carboxylate–oxo bridges is weak antiferromagnetic, while that between Gd 3 + and Mn 2 + ions through the carboxylate group in syn – anti -bridging mode is negligible. [ABSTRACT FROM AUTHOR]

• Carbonized polymer dots were first used as ECL luminophores. • Cathodic carbon-based ECL excitation potential as low as -0.95 V for the first time. • The nanoconfinement enhancement of ZIF-8 significantly augments the ECL response. • Fe 3 O 4 as a co-reaction accelerator involved in the redox reaction remarkably boosted the ECL signal. • The established immunosensor exhibited a low detection limit of 126 fg/mL for CYFRA21–1. Developing novel luminophores for electrochemiluminescence (ECL) that could operate smoothly under low-potential excitation while incorporating creative enhancement strategies is a challenging but very attractive initiative to achieve sensitive detection of disease markers. Herein, carbonized polymer dots (L-CPDs) with low cathode excitation potential were successfully synthesized and used for dual amplified sensitive electrochemiluminescence immunoassay of cytokeratin 19 fragment antigen 21–1 (CYFRA21–1). l -CPDs were first used as ECL luminophores and have an unprecedentedly low excitation potential of -0.95 V that has not been equipped for other cathodic carbon-base dots, avoiding side reactions, bioactive damage and electrode polarization due to high potential, thus obtaining excellent sensor performance. In addition, zeolitic imidazolate framework-8 (ZIF-8) synthesized at room temperature as a nanoconfinement carrier encapsulated l -CPDs and reduced the non-radiative energy loss of the luminophore, which led to substantially improved the ECL signal. The ECL efficiency of the encapsulated luminophores is 2.7 times higher than that of monomeric l -CPDs at the same mass concentration. Platinum composite iron oxide (Fe 3 O 4 /Pt) was used as a co-reaction acceleration platform to strengthen the ECL response. The sandwich ECL immunosensor fabricated achieved sensitive detection of CYFRA21–1 in the detection range of 150 fg/mL–110 ng/mL with a detection limit of 126 fg/mL. In conclusion, this work provides a consideration direction of developing ideal luminophores complemented by amplification strategies in ECL systems construction to achieve accurate and sensitive detection of targets. [Display omitted] [ABSTRACT FROM AUTHOR]

In this work, Ru(bpy) 3 2+ encapsulated in metal–organic frameworks (MOFs) UiO-67 (Ru(bpy) 3 2+ /UiO-67) as luminophor was easily prepared and firstly applied in constructing an electrochemiluminescence (ECL) immunosensor to efficiently estimate diethylstilbestrol (DES). The competitive method-based ECL immunosensor platform was fabricated by amino-silicon dioxide which possesses large surface area. The poriness of UiO-67 was splendid so that Ru(bpy) 3 2+ could be easily encapsulated. Ru(bpy) 3 2+ /UiO-67 with excellent ECL luminescence signal existed large specific surface area for easily labeled with antibodies. DES competed with bovine serum albumin-diethylstilbestrol (BSA-DES) for binding to antibody-specific sites in the constructed immunosensor. However DES was micromolecule, which was easier to bond to antibodies than BSA-DES. The ECL signal was gradually decreases with the increase of the concentration of DES. Under optimal conditions, the proposed immunosensor exhibited a wide linear range from 0.01 pg mL −1 to 50 ng mL −1 with a low detetion limit of 3.27 fg mL −1 (S/N = 3). The novel fabricated immunosensor with interference immunity and high stability may cause an attractive approach for the other targets determination. [ABSTRACT FROM AUTHOR]

The successful application of electrochemiluminescence (ECL) in immunoassay for clinical diagnosis requires improving sensitivity and accuracy. Herein was reported an ECL analytical model based zinc-based metal-organic frameworks of ruthenium hybrid (RuZn MOFs) as the signal emitter. To enlarge the output difference, the quenching effect of three different noble metal nanoparticles included palladium seeds (Pd seeds), palladium octahedrons (Pd oct), and Pt-based palladium (Pd@Pt oct) core-shell were researched. Among them, Pd@Pt oct core-shell possessed higher activity and improved durability than Pd-only (NPs), they could load more protein macromolecules amicably and stabilized in the analysis system. Furthermore, since the charge redistribution owing to the hybridization of the Pt and Pd atoms in Pd@Pt oct , it could generate the electron flow maximumly from the emitter RuZn MOFs to Pd@Pt oct and result in the enhancement of quenching ECL. And the UV absorption of noble metal nanoparticles overlapped with the ECL emission of RuZn MOFs to varying degrees, which caused the behavior of resonance energy transfer (RET) reaction at the same time. This would greatly promote the sensitivity of this ECL system compared with the traditional single quenching mechanism. Based on this, a signal-off immunsensor was constructed to sensitive detection of D-dimer with linearity range from 0.001 to 200 ng mL−1, limit of detection (LOD) was 0.20 pg mL−1 and provide a further theoretical basis for the clinical application of ECL technology. [Display omitted] • RuZn MOFs as luminophor possessed ultra-stable and ultra-efficient ECL emission. • The quenching of noble metals in different crystal states on Ru/Zn MOFs was studied. • Pd@Pt core-shell was proved to obtain the maximum difference of signal output. • The ECL sensor realized ultra-sensitive detection of D-dimer (LOD: 0.20 pg mL−1). [ABSTRACT FROM AUTHOR]

The Dy-MOF@PU sponge can successfully carry out oil–water separation and W/O emulsion separation. To intuitively reveal the separation mechanism of the Dy-MOF@PU sponge for the emulsion, a hypothetical separation process was made. [Display omitted] • Lanthanum-based Dy-MOF was used to decorate 3D PU sponge. • Dy-MOF-F@PU sponge was successfully synthesized by a simple sedimentation method. • Explore the effect of method synthesis on the morphology and hydrophobicity. • Modified sponge with excellent mechanical flexibility, durability and repeatability. Leakage of industrial oil and organic solvents seriously harms environment and ecology yet demanding highly efficient and durable materials for oil–water separations. In this work, ultra-light and highly flexible polyurethane (PU) sponges were engineered to 3D oil–water separators by coating the dysprosium metal organic framework (Dy-MOF) onto the surfaces of the PU frames. Through a facile impregnation, the Dy-MOF was attached to the full frames of the sponges. Consequently, liquid contact surfaces were extended from these on top layers to the whole rack. Superhydrophobicity with water contact angles up to 152.08° and lipophilicity enable continuous separations of dichloromethane from water through the resulted Dy-MOF@PU sponges in a continuous mode. The modified sponges own high gravimetric absorption capacities for oil and organic solvents, and high resistances to temperature variations, corrosive solutions, and mechanical abrasions, thanks to the well-connected and stable superhydrophobic/supportive interfaces. An efficient separation was successfully piloted for oily wastewater consisting of water-in-oil emulsions stabilized by surfactants, demonstrating the potential of practical water treatment of Dy-MOF@PU in complex environments. Mechanism leading to superior oil–water separation capability was studied and inferred as the combined effects of the physical and chemical properties arisen from the stable Dy-MOF and flexible but porous matrix. [ABSTRACT FROM AUTHOR]

[Display omitted] • Hydrophilic, electronegative and porous Ag-MOF was successfully synthesized. • Ag-MOF doped membranes improved the flux and separation property for dye and salt. • Modified membranes exhibited a strong anti-bacterial property for bacteria. Biofouling was a considerable issue in the water treatment by membrane technology. In this study, high anti-bacterial property Ag-MOF was synthesized followed by embedding into polyamide layer with vacuum-assisted interfacial polymerization process to prepare an Ag-MOF incorporated membrane. The successful preparation of Ag-MOF and membranes was verified by FT-IR, FESEM, XPS, XRD, BET, zeta potential and contact angle test. On account to the strong hydrophility, porous structure, electronegativity and antibacterial property of Ag-MOF, modified membranes showed excellent performance for dyes, salts and bacteria. The water permeability of modified membranes was increased from 9.2 to 14.3 L m-2h−1 bar−1 and the rejection rate of MO, MB and RB of the optimum membranes were 95.4%, 87.8% and 99.3%, respectively. The rejection rate of Na 2 SO 4 and MgSO 4 were increased from 54.0% and 36.6% to 84.1% and 73.1%. The sterilization rate of modified membranes to E. coli and S. aureus both exceeded 99%. The leaching test of Ag+ evaluated the potential mechanism of anti-bacterial property. Moreover, dynamic bio-fouling test were used to detect the actual status in the filtration process. Those results suggested that modified membranes showed a strong resistance to bio-foulants thus enlarged the scope of application of membranes for water treatment. [ABSTRACT FROM AUTHOR]

[Display omitted] • The Li-TFSI was encapsulated in the NH 2 -MIL-101, preventing from attack of water. • The regular oxidation process of doped devices can be performed in an ambient condition. • Amino functionalized Li-TFSI@NH 2 -MIL-101 could inhibit the ion migration of Pb2+. • This approach realizes an enhanced stability for 10-fold that of conventional devices. Lithium bis(trifluoromethanesulfonyl)imide (Li-TFSI) is generally regarded as a conventional p-dopant for classical hole transport material Spiro-OMeTAD, which improves the hole mobility and conductivity of hole-transporting layer (HTL). However, the hygroscopic Li-TFSI would absorb moisture and accelerate the degradation of perovskite film, causing a decline in the long-term stability of perovskite solar cells (PSCs). Herein, a novel dopant Li-TFSI endohedral metal–organic frameworks (namely Li-TFSI@NH 2 -MIL-101) is constructed for reducing the amount of Li salt and resisting the attack from water molecules. With a significantly decreased Li salt loading mass, the optimal power conversion efficiency (PCE) of 19.01% is achieved for Li-TFSI@ NH 2 -MIL-101 doped PSCs, which is comparable to that of conventional devices (19.23%). Furthermore, the strong interaction between ammonium groups (–NH 2) and uncoordinated Pb2+ ions would passivate the trap states and inhibit ion migration at perovskite/hole transport layer interface, which further improve the device stability. Importantly, this approach realizes an enhanced stability for approximately 10-fold that of conventional devices at the preliminary stage (time to reduce to 90% of initial PCE). The Li-TFSI@NH 2 -MIL-101 doped PSCs display impressive property stability retaining over 85% of the optimal PCE after 3600 h storage in ambient environment (room temperature and RH ≈ 40%). [ABSTRACT FROM AUTHOR]

Neuron-specific enolase (NSE) is the preferred marker for monitoring small cell lung cancer and neuroblastoma. We devised a dual-signal ratiometric electrochemiluminescence (ECL) sensing strategy for sensitive detection of NSE. In this work, Ru (bpy) 3 2+ functionalized zinc-based metal-organic framework (Ru-MOF-5) nanoflowers (NFs) with plentiful carboxyl groups provide an excellent biocompatible sensing platform for the construction of immunosensor. Importantly, Ru-MOF-5 NFs possess stable and efficient "dual-potential" ECL emission of cathode (−1.5 V) and anode (1.5 V) in the existence of co-reactant K 2 S 2 O 8. Simultaneously, the cathode ECL emitter ZnO-AgNPs are employed as the secondary antibody marker, whose participation amplify the cathode ECL signal as well attenuate the anode ECL emission of Ru-MOF-5 NFs. By monitoring the ECL dual-signal of −1.5 V and 1.5 V and calculating their ratios, a ratiometric strategy of quantified readout proportional is implemented for the proposed immunosensor to precise analyze NSE. Based on optimization conditions, the ECL immunosensor displays the wide linear range of 0.0001 ng/mL to 200 ng/mL and the minimum detection limit is 0.041 pg/mL. The "dual-potential" ratiometric ECL immunosensor effectively reduces system error or background signal by self-calibration from both emissions and improves detection reliability. The dual-signal ratiometric strategy with satisfactory reproducibility and stability provides further development possibilities for other biomolecular detection and analysis. [Display omitted] • The single luminophore Ru-MOF-5 NFs showed "dual-potential" ECL emission. • The "dual-potential" of ECL emission was cathode (−1.5 V) and anode (1.5 V). • ZnO-AgNPs acted as both cathodic luminophore and anodic quencher. • The ratiometric immunosensor provided a novel strategy for NSE detection. [ABSTRACT FROM AUTHOR]

• Ultrasensitive electrochemical aptasensor was fabricated for detecting Pb2+. • AuPd@Fe-MOFs labeled DNA was firstly applied to produce the electrical signal. • Au@MoS 2 /rGO was utilized as sensing platform to construct the aptasensor. • The aptasensor displayed low detection limit of 0.07 pmol/L for Pb2+ detection. In this work, an electrochemical aptasensor was proposed by using gold-modified molybdenum disulfide/reduced graphene oxide (Au@MoS 2 /rGO) nanocomposite and gold-palladium (AuPd)-modified MIL-88 (Fe) metal-organic frameworks (AuPd@Fe-MOFs) for sensitive detection of lead ions (Pb2+). The 8–17 DNAzyme consisting of a substrate strand (Apt1) and a catalytic strand (Apt2) was used to construct the aptasensor. Au@MoS 2 /rGO nanocomposite was applied as the sensing platform to immobilize the mercapto-group-labeled Apt1. Meanwhile, AuPd@Fe-MOFs was employed to label Apt2, which showed excellent catalytic ability toward H 2 O 2. In the presence of Pb2+, the Apt1 of the DNAzyme was catalytically cut off, decreasing the amount of AuPd@Fe-MOFs. The current response was correlated to the Pb2+concentration, thereby achieving Pb2+ detection. Under the optimal experimental conditions, the fabricated aptasensor showed a highly linear response for Pb2+ in the range from 5.0 pmol/L to 2.0 μmol/L, with a detection limit of 0.07 pmol/L. Additionally, the proposed electrochemical aptasensor exhibited excellent selectivity, stability and reproducibility. Moreover, the proposed aptasensor demonstrated good performance in real water sample analysis, making it promising for use in Pb2+ detection in environmental monitoring. [ABSTRACT FROM AUTHOR]

• Highly water-stable and negatively charged UiO-66 TFC membrane was constructed. • The TFC membrane showed high permeability and selectivity for dye and antibiotic. • Antifouling property of UiO-66 TFC membrane presented FRR values higher than 92%. • Size exclusion and electrostatic interaction of UiO-66 TFC membrane were elaborated. Metal-organic frameworks (MOFs) materials show great potential in wastewater separation applications. In this study, zirconium-based MOFs (UiO-66) were prepared and constructed universal, high-performance, and flexible nanofiltration (NF) membrane for various dyes and antibiotics separation. The substrate was constructed by two-steps, a) doping graphene oxide (GO) sheets into the membrane casting solution containing polyacrylonitrile (PAN) and forming 2D-3D connecting pores by phase immersion conversion method (defined as GO@PAN), b) immersing the GO@PAN substrate into dopamine solution to self-polymerize into chain macromolecules, which obtaining good compatible and flexible substrate (defined as PGP). Moreover, the UiO-66 was synthesized via solvothermal method and subsequently coated onto the PGP substrate by vacuum-assisted filtration. Benefiting from the water stability, porous structure, and negative charge of UiO-66, the outstanding filtration performance of the UiO-66/PGP thin-film composite (TFC) membrane was achieved. The pure water permeability of the UiO-66/PGP TFC membrane was 31.33 ± 0.75 L m−2h−1 bar−1, and the rejection rates for dye (Congo red, Methyl orange, Rhodamine B, and Methylene blue) and antibiotic (Tetracycline hydrochloride, Oxytetracycline, and Ciprofloxacin) were above 94%. Therefore, we further explored the retention mechanism of the UiO-66/PGP TFC membrane for dye and antibiotic separation (size exclusion and electrostatic interaction). More importantly, antifouling properties and long-time stability of the UiO-66/PGP TFC membrane were also evaluated. These results indicated that the prepared UiO-66/PGP TFC membrane is promising for wastewater treatment, separation, and purification in many industrial and pharmaceutical fields. [ABSTRACT FROM AUTHOR]

In this work, a "signal-off" sandwich electrochemiluminescence (ECL) immunosensor was fabricated for ingenious detection of Alzheimer's disease marker β-amyloid (Aβ) based on dual metal-organic frameworks (dual-MOFs), which included NH 2 -UiO-66 and MIL-101. Dual-MOFs with high porosity and plentiful functional groups can increase the biomolecules binding rate, and through the synergy with the different materials can effectively amplify the inherent properties of the material itself. Ru(bpy) 3 2+ was capsulated in NH 2 -UiO-66 as luminophor, the complex possessed steady and excellent luminescence efficiency as well as large specific surface area to load sufficient antibodies. MoS 2 quantum dots (MoS 2 QDs) combined with MIL-101 via Au–S bond. MIL-101@Au–MoS 2 QDs was used for the label of secondary antibodies (Ab 2) to quench the ECL signal of Ru(bpy) 3 2+/NH 2 -UiO-66. The amount of Ab 2 -MIL-101@Au–MoS 2 QDs bound to antigen will gradually accrue with the increase of the concentration of Aβ, which led to "signal-off" for accurate estimation of Aβ. Under optimal conditions, the developed assay for Aβ detection demonstrated a wide linear range of 10−5 ng mL−1 to 50 ng mL−1 and the detection limit was as low as 3.32 fg mL−1 (S/N = 3). The cooperation of dual-MOFs has potential as a universal strategy for quantitative analysis of other targets. Ru(bpy) 3 2+ and MoS 2 QDs simultaneously reacted with tripropylamine (TPA) to consume the co-reactant in the PBS solution, resulting in "Signal off". Image 1 • Dual-MOFs were applied to ECL signal amplification and annihilation. • A "signal-off" method for detecting Aβ was developed. • Ru(bpy) 3 2+/NH 2 -UiO-66 existed excellent ECL signal. • The quenching mechanism of MoS 2 to Ru(bpy) 3 2+ was firstly proposed. [ABSTRACT FROM AUTHOR]