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A novel acyl chloride-mediated strategy is used to synthesize rhodanine-modified UiO-66 adsorbent. Benefitting from the high grafting density of rhodanine, the optimal UiO-66-NH 2 @20Rd exhibits ultra-high adsorption capacity and selectivity for Ag(I) recovery. This study highlights that such a general strategy can provide a valuable avenue toward various functional adsorption materials. [Display omitted] Silver (Ag) recovery is essential for ecological protection, human health and economic benefits. Effective capture of Ag(I) from wastewater is still challenging due to insufficient accessible sites of adsorbents. Herein, an acyl chloride-mediated strategy is developed to synthesize rhodanine (Rd) modified UiO-66 derivatives for Ag(I) adsorption. Benefitting from the high grafting density of Rd, the optimal Rd-modified UiO-66-NH 2 (UiO-66-NH 2 @20Rd) features an ultra-high uptake capacity (maximum capacity of 923.9 mg·g−1) and selectivity (maximum selectivity coefficient of 1665.52) for Ag(I). Almost 90 % of Ag(I) could be captured in one minute over UiO-66-NH 2 @20Rd and maintained a removal rate of 98.9 % even after six cycles. Moreover, a fixed-bed column test demonstrates that approximately 21,780 bed volumes of Ag(I) simulated wastewater can be effectively treated, indicating great promise for practical application. Mechanism investigation illustrates that outstanding performance can be attributed to the synergistic effect of Ag(I) adsorption and reduction on dense rhodanine sites. This study highlights that such a general strategy can provide a valuable avenue toward various functional adsorption materials. [ABSTRACT FROM AUTHOR]

The pyrazine-based Fe-MOFs with modulated O-Fe-N coordination were developed by ligand substitution strategy, which exhibited enhanced catalytic hydroxyl radical (OH) generation in Fenton-like process via degreasing H 2 O 2 activation barrier and triggering OH involved Fe(III) reduction. [Display omitted] Rational design of coordination environment of Fe-based metal-organic frameworks (Fe-MOFs) is still a challenge in achieving enhanced catalytic activity for Fenten-like advanced oxidation process. Here in, novel porous Fe-MOFs with modulated O-Fe-N coordination was developed by configurating amino terephthalic acid (H 2 ATA) and pyrazine-dicarboxylic acid (PzDC) (Fe-ATA/PzDC-7:3). PzDC ligands introduce pyridine-N sites to form O-Fe-N coordination with lower binding energy, which affect the local electronic environment of Fe-clusters in Fe-ATA, thus decreased its interfacial H 2 O 2 activation barrier. O-Fe-N coordination also accelerate Fe(II)/Fe(III) cycling of Fe-clusters by triggering the reactive oxidant species mediated Fe(III) reduction. As such, Fe-ATA/PzDC-7:3/H 2 O 2 system exhibited excellent degradation performance for typical antibiotic sulfamethoxazole (SMX), in which the steady-state concentration of hydroxyl radical (OH) was 1.6 times higher than that of unregulated Fe-ATA. Overall, this study highlights the role of O-Fe-N coordination and the electronic environment of Fe-clusters on regulating Fenton-like catalytic performance, and provides a platform for precise engineering of Fe-MOFs. [ABSTRACT FROM AUTHOR]

[Display omitted] • A novel and simple scheme for loading aluminum hypophosphite on MOF derivatives. • The dual function of carboxymethyl cellulose: buffer and support layer. • The double-layer hollow nano hybrid is integrated with multiple flame retardant elements. • The flame retardancy of epoxy resin composites is significantly improved after the introduction of AHP/ACP@CMC due to its unique components and nanostructure. Aluminum hypophosphite (AHP) has been used as a flame retardant for a long time. Previous studies about AHP employed in flame retardant materials mostly focus on coating, modification, and complex system. It is valuable to explore simple experimental steps to prepare nano hybrids with AHP and metal–organic frameworks (MOFs). We found acidic substances could etch zeolitic imidazolate framework-67 (ZIF-67) to obtain MOF derivatives. Unfortunately, AHP and ZIF-67 could not directly form a hybrid. Therefore, carboxymethylcellulose (CMC) is introduced as a dual function layer (buffer and support). The CMC resists the complete conversion of ZIF-67 etched by phosphoric acid to amorphous cobalt phosphate hydrate (ACP). Meanwhile, CMC containing hydroxyl groups combines with AHP through electrostatic interaction and coordination bonds. A double-layer hollow MOF derivative is synthesized through this one-stone-two-birds strategy. Due to multiple flame retardant elements and unique nanostructure, this MOF derivative endows epoxy (EP) resin with excellent flame retardancy. With 2.0 wt% addition, the peak heat release rate (pHRR) and total heat release (THR) of EP/AHP/ACP@CMC are decreased by 47.8 and 21.0 %, respectively. This study proposes a novel scheme that converts AHP into MOF derivatives as high-performance FRs. [ABSTRACT FROM AUTHOR]

[Display omitted] The excessive CO 2 emission has gained global attentions due to its potential effects on climate change, plant nutrition deterioration, and human health and safety. Metal-organic frameworks (MOFs) featured with high specific surface area, adjustable pore size, and tailorable morphology have been widely applied for CO 2 capture. However, some drawbacks of poor mechanical stability and uneven distribution of mesopores limit their further applications. Herein, we demonstrate a one-step synthesis of bimetallic center framework (OSSBCF) and pore reconstruction (PRC) strategy to prepare the hierarchical porous Zn/Co-ZIF@ANF aerogels. This unique design achieves the construction of efficient gas transfer channels and creates massive micropores with abundant Lewis basic adsorption sites. Benefiting from theses merits, the bimetallic Zn/Co-ZIF@ANF aerogels demonstrate high MOFs loading mass of 47.51 wt%, high specific surface area of 686.39 m2g−1, and large porosity of 99.31 %. Moreover, the bimetallic Zn/Co-ZIF@ANF aerogels exhibit an enhanced CO 2 adsorption capacity of 5.99 mmol/g and CO 2 /N 2 adsorption selectivity of 35 at 25 °C and 1 bar. The CO 2 capacity of bimetallic Zn/Co-ZIF@ANF aerogels keep up to 95.19 % after ten cycles of CO 2 adsorption, indicating the excellent long-term recycle stability. Therefore, this study provides a promising strategy to engineer hierarchical porous bimetallic MOF aerogels toward practical CO 2 capture. [ABSTRACT FROM AUTHOR]

[Display omitted] • Pd/DUT-67-PZDC(10) catalyst with highly dispersed Pd NPs was prepared. • The hierarchically microporous structural property of the DUT-67-PZDC support is beneficial for the stabilization of Pd NPs. • The dual N sites on the DUT-67-PZDC(10) support could act as excellent proton buffers to stimulate the O-H bond cleavage in FA. • The ultrasmall size (1.7 nm) and high dispersion of Pd NPs could expose more catalytic active sites. • The Pd/DUT-67-PZDC(10) catalyst shows an initial TOF value of 2572h−1, 100 % FA conversion and H 2 selectivity, and excellent stability at 60 °C. The highly dispersed ultrasmall palladium nanoparticles (Pd NPs) (1.7 nm) were successfully immobilized on a N -containing metal–organic framework (MOF, DUT-67-PZDC) using a co-reduction method, and it is used as an excellent catalyst for formic acid dehydrogenation (FAD). The optimized catalyst Pd/DUT-67-PZDC(10, 10 wt% Pd loading) shows 100% hydrogen (H 2) selectivity and formic acid (FA) conversion at 60 °C, and the commendable initial turnover frequency (TOF) values of 2572 h−1 with the sodium formate (SF) as an additive and 1059 h−1 even without SF, which is better than most reported MOF supported Pd monometallic heterogeneous catalysts. The activation energy (Ea) of FAD is 43.2 KJ/mol, which is lower than most heterogeneous catalysts. In addition, the optimized catalyst Pd/DUT-67-PZDC(10) maintained good stability over five consecutive runs, demonstrating only minimal decline in catalytic activity. The outstanding catalytic performance could be ascribed to the synergistic corporations of the unique structure of DUT-67-PZDC carrier with hierarchical pore characteristic, the metal-support interaction (MSI) between the active Pd NPs and DUT-67-PZDC, the highly dispersed Pd NPs with ultrafine size serve as the catalytic active site, as well as the N sites on the support could act as the proton buffers. This work provides a new paradigm for the efficient H 2 production of FAD by constructing highly active heterogeneous Pd-based catalysts using MOF supports. [ABSTRACT FROM AUTHOR]

[Display omitted] • MnO X catalysts with tunable morphology and oxygen vacancy defects were prepared. • Tailoring the morphology of MnO X can greatly improve the catalytic activity. • The oxygen vacancy defect on MnO X can expedite the activation-oxidation of toluene. To clarify the key role of oxygen vacancy defects on enhancing the oxidative activity of the catalysts, metal–organic frameworks (MOFs) derived MnO X catalysts with different morphologies and oxygen vacancy defects were successfully prepared using a facile in-situ self-assembly strategy with different alkali moderators. The obtained morphologies included three-dimensional (3D) triangular cone stacked MnO X hollow sphere (MnO X -H) and 3D nanoparticle stacked MnO X nanosphere (MnO X -N). Compared to MnO X -N, MnO X -H exhibited higher activity for the oxidation of toluene (T 90 = 226 °C). This was mainly due to the large number of oxygen vacancy defects and Mn4+ species in the MnO X -H catalyst. In addition, the hollow structure of MnO X -H not only facilitated toluene adsorption and activation of toluene and also provided more active sites for toluene oxidation. Reaction mechanism studies showed that the conversion of toluene to benzoate could be realized over MnO X -H catalyst during toluene adsorption at room temperature. In addition, abundant oxygen vacancy defects can accelerate the activated oxidation of toluene and the formation of oxidation products during toluene oxidation. [ABSTRACT FROM AUTHOR]

[Display omitted] Phase behavior of nanoconfined fluids adsorbed in metal–organic frameworks is of paramount importance for the design of advanced materials for energy and gas storage, separations, electrochemical devices, sensors, and drug delivery, as well as for the pore structure characterization. Phase transformations in adsorbed fluids often involve long-lasting metastable states and hysteresis that has been well-documented in gas adsorption–desorption and nonwetting fluid intrusion-extrusion experiments. However, theoretical prediction of the observed nanophase behavior remains a challenging problem. The mesoscopic canonical, or mesocanonical, ensemble (MCE) is devised to study the nanophase behavior under conditions of controlled fluctuations to stabilize metastable and labile states. Here, we implement and apply the MCE Monte Carlo (MCEMC) simulation scheme to predict the origins of reversible and hysteric adsorption phase transitions in a series of practical MOF materials, including IRMOF-1, ZIF-412, UiO-66, Cu-BTC, IRMOF-74-V, VII, and IX. The MCEMC method, called the gauge cell method, allows to produce Van der Waals type isotherms with distinctive swings around the phase transition regions. The constructed isotherms determine the positions of phase equilibrium and spinodals, as well as the nucleation barriers separating metastable states. We demonstrate the unique capabilities of the MCEMC method in quantitative predictions of experimental observations compared with the conventional grand canonical and canonical ensemble simulations. The MCEMC method is implemented in the open-source RASPA and LAMMPS software packages and recommended for studies of adsorption behavior and pore structure characterization of MOFs and other nanoporous materials. [ABSTRACT FROM AUTHOR]

[Display omitted] Ti-based Metal–organic frameworks (Ti-MOF) have been extensively investigated for producing hydrogen via solar water splitting, while their intrinsic activities are still retarded by the poor performance of photocarriers separation and utilization. Herein, a donor-acceptor (D-A) supramolecular photocatalyst is successfully constructed via encapsulating fullerene (C 60) into MIL-125-NH 2 and meanwhile depositing individual Pt atoms as cocatalyst. The as-prepared C 60 @MIL-125-NH 2 -Pt exhibits remarkable activity in photocatalytic water splitting, with a H 2 formation rate of 1180 μmol g−1 h−1, which is ∼ 12 times higher than that of the pristine MIL-125-NH 2. Further investigations indicate that the host-guest interactions between C 60 and MIL-125-NH 2 strengthen the built-in electric field, which greatly facilitates the separation and migration of photogenerated charge carriers. In addition, the cocatalyst of individual Pt atoms not only further promotes the separation and transport of carriers but also enhances the contact between water and the catalyst. All of these factors directly contribute to the superior activity of C 60 @MIL-125-NH 2 -Pt. This work provides a new perspective for constructing D-A supramolecular photocatalysts for enhanced charge separation and making full use of photoelectrons to realize efficient hydrogen production. [ABSTRACT FROM AUTHOR]

[Display omitted] Hydrogen peroxide (H 2 O 2) emerges as a viable oxidant for fuel cells, necessitating the development of an efficient and cost-effective electrocatalyst for the hydrogen peroxide reduction reaction (HPRR). In this study, we synthesized a self-supporting, highly active HPRR electrocatalyst comprising two morphologically distinct components: CeO 2 -NiCo 2 O 4 nanowires and CeO 2 -NiCo 2 O 4 metal organic framework derivatives, via a two-step hydrothermal process followed by air calcination. X-ray diffraction and transmission electron microscopy analysis confirmed the presence of CeO 2 and NiCo 2 O 4 , revealing the amalgamated interface between them. CeO 2 exhibits multifunctionality in regulating the surface electronic configuration of NiCo 2 O 4 , fostering synergistic connections, and introducing oxygen deficiencies to enhance the catalytic efficacy in HPRR. Electrochemical measurements demonstrate a reduction current density of 789.9 mA·cm−2 at −0.8 V vs. Ag/AgCl. The assembly of direct borohydride-hydrogen peroxide fuel cell (DBHPFC) exhibits a peak power density of 45.2 mW·cm−2, demonstrating durable stability over a continuous operation period of 120 h. This investigation providing evidence that the fabrication of heterostructured catalysts based on CeO 2 for HPRR is a viable approach for the development of high-efficiency electrocatalysts in fuel cell technology. [ABSTRACT FROM AUTHOR]

Schematic illustration showing the process of creating conductive MOF-coated 3D-printed scaffolds and their use in the treatment of osteosarcoma and for aiding in bone repair. [Display omitted] The integration of functional nanomaterials with tissue engineering scaffolds has emerged as a promising solution for simultaneously treating malignant bone tumors and repairing resected bone defects. However, achieving a uniform bioactive interface on 3D-printing polymer scaffolds with minimized microstructural heterogeneity remains a challenge. In this study, we report a facile metal-coordination self-assembly strategy for the surface engineering of 3D-printed polycaprolactone (PCL) scaffolds with nanostructured two-dimensional conjugated metal–organic frameworks (cMOFs) consisting of Cu ions and 2,3,6,7,10,11-hexahydroxytriphenylene (HHTP). A tunable thickness of Cu-HHTP cMOF on PCL scaffolds was achieved via the alternative deposition of metal ions and HHTP. The resulting composite PCL@Cu-HHTP scaffolds not only demonstrated potent photothermal conversion capability for efficient OS ablation but also promoted the bone repair process by virtue of their cell-friendly hydrophilic interfaces. Therefore, the cMOF-engineered dual-functional 3D-printing scaffolds show promising potential for treating bone tumors by offering sequential anti-tumor effects and bone regeneration capabilities. This work also presents a new avenue for the interface engineering of bioactive scaffolds to meet multifaceted demands in osteosarcoma-related bone defects. [ABSTRACT FROM AUTHOR]

CoP and N, O, P triple-doped carbon composites were prepared by low-temperature tandem reaction using MOF as a self-sacrificial template, and their lithium storage properties and mechanisms were investigated. [Display omitted] • The formation of dispersed cubic structure facilitates electrolyte penetration and Li+ diffusion. • Heteroatoms doping adjusts the local electric field of the anode improving the reactivity of the material. • Transformation of the mechanism of CoP anode before and after cycling was confirmed by ex-situ techniques. • Theoretical calculations demonstrate the synergistic effect between the co-doped carbon layer and CoP. Cobalt phosphide (CoP) with high theoretical capacity as well as ceramic-like and metal-like properties is considered as a promising anode for lithium-ion batteries (LIBs). However, the large volume change and sluggish kinetic response limit its practical application. The optimization of composition, structural control and performance regulation of CoP electrodes can be achieved by the bottom-up assembly technique of metal–organic frameworks (MOFs). Due to the effective electronic regulation and lithiophilicity brought by the multiple heteroatoms doping and the synergistic effect of the unique structure derived from MOFs, the N, O, P triple-doped carbon and CoP composites (ZCP@NOP) exhibited excellent rate capability (554.61 mAh g−1 at 2 A g−1) and cycling stability (806.7 mAh g−1 after 500 cycles at 0.5 A g−1). The essence and evolution of lithium storage mechanism in CoP electrodes are also confirmed by the ex-situ techniques. The synergistic benefits of heteroatom co-doping carbon and cobalt phosphide, such as the decrease of the diffusion energy barrier of Li-ions and the optimization of electronic structures, are highlighted in theoretical calculations. In conclusion, new thoughts and ideas for the creation of future battery anode are provided by the combination of the N, O, P co-doping and the adaptable structural adjustment technique. [ABSTRACT FROM AUTHOR]

A facile preparation protocol for a porous carbon skeleton supported lithium iron phosphate nanocomposite material (LFP/C) is derived from a ferric gallate (Fe-GA) metal–organic framework (MOF) precursor. [Display omitted] Lithium iron phosphate (LiFePO 4 , LFP) has become one of the most widely used cathode materials for lithium-ion batteries. The inferior lithium-ion diffusion rate of LFP crystals always incurs poor rate capability and unsatisfactory low-temperature performances. To meet with the requirements from the ever-growing market, it is of great significance to synthesize carbon supported LFP nanocomposite (LFP/C) cathode materials using cost effective and environmentally friendly methods. In this work, an LFP/C cathode material is straightforwardly prepared from a metal–organic framework (MOF) precursor ferric gallate (Fe-GA) using its self-template effect. The Fe-GA precursor is firstly fabricated from the redox coprecipitation reaction between Fe foils and gallic acid (GA) molecules in mild aqueous phase. Then the Fe-GA is directly converted to the LFP/C sample after a following solid-state reaction. In half-cells, the LFP/C composite exhibits a reversible capacity of 109.7 mAh·g−1 after 500 cycles under the current rate of 100 mA·g−1 at 25 °C as well as good rate capabilities. In the LFP/C//graphite full-cells, the LFP/C composite can deliver a reversible capacity of 71.4 mAh·g−1 after 50 cycles in the same condition as the half-cells. The electrochemical performances of the LFP/C cathode in half-cells at lower temperature of −10 °C are also examined. Particularly, the evolution of samples has been explored and the lithium-ion storage mechanism of the LFP/C cathode has been unveiled. The sample synthesis protocol is straightforward, eco-friendly and atomic efficient, which can be considered to have good potential for scaling-up. [ABSTRACT FROM AUTHOR]

A new concept of biomimetic lubricating nanosystem that realizes long-time lubrication, photothermal responsiveness and anti-inflammation property is developed. High drug loading ratio of 99%, great friction reduction by 75% for more than 7200 times without failure, and effective up-regulation of cartilage anabolic genes and down-regulation of catabolic proteases and pain-related genes are achieved. Our work provides a bioinspired strategy to employ metal organic framework with controlled surface and structure for synergistic therapy of osteoarthritis. [Display omitted] Failure of articular cartilage lubrication and inflammation are the main causes of osteoarthritis (OA), and integrated treatment realizing joint lubrication and anti-inflammation is becoming the most effective treat model. Inspired by low friction of human synovial fluid and adhesive chemical effect of mussels, our work reports a biomimetic lubricating system that realizes long-time lubrication, photothermal responsiveness and anti-inflammation property. To build the system, a dopamine-mediated strategy is developed to controllably graft hyaluronic acid on the surface of metal organic framework. The design constructs a biomimetic core–shell structure that has good dispersity and stability in water with a high drug loading ratio of 99%. Temperature of the solution rapidly increases to 55 °C under near-infrared light, and the hard-soft lubricating system well adheres to wear surfaces, and greatly reduces frictional coefficient by 75% for more than 7200 times without failure. Cell experiments show that the nanosystem enters cells by endocytosis, and releases medication in a sustained manner. The anti-inflammatory outcomes validate that the nanosystem prevents the progression of OA by down-regulating catabolic proteases and pain-related genes and up-regulating genes that are anabolic in cartilage. The study provides a bioinspired strategy to employ metal organic framework with controlled surface and structure for friction reduction and anti-inflammation, and develops a new concept of OA synergistic therapy model for practical applications. [ABSTRACT FROM AUTHOR]

[Display omitted] Improving ligand-to-active metal charge transfer (LAMCT) by finely tuning the organic ligand is a decisive strategy to enhance charge transfer in metal organic frameworks (MOFs)-based catalysts. However, in most MOFs loaded with active metal catalysts, electron transmission encounters massive obstacle at the interface between the two constituents owing to poor LAMCT. Herein, amines (–NH 2) functionalized MOFs (NH 2 -MIL-101(Cr)) encapsulated active metal Pt nanoclusters (NCs) catalysts are synthesized by the polyol reduction method and utilized for the photoreduction of CO 2. Surprisingly, the introduction of –NH 2 (electron donating) groups within the matrix of MIL-101(Cr) improved the electron migration through the LAMCT process, fostering a synergistic interaction with Pt. The combined experimental analysis exposed the high number of metallic Pt (Pt0) in Pt@NH 2 -MIL-101(Cr) catalyst through seamless electron shuttling from N of –NH 2 group to excited Pt generating versatile hybrid Pt-N catalytic centres. Consequently, these versatile hybrid catalytic centres act as electro-nucleophilic centres, which enable the efficient and selective conversion of C O bond in CO 2 to harvest CH 4 (131.0 µmol.g−1) and maintain excellent stability and selectivity for consecutive five rounds, superior to Pt@MIL-101(Cr) and most reported catalysts. Our study verified that the precise tuning of organic ligands in MOFs immensely improves the surface-active centres, electron migration, and catalytic selectivity of the excited Pt NCs catalysts encaged inside MOFs through an improved LAMCT pathway. [ABSTRACT FROM AUTHOR]

[Display omitted] • Inverted modulator synthesis of a novel cheap double-ligand Zr-based MOF (MA-MOF). • MA-MOF shows enhanced adsorption and photocatalytic degradation toward tetracycline. • MA-MOF yields holes, ·OH and ·O2− under visible-light for degrading tetracycline. Developing visible-light response photocatalysts with high activity and adsorption alongside sustainability is vitally important to environmental restoration. Here, we fabricated a novel metal organic framework (MOF) with cost-effective double-ligands (fumaric acid and 2-aminoterephthalic acid as ligand precursors, denoted as MA-MOF) via a facile solvothermal method. Specifically, crystalline [Zr 6 O 4 (OH) 4 (fumarate) 6 ] (MOF-801) can be only formed with monocarboxylic acids as modulators. Therefore, in the construction of crystalline double-ligand MA-MOF, the absence of monocarboxylic acid modulators successfully prevents the formation of crystalline MOF-801. Instead, the crystalline double-ligand MA-MOF is formed. Properties of MA-MOFs including the surface area, porosity, charge transfer resistance, and energy level position can be adjusted via altering the ratio of ligands. The optimal sample, MA-MOF2 (prepared with a molar ratio of fumaric acid and 2-aminoterephthalic acid being 2:1), shows a total 94.6% removal of tetracycline via adsorption and photodegradation, far exceeding the corresponding single-ligand counterparts. This work proposes an innovative inverted modulator strategy for constructing double-ligand MOFs. [ABSTRACT FROM AUTHOR]

A portable sensing platform with excellent performance was constructed using CoNi-MOF-based chitosan-polyacrylamide hydrogel as a signal amplifier for the detection of adrenaline. [Display omitted] The development of a portable smartphone-based electrochemical sensor for analyzing adrenaline levels in real samples can make a great contribution to the research community worldwide. In order to achieve this goal, the key challenge is to build sensing interfaces with excellent electrocatalytic properties. In this work, microspherical bimetallic metal–organic frameworks (CoNi-MOF) consisting of nanoclusters were first synthesized using a hydrothermal method. On this basis, the catalytic activity of pure chitosan-polyacrylamide hydrogel (CS-PAM) was modulated by adding different amounts of CoNi-MOF during the in-situ synthesis of CS-PAM. Finally, a portable electrochemical detection system based on CS-PAM was established for the detection of adrenaline. A series of resulting composite hydrogels with a large specific surface area, abundant active sites, and unique network structure facilitate the enrichment and catalysis of adrenaline molecules. Under optimal conditions, the analytical platform constructed by using CoNi-MOF-based CS-PAM has the advantages of a wide detection range (0.5–10 and 10–2500 μM), a low detection limit (0.167 μM), and high sensitivity (0.182 and 0.133 μA·μM·cm−2). In addition, the sensor maintains selective detection of the target in the presence of many different types of interferences, and the current response is not significantly reduced even after 60 cycles of testing. We strongly believe that the designed smart portable sensing can realize the accurate determination of adrenaline in complex systems, and this study can provide new ideas for the research of MOFs-based hydrogels in electrochemical analysis. [ABSTRACT FROM AUTHOR]

[Display omitted] • Prepared ZIF-67/CoFe-LDH has excellent catalytic performance. • DFT demonstrated that oxygen vacancies mediated free radical and non-free radical pathways. • The role of reactive oxygen species in ZIF-67/CoFe-LDH/PMS system was studied. • The SMX degradation pathway was analyzed and the biotoxicity of the degradation intermediates was estimated. Herein, a novel rich oxygen vacancy (Ov) cobalt-iron hydrotalcite composite cobalt metal–organic framework material (ZIF-67/CoFe-LDH) was prepared by simple urea water and heat reduction approach and utilized for the peroxymonosulfate (PMS) system to remove sulfamethoxazole (SMX). 95 ± 1.32 % SMX (20 mg/L) was able to degraded in 20 min with TOC removal of 53 ± 1.56 % in ZIF-67/CoFe-LDH/PMS system. The system maintained a fantastic catalytic capability with wide pH range (3–9) and common interfering substances (Cl−, NO 3 −, CO 3 2−, PO 4 2− and humic acid (HA)), and the degradation efficiency could even remain 80.2 ± 1.48 % at the fifth cycle. Meanwhile, the applicability and feasibility of the catalysts for practical water treatment was verified by the degradation effects of SMX in different water environments and several other typical pollutants. Co and Fe bimetallic active centers synergistically activate PMS, and density functional theory (DFT) predicted adsorption energy about Ov in ZIF-67/CoFe-LDH for PMS was 1.335 eV, and O O bond length of PMS was stretched to 1.826 Å. As a result, PMS was more easily activated and broken, which accelerated the singlet oxygen (1O 2), sulfate radical (SO 4 •−), high-valent metals and other reactive oxygen species (ROS). Radical and non-radical jointly degrading the pollutants improved the catalytic effect. Finally, SMX degradation intermediates were analyzed to explain the degradation pathway and their biotoxicity was also evaluated. This paper provides a new research perspective of oxygen vacancy activating PMS to degrade pollutants. [ABSTRACT FROM AUTHOR]

An efficient ligand-induced MOF-on-MOF strategy is proposed to fabricate hollow ZIF-67@PBA heterostructures. By manipulating the Co2+/Zn2+ ratio in the precursor ZIF-67, the catalyst Co x Fe-ZP can be conveniently obtained after pyrolysis, showing satisfactory electrocatalytic oxygen evolution. [Display omitted] There is significant anticipation for high-efficiency and cost-effective non-precious metal-based catalysts to advance the industrial application of the anodic oxygen evolution reaction (OER) for hydrogen production. This study introduces an efficient strategy that utilizes ligand-induced metal–organic framework (MOF) building blocks for the synthesis of hollow binary zeolitic imidazolate frameworks 67 (ZIF-67) and Prussian blue analogues (PBAs) (ZIF-67@PBA) heterostructures through a hybrid MOF-on-MOF approach. Manipulating the Co2+/Zn2+ ratio in the precursor ZIF-67 allows for the convenient synthesis of the final product, denoted as Co x Fe-ZP, after pyrolysis, where the inclusion of Zn effectively modulates the distribution of Co in the catalyst. The resulting Co x Fe-ZP catalysts exhibit a positive synergistic effect between hollow graphitic carbon nanomaterials and Fe-doped Co nanoparticles. The optimal Co 0.3 Fe-ZP catalyst demonstrates satisfactory OER performance, achieving an overpotential of 302 mV at 10 mA cm−2 and a small Tafel slope of 60.0 mV dec−1. Further analysis of the activation energy confirms that the enhanced OER activity of Co 0.3 Fe-ZP can be reasonably attributed to the combined influence of its morphology and composition. This study demonstrates a ligand-induced method for examining the morphology and electrochemical properties of grown binary MOF-on-MOF heterostructures for OER applications. [ABSTRACT FROM AUTHOR]

[Display omitted] • Plastics waster derived defective d -UiO-66 was synthesized by solvent-free routine. • d -UiO-66 possesses higher surface areas and pore volume than pristine UiO-66. • The LOM adsorption capacity of d -UiO-66 is 3.5 times of UiO-66. • d -UiO-66 exhibits the record LOM adsorption capacity of 588 g mg−1. • Defects in d -UiO-66 promote the mass transfer and create more active sites. Large amount of polyethylene terephthalate (PET) plastics waster and emerging contaminants in water, including fluoroquinolone antibiotics, pose challenges to human survival. In this work, a green synthesis scheme is proposed in which the defective UiO-66 (d -UiO-66) is fabricated via a solvent-free routine by using PET plastics waster as raw materials for lomefloxacin (LOM) removal. In comparison with defect-free UiO-66, the created defect imparts d -UiO-66 with higher porosity and abundant defective Zr sites, which are beneficial to boost LOM adsorption. As expected, d -UiO-66 exhibited excellent LOM adsorption performances, showcasing a saturation adsorption capacity of 588 mg g−1 and a kinetic rate constant of 0.204 g mg−1 h−1, which are 3.5 and 2.0 times higher than those of the pristine UiO-66, respectively. Remarkably, the LOM saturation adsorption capacity of d -UiO-66 surpasses that of all reported adsorbents. Mechanism study reveals that this outstanding adsorption performance of d -UiO-66 is mainly ascribed to the abundant defective sites, high porosity, together with the strong hydrogen bonding interaction and π-π stacking interaction between d -UiO-66 and LOM. Therefore, the d -UiO-66 obtained by the solvent-free method can not only effectively upcycle PET plastic waster, but also efficiently remove LOM, demonstrating a potential routine to simultaneous address the solid PET waster and wastewater. [ABSTRACT FROM AUTHOR]

[Display omitted] In this study, a directional loading of cadmium sulfide (CdS) nanoparticles (NPs) was achieved on the opposite edges of nickel metal–organic framework (Ni-MOF) nanosheets (NSs) by adjusting the weight ratio of CdS NPs in the reaction process to produce effective visible light photocatalysts. The close contact between the zero-dimensional (0D) and two-dimensional (2D) regions and the matching positions of the bands promoted charge separation and heterojunction formation. The optimal CdS NPs loading of composite material was 40 wt%. At this ratio, CdS NPs grew primarily at the opposite edges of the Ni-MOF NSs rather than on their surfaces. When lactic acid was used as the sacrificial agent, the hydrogen production rate of the 40 %-CdS/Ni-MOF heterojunction under visible light irradiation was 19.6 mmol h−1 g−1, making a 20-fold enhancement compared to the original CdS NPs sample (1.0 mmol h−1 g−1). The charge carriers generated in CdS NPs were transferred to Ni-MOF NSs through heterojunctions, where Ni-MOF NSs also served as cocatalysts to improve hydrogen production. The combination of the two materials improved the light absorption ability. In particular, the 40 %-CdS/Ni-MOF heterojunction exhibited good photostability, effectively preventing the photocorrosion of CdS NPs. This study introduces an approach for constructing efficient and stable photocatalysts for visible light–driven photocatalytic hydrogen production. [ABSTRACT FROM AUTHOR]

Constructing a hierarchically porous MOF@COF (HP MOF@COF) structure for enhancing the gas-adsorption kinetics. [Display omitted] For ethylene purification, C 2 H 6 -selective metal–organic frameworks (MOFs) show great potential to directly produce polymer-grade C 2 H 4 from C 2 H 6 /C 2 H 4 mixtures. Most C 2 H 6 -traping MOFs are ultra-microporous structures so as to strengthen multiple supramolecular interactions with C 2 H 6. However, the narrowed pore channels of C 2 H 6 -traping MOFs cause large guest diffusion barriers, greatly hampering their practical applications. Herein, we present a feasible strategy by precisely constructing hierarchically porous MOF@COF core–shell structures to address this issue. Additional mesoporous diffusion channels were incorporated between MOF crystals through the construction of the COF shell, thereby enhancing the gas adsorption kinetics. Notably, designing a core–shell MOF@COF structure with an optimal coating amount of mesoporous COF shell will further improve the gas diffusion rate. Breakthrough experiments reveal that the tailored MOF@COF composites can effectively achieve C 2 H 6 /C 2 H 4 separation and maintain its separation performance over five continuous measurement cycles. This investigation opens up a new avenue to solve the diffusion/transfer issues and provides more opportunities and potentials for MOF@COF composites in practical separation applications. [ABSTRACT FROM AUTHOR]

[Display omitted] Metal-organic frameworks (MOFs) are highly suitable precursors for supercapacitor electrode materials owing to their high porosity and stable backbone structures that offer several advantages for redox reactions and rapid ion transport. In this study, a carbon-coated Ni 9 S 8 composite (Ni 9 S 8 @C-5) was prepared via sulfuration at 500 ℃ using a spherical Ni-MOF as the sacrificial template. The stable carbon skeleton derived from Ni-MOF and positive structure–activity relationship due to the multinuclear Ni 9 S 8 components resulted in a specific capacity of 278.06 mAh·g−1 at 1 A·g−1. Additionally, the hybrid supercapacitor (HSC) constructed using Ni 9 S 8 @C-5 as the positive electrode and the laboratory-prepared coal pitch-based activated carbon (CTP-AC) as the negative electrode achieved an energy density of 69.32 Wh·kg−1 at a power density of 800.06 W·kg−1, and capacity retention of 83.06 % after 5000 cycles of charging and discharging at 5 A·g−1. The Ni-MOF sacrificial template method proposed in this study effectively addresses the challenges associated with structural collapse and agglomeration of Ni 9 S 8 during electrochemical reactions, thus improving its electrochemical performance. Hence, a simple preparation method is demonstrated, with broad application prospects in supercapacitor electrodes. [ABSTRACT FROM AUTHOR]

[Display omitted] • Series of thermo-responsive microgels hybrids with tunable LCST were synthesized by varying feeding mass ratio of monomers. • Effective dose-effect relationships of copolymer microgels hybrids were constructed for enhancing the aqueous lubrication. • Dual function of thermo-responsive aqueous lubrication and s ustained drug release were achieved for synergetic OA treatment. Developing stimulus-responsive properties of drug delivery nanocarriers combined with enhanced joint lubrication is an effective synergistic strategy for treating osteoarthritis. Poly(N -isopropylacrylamide) (PNIPAm) is a typical thermo-responsive polymer, which can achieve drug delivery by transition from swollen state to collapsed state. However, undesired transition temperature, limited drug loading capacity, and weakened mechanical properties in joint present obstacles to use as drug delivery nanocarriers. In this work, we demonstrate dose–effect relationship between the PNIPAm-based copolymer and nanoscale metal–organic frameworks on enhancing both aqueous lubrication and drug delivery performance of a hybrid osteoarthritis (OA) nanocarrier. A series of NIPAm and poly(ethylene glycol)methacrylate (PEGMa) copolymer microgels with different feeding content are optimized to grow on the surface of MIL-101(Cr) nanoparticles via one-pot soap-free emulsion copolymerization method. By changing the feeding mass ratio of NIPAm and PEGMa, MIL-101(Cr)@P(NIPAm-g-PEGMa x) (x = 0, 1, 2, 3, and 4, named MPNP x) hybrids can ameliorate the lower critical solution temperature to match with OA and enhance the aqueous lubrication performance. Among the as-synthesized hybrids, MPNP 3 hybrids manifested the notable enhanced thermo-responsive tribological performance due to the synergistic effect of "hydration lubrication" and "ball-bearing" function of the optimized copolymer microgel layer on the surface of metal–organic frameworks (MOFs). Anti-inflammatory drug loading is enabled by the high surface area and porosity of the MOFs, and the MPNP 3 drug delivery nanocarriers achieve thermo-responsive release in vitro. Our work establishes the dose–effect relationship between thermo-responsive NIPAm and hydrophilic PEGMa of the copolymer grown on the surface of MOFs, providing valuable insights for improving the versatility of stimuli-responsive for biomedical application. [ABSTRACT FROM AUTHOR]

[Display omitted] Sonodynamic therapy (SDT) is a minimally invasive therapeutic approach that utilizes sonosensitizers to catalyze substrates and generate reactive oxygen species (ROS) under ultrasound stimulation, ultimately inducing tumor cell death. Enhancing the piezoelectric properties of nanomaterials and modulating the semiconductor energy band are effective strategies to improve the catalytic efficiency of sonosensitizers. In this study, we developed a two-dimensional (2D) copper-based piezoelectric metal–organic framework (MOF) sonosensitizer, denoted as CM, through the coordination of copper and dimethylimidazole. The unique 2D MOF structure imparts CM with piezoelectric characteristics, enabling it to enhance SDT efficacy by modulating the semiconductor bandgap and carrier mobility. Upon ultrasound irradiation, CM catalyzes oxygen to undergo a cascade reaction, producing highly toxic singlet oxygen. Additionally, cupric ions in CM can be reduced by glutathione, facilitating the spontaneous catalysis of hydrogen peroxide in tumors to generate hydroxyl radicals and deplete glutathione, thereby inducing oxidative damage. Moreover, cupric ions in CM can trigger tumor cell cuproptosis, which, in combination with the generated ROS, accelerates cell death. Thus, this study establishes a MOF-based system for controllably inducing multi-pathway cancer cell death and provides a foundation for enhancing ultrasound-catalyzed tumor therapy through the optimization of piezoelectric properties. [ABSTRACT FROM AUTHOR]

[Display omitted] • A novel N,S co-doped carbon encapsulated Co 2 P anchored on MXene was fabricated. • The MZPC-9 catalyst exhibited excellent BPA removal (TOF/PMS = 291 L2 min−1 g−2). • The electron transfer-process (ETP) was the dominated reactive pathway. • The ETP-induced polymerization pathway of BPA was elucidated. The non-radical pathway dominated by the electron transfer process (ETP) has gained considerable attention for the removal of organic contaminants in persulfate-based advanced oxidation processes. Rationally designing new catalysts with optimized composition and structural merits and further elucidating the enhanced removal mechanism are of great importance. In this work, we successfully synthesized a nitrogen-sulfur co-doped carbon encapsulated cobalt phosphide (Co 2 P) on both sides of MXene nanosheets (MZPC) to degrade bisphenol A (BPA) from organic wastewater. The results indicated that BPA was degraded by 98.2 % in a mere 5 min using 0.1 g L-1 of peroxymonosulfate (PMS) and 0.05 g L-1 of the optimized catalyst (MZPC-9), exhibiting an excellent pseudo-first-order kinetics rate constant (k = 1.485 min−1). Uniformly dispersed Co 2 P nanoparticles (approximately 9.4 nm, calculated using the Scherrer equation) on both sides of MXene exhibited enhanced binding affinity with PMS, forming the MZPC-9-PMS* metastable complexes with potent oxidative capability. The resultant MZPC-9-PMS* complexes induced the polymerization reaction of BPA and achieved 81 % total organic carbon (TOC) removal. This study offers a novel perspective on the design of metal active centers to enhance the ETP-dominated non-radical pathway for pollutant degradation. [ABSTRACT FROM AUTHOR]

[Display omitted] Sonodynamic therapy is a promising, noninvasive, and precise tumor treatment that leverages sonosensitizers to generate cytotoxic reactive oxygen species during ultrasound stimulation. Gallic acid (GA), a natural polyphenol, possesses certain anti-tumor properties, but exhibits significant toxicity toward normal cells, limiting its application in cancer treatment. To overcome this issue, we synthesized a bismuth-gallic acid (BGA), coordinated metal–organic framework (MOF) nano-prodrug. Upon encountering glutathione (GSH), BGA gradually dissociated and depleted GSH, releasing GA, which had anti-tumor effects. As an MOF with semiconductor properties, BGA primarily produced superoxide anion radical upon ultrasound excitation. After the release of GA, GA generated superoxide anion radical and further produced high toxic singlet oxygen under ultrasound stimulation, while further oxidizing and consuming GSH, enhancing sonocatalytic performance. Additionally, the released GA induced cell cycle arrest, ultimately leading to apoptosis. Our results revealed that BGA, as a GSH-activated, metal-polyphenol MOF nano-prodrug, showed potential for use in breast tumor sonodynamic therapy, providing a novel strategy for precise tumor treatment. [ABSTRACT FROM AUTHOR]

The present work exhibits an efficient strategy to adjust the electron structure of Bi/Bi 2 O 3 -In 2 O 3 @C by the synergistic effects of Bi-In hetero-diatoms and nanoheterostructure. Also, the formed hetero-bridging absorption of *OCHO and d-d orbital coupling effect could regulate the d-band center and improve the DOS around E f , moderating the free energy of intermediates. Thus, the enhance ECO 2 RR performance can be observed. [Display omitted] Electrocatalytic CO 2 reduction reaction (ECO 2 RR) to value-added chemicals is of significant importance to control CO 2 emission and reach carbon neutrality. Herein, Bi/Bi 2 O 3 -In 2 O 3 @C electrocatalyst with nanosheet arrays is successfully fabricated by a facile solvothermal with subsequent calcination process. It is found that the electron structure of Bi/Bi 2 O 3 -In 2 O 3 @C can be adjusted by the synergistic effects of Bi-In hetero-diatoms, which can significantly enhance its inherent catalytic activity. As expected, it requires a maximum HCOOH faradaic efficiency (FE HCOOH) of 97.6 % at −1.1 V vs. Reversible Hydrogen Electrode (RHE), which further delivers over 90 % at a wide potential range of −0.8 to −1.4 V vs. RHE, and exhibits high stability of 90.1 % over 60-h long-term test. In-situ Raman analysis is performed to explore the mechanism of its excellent stability. Meanwhile, in-situ attenuated total reflection-Fourier-transform infrared (ATR-FTIR) analysis combined with theoretical calculations reveal that the hetero-bridging absorption of *OCHO and d-d orbital coupling effect can regulate d-band center of Bi/Bi 2 O 3 -In 2 O 3 @C and improve its density of states around E f , moderating free energy of intermediates, thereby the improved formate production performance can be seen. [ABSTRACT FROM AUTHOR]

A novel copper-based conductive metal organic framework with the dual ligands of pyromellitic dianhydride and 2-methylbenzimidazole (Cu-PD-2-MBI) effectively converted carbon dioxide to methane. [Display omitted] The development of a new system for the electrochemical carbon dioxide reduction reaction (ECO 2 RR) to methane (CH 4) is challenging, and novel conductive metal organic frameworks (c-MOFs) for efficient ECO 2 RR to CH 4 are critical to this system. Here, we report a novel c-MOF, copper-pyromellitic dianhydride-2-methylbenzimidazole (Cu-PD-2-MBI), in which the introduction of electron-withdrawing 2-methylbenzimidazole (2-MBI) into the copper-pyromellitic dianhydride (Cu-PD) interlayer elevated the valence of copper (Cu) ions, which improved the ECO 2 RR performance of Cu-PD-2-MBI. Cu-PD-2-MBI was tested in a flow cell, and the Faradaic efficiency of CH 4 reached 73.7 %, with a corresponding partial current density of −428.3 mA·cm−2 at −1.3 V, which was higher than those of most reported Cu-based catalysts. Further exploration via theoretical calculations indicated that the intercalated 2-MBI in Cu-PD-2-MBI induced a shift in the d-band center in the Cu sites from −2.63 to −1.86 eV and reduced the formation energy of the *COOH and *CHO intermediates in the process of generating CH 4 compared with those of the reference Cu-PD catalyst. [ABSTRACT FROM AUTHOR]

[Display omitted] • A strategy for MOF-composite nanofiber with synergistic architecture is proposed. • PU@PAN/UiO-66 core/shell nanofiber is prepared by coaxial electrospinning. • 3D proton-conduction networks are constructed in proton exchange membrane. • Sulfamic acid is successfully introduced on nanofiber. • The maximum power density of Nafion/S@NF-50 exhibits 182.6 mW cm−2. Proton exchange membranes (PEMs) play an important role in fuel cells. For realizing a nanofiber (NF) structure design in PEMs, the material should have tunable pores and a high specific area. In this study, we attempt to design a novel NF with synergistic architecture doped MOF for constructing three-dimensional (3D) proton conduction networks in PEMs. In this framework, UiO-66-COOH serves as a platform for proton sites to synergistically promote proton conductivity via polyvinylpyrrolidone dissolution, hydrolyzation of polyacrylonitrile, and sulfamic acid functionalization of the shell-layer NF. Benefiting from enriched proton-transfer sites in NFs, the obtained composite membrane overcomes the trade-off among proton conductivity, methanol permeability, and mechanical stability. The composite membrane with 50 % fiber (Nafion/S@NF-50) exhibited a high proton conductivity of 0.212 S cm−1 at 80 °C and 100 % relative humidity, suppressed methanol permeability of 0.66 × 10−7 cm2 s−1, and the maximum power density of direct methanol fuel cell is 182.6 mW cm−2. Density functional theory was used to verify the important role of sulfamic acid in proton transfer, and the activation energy barriers under anhydrous and hydrous conditions are only 0.337 and 0.081 kcal, respectively. This study opens up new pathways for synthesizing NF composite PEMs. [ABSTRACT FROM AUTHOR]

[Display omitted] • Biowaste cinnamon stick was assessed as a sustainable sorbent. • MIL-125 and CMC were utilized for successfully enhancing CV adsorption. • Equilibrium studies were conducted 3 different temperatures. • q max of CMC/MIL-125@CS was calculated as 6750.58 mg/g. • CMC/MIL-125@CS reached equilibrium the fastest with minimum adsorbent dosage. In the current study, a biowaste cinnamon stick (CS) was used as an adsorbent and modified via in-situ techniques with titanium-based metal organic framework (MIL-125@CS) and carboxymethyl cellulose (CMC/MIL-125@CS). The prepared samples were characterized by various techniques, then utilized for toxic crystal violet (CV) dye removal. CV adsorption was examined for the effects of adsorbent dosage, solution pH, contact time, initial concentration, temperature and anion/cation/natural organic material (NOM). CV removal rate remarkably decreased at low pHs due to the degradation of CV and wavelength shift in the strongly acidic region. The kinetic and isotherm results showed that CMC/MIL-125@CS reached equilibrium much faster (30 min) and much higher adsorption capacity (6750.58 mg/g) than CS and MIL-125@CS. Furthermore, the samples were efficiently regenerated and reusable over five cycles, demonstrating significant adsorption rates. Functional material design approaches yielded superior CV adsorption performance. [ABSTRACT FROM AUTHOR]

A new single-atom solid base catalyst, Ca 1 /UiO-67-BPY, is fabricated, in which Ca atoms are immobilized onto N-rich metal–organic framework UiO-67-BPY at room temperature. [Display omitted] Considerable attention has been paid to the preparation of single-atom solid base catalysts (SASBCs) owing to their high activity and maximized utilization of basic sites. At present, the reported fabrication methods of SASBCs, such as two-step reduction strategy and sublimation capture strategy, require high temperature. Such a high activation temperature is easy to cause the sublimation loss of alkali or alkaline earth metal atoms and destructive to the support structure. Herein, a new SASBC, Ca 1 /UiO-67-BPY, is fabricated, in which the alkaline earth metal Ca sites are immobilized onto N-rich metal–organic framework UiO-67-BPY at room temperature. The results show that the atomic configuration of Ca single atoms is coordinated by two N atoms in the framework. The obtained Ca SASBC possesses ordered structure and exhibits high product yield of 87.2% in the Knoevenagel reaction between benzaldehyde and malononitrile. Furthermore, thanks to the Ca single atoms sites anchored on UiO-67-BPY, the Ca 1 /UiO-67-BPY catalyst also shows good stability during cycles. This work might offer new insight in designing SASBCs for different base-catalyzed reactions. [ABSTRACT FROM AUTHOR]

Conductive MIL-101(Cr) PEDOT has been drop cast on interdigitated electrodes. When regularly deposited, the nanoparticles are randomly dispersed on the surface leading to a poor conductivity. When an electric field is applied during the drop casting, the particles are spatioselectively deposited between the finger electrodes, enhancing both the resulting conductivity and sensitivity to water vapor. [Display omitted] Precise deposition of metal–organic framework (MOF) materials is important for fabricating high-performing MOF-based devices. Electric-field assisted drop-casting of poly(3,4-ethylenedioxythiophene)-functionalized (PEDOT) MIL-101(Cr) nanoparticles onto interdigitated electrodes allowed their precise spatioselective deposition as percolating nanoparticle chains in the interelectrode gaps. The resulting aligned materials were investigated for resistive and capacitive humidity sensing and compared with unaligned samples prepared via regular drop-casting. The spatioselective deposition of MOFs resulted in up to over 500 times improved conductivity and approximately 6 times increased responsivity during resistive humidity sensing. The aligned samples also showed good capacitive humidity sensing performance, with up to 310 times capacitance gain at 10 versus 90 % relative humidity. In contrast, the resistive behavior of the unaligned samples rendered them unsuitable for capacitive sensing. This work demonstrates that applying an alternating potential during drop-casting is a simple yet effective method to control MOF deposition for greater efficiency, conductivity, and enhanced humidity sensing performance. [ABSTRACT FROM AUTHOR]

The as-synthesized CQDs-X/NiMOF V heterojunctions exhibit superior performance for CO 2 photoreduction into CH 4 than normal NiMOF and novel NiMOF V catalyst. The highest yielding rate of CH 4 and selectivity is obtained over CQDs-25/NiMOF V catalyst with a value of 1 mmol g−1 h−1 and 97.58 % selectivity, respectively. The superior performance of CQDs-25/NiMOF V may be attributed to the following two factors: (i) Both CQDs and oxygen vacancies facilitate the transmission of electrons to promote the eight-electrons-reaction producing CH 4 , (ii) oxygen vacancies can act as the electron trap to capture the photogenerated electrons to react with adsorbed CO 2 on Ni2+. Moreover, in diluted CO 2 (50 %, 20 %, and 10 %) atmosphere, the yield of CH 4 is almost unchanged and the selectivity of CH 4 over CQDs-25/NiMOF V is apparently higher than that of in pure CO 2. [Display omitted] Solar-light-driven reduction of CO 2 into renewable fuels has great potential in the production of sustainable energy, addressing the energy crisis and environmental problems simultaneously. However, it is a significant challenge to achieve high selectivity for the conversion of CO 2 into CH 4 , which is a type of fuel with a high calorific value. Herein, carbon quantum dots (CQDs) were integrated with an oxygen vacancy modified nickel-based metal organic frameworks (NiMOFs) to form the CQDs-X/NiMOF V series, which exhibited superior performance for CO 2 photoreduction into CH 4 compared with pure NiMOFs in the presence of hole scavengers under visible light irradiation. The highest yielding rate of CH 4 (1 mmol g−1 h−1) and selectivity (97.58 %) were obtained using a CQDs-25/NiMOF V catalyst. Most importantly, in diluted CO 2 atmosphere, the yield of CH 4 was almost unchanged and the selectivity of CH 4 over CQDs-25/NiMOF V was higher than that in pure CO 2. The superior performance of CQDs-25/NiMOF V may be attributed to the following two factors: (i) both CQDs and oxygen vacancies facilitate the transmission of electrons to promote the eight-electron reaction producing CH 4 , and (ii) oxygen vacancies can act as the electron trap to capture the photogenerated electrons to react with adsorbed CO 2 on Ni2+. This study offers a valuable strategy for designing efficient photocatalysts to convert CO 2 into CH 4 with superior selectivity. [ABSTRACT FROM AUTHOR]

[Display omitted] • Optimizing the crystalline structures and electronic properties of NiFe-MOFs by altering the organic ligands. • Ultra-low overpotentials and remarkable stability of NiFe-BDC in alkaline water/seawater. • Deciphering the surface reconstruction by various characterizations and in-situ measurements. • Unique NiFeOOH/NiFe-BDC heterojunction for low reaction barriers and fast reaction kinetics. Metal-organic frameworks (MOFs) have gained tremendous notice for the application in alkaline water/seawater oxidation due to their tunable structures and abundant accessible metal sites. However, exploring cost-effective oxygen evolution reaction (OER) electrocatalysts with high catalytic activity and excellent stability remains a great challenge. In this work, a promising strategy is proposed to regulate the crystalline structures and electronic properties of NiFe-metal-organic frameworks (NiFe-MOFs) by altering the organic ligands. As a representative sample, NiFe-BDC (BDC: C 8 H 6 O 4) synthesized on nickel foam (NF) shows extraordinary OER activity in alkaline condition, delivering ultralow overpotentials of 204, 234 and 273 mV at 10, 100, and 300 mA cm−2, respectively, with a small Tafel slope of 21.6 mV dec−1. Only a slight decrease is observed when operating in alkaline seawater. The potential attenuation is barely identified at 200 mA cm−2 over 200 h continuous test, indicating the remarkable stability and corrosion resistance. In-situ measurements indicate that initial Ni2+/Fe2+ goes through oxidation process into Ni3+/Fe3+ during OER, and eventually presents in the form of NiFeOOH/NiFe-BDC heterojunction. The unique self-reconstructed surface is responsible for the low reaction barrier and fast reaction kinetics. This work provides an effective strategy to develop efficient MOF-based electrocatalysts and an insightful view on the dynamic structural evolution during OER. [ABSTRACT FROM AUTHOR]

[Display omitted] The energy system of lithium-sulfur batteries is quite promising, however, lithium-sulfur batteries still suffer from considerable problems, such as the abominable shuttle effect of polysulfides (LiPSs), the low conductivity of the solid-phase products, the slow redox kinetics during charging and discharging, and the volume expansion. Herein, the hybridization pattern between the d -orbitals of various transition metal atoms and the p -orbitals of sulfides is revealed grounded in the theory of density function, which explains the high adsorption strength of two-dimensional metal–organic frameworks (MOFs) with LiPSs and accelerates the screening of high-performance anchoring and catalytic materials. The results elucidate that the coordinated transition metal–organic frameworks (Mo-NH MOF) monolayers increase the capacity of LiPSs to anchor by forming more π -bonds from the hybridization of the S p orbitals and Mo d orbitals. Notably, Mo-NH MOF exhibits bifunctional catalytic activity for sulfur reduction as well as Li 2 S decomposition reactions during charging and discharging, which improves the conversion efficiency of redox reactions. As a result, new MOF materials featuring unique active centers and the potential mechanism by which the active centers modulate the performance of the substrate materials are revealed, and this finding may accelerate the development of high-performance Li-S batteries. [ABSTRACT FROM AUTHOR]

[Display omitted] Photodynamic therapy (PDT) and catalytic therapy were promising treatment modes, but tumor hypoxia and poor catalytic activity severely limited their efficacies. Herein, using a porphyrin metal–organic framework (PCN-224) as nanocarrier, a platinum/palladium (Pt/Pd) dual-modified PCN-224 nanoprobe (PCN-224-Pt@Pd) with strong peroxidase (POD)/catalase (CAT)-like activities was developed, achieving photothermal-promoted PDT/catalytic therapy. Compared with single ultrasmall Pt modifying, CAT-like activity of Pt/Pd dual-modifying increased oxygen concentration from 6.24 to 9.35 mg/L, which improved singlet oxygen (1O 2) yield from 63.8 % to 82.9 %. Moreover, POD-like activity of Pt/Pd dual-modifying significantly accelerated hydroxyl radicals (·OH) generation. Importantly, PCN-224-Pt@Pd possessed near-infrared II (NIR-II) photothermal effect with a high efficiency (55.6 %), which further promoted ·OH production. Under combined therapy of PCN-224-Pt@Pd, the cell survival rate greatly reduced to 5.8 %, and the tumors were cured, suggesting NIR-II photothermal-enhanced PDT/catalytic therapy. [ABSTRACT FROM AUTHOR]

[Display omitted] Transition metal-coordinated porphyrin metal-organic frameworks (MOFs) were perspective in photodynamic therapy (PDT) and catalytic therapy. However, the tumor hypoxia and the insufficient endogenous hydrogen peroxide (H 2 O 2) seriously limited their efficacies. Herein, by encapsulating ultrasmall iridium (Ir) and modifying glucose oxidase (GOx), an iron-coordinated porphyrin MOF (Fe-MOF) nanoplatform (Fe-MOF@Ir/GOx) was designed to strengthen PDT/catalytic therapy by producing reactive oxygen species (ROS) storm. In this nanoplatform, Fe-MOF showed glutathione (GSH)-responsive degradation, by which porphyrin, GOx and ultrasmall Ir were released. Moreover, ultrasmall Ir possessed dual-activities of catalase (CAT)-like and peroxidase (POD)-like, which provided sufficient oxygen (O 2) to enhance PDT efficacy, and hydroxyl radical (·OH) production was also improved by combining Fenton reaction of Fe2+. Further, GOx catalyzed endogenous glucose produced H 2 O 2 , also reduced pH value, which accelerated Fenton reaction and resulted in generation of ROS storm. Therefore, the developed Fe-MOF@Ir/GOx nanoplatform demonstrated enhanced PDT/catalytic therapy by producing ROS storm, and also provided a promising strategy to promote degradation/metabolism of inorganic nanoplatforms. [ABSTRACT FROM AUTHOR]

[Display omitted] • MOF nanosheets reconfigured by electrostatic coupling and interfacial conditioning strategies. • PEDOT:PSS and MOF nanosheets with interoperable conductive network and excellent interfacial properties. • MOF nanosheets attenuate the entanglement of PEDOT:PSS. • Homogeneous ink prepared using solution engineering for flexible supercapacitor preparation. Two-dimensional metal – organic frameworks (2D MOFs) hold great promise as electrochemically active materials. However, their application in MOF nanocomposite electrodes in solution engineering is limited by structural self-stacking and imperfect conductive pathways. In this study, we used meso -tetra(4-carboxyphenyl) porphine (TCPP) with off-domain π-bonds to reconstitute Zn-TCPP (ZMOF) and poly(3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS) through an interfacial modulation strategy involving electrostatic coupling and hydrogen bonding, creating a conductive composite with a nanosheet structure. The negatively charged PSS and ZMOF formed a three-dimensional interconnected conductive network with excellent interfaces. The positively charged PEDOT, fine tuned with the lamellar structure, established strong π-π stacking interactions between the porphyrin and thiophene rings. ZMOF also induced changes in the PEDOT chain structure, weakening PSS entanglement and enhancing charge-transport properties. The specific capacitance of the prepared supercapacitor was as high as 967.8 F g−1. Flexible supercapacitors produced on a large scale using dispensing printing technology exhibited an energy density of 1.85 μWh cm−2 and a power density of 7.08 μW cm−2. This interfacial modulation strategy also exhibited excellent wearable properties, with 96 % capacitance retention at a 180° bending angle and stable cycling performance. This study presented a significant advancement in the functionalization of 2D materials, highlighting their potential for device-grade capacitive architectures. [ABSTRACT FROM AUTHOR]

[Display omitted] Zeolitic imidazolate frameworks (ZIFs), a class of promising metal organic frameworks (MOFs) material, display high porosity and chemical/thermal stability. However, there are problems such as few active sites and restricted exposed active areas, which limit the oxygen evolution reaction (OER) performance of catalysts. Here, starting from zeolitic imidazolate framework-67 (ZIF-67), we have successfully synthesized Pt-doped CoFe layered double hydroxide (Pt/CoFe LDH) catalysts for efficient OER catalysis. The obtained Pt/CoFe LDH-4 catalysts provides large surface areas and abundant active sites, which further improves the OER performance. In detail, the Pt/CoFe LDH-4 exhibits a lower overpotential of 263 mV at a current density of 40 mA cm−2, in 1 M KOH solution, the stability of the catalyst exceeds 120 h at this current density, far superior to commercial catalyst RuO 2. This study describes a new design idea for synthesis of LDH catalytic materials with low noble metal doping, which broadens the way to the synthesis of robust OER catalysts derived from ZIF-67. [ABSTRACT FROM AUTHOR]

[Display omitted] • Using MOF as a precursor to obtain mesopore-rich titanium dioxide and achieve uniform copper dispersion. • The porous structure is beneficial to expose copper nanoparticle to improve atom utilization. • Use Cu as both dopant and co-catalyst to enhance hydrogen production activity. Metal-doping is a common strategy for establishing active sites on photocatalyst, but appropriately exposing them for maximized atomic utilization remains a great challenge in photocatalytic research. Herein, we propose a metal organic framework (MOF)-assisted approach to synthesis copper-modified titania (Cu-TiO 2 /Cu) photocatalyst with homogenously distributed and highly accessible active sites in its matrix. Significantly, an MOF precursor, namely NH 2 -MIL-125, with co-chelation of titania (Ti) and copper (Cu) was subjected to mild calcination, subsequently results in Cu-modified TiO 2 with highly accessible channels to its inner surface. These channels provide not only a large reactive surface (>400 m2 g-1); they also enable facile modifying route for the pre-deposited Cu in prior to photoreaction. Specifically, NH 3 treatment was applied to partially reduce deposited Cu ions (Cu+ and Cu2+) into Cu nanoparticles, where their interplays realize improved optical properties and charge separation during photoreactions. Furthermore, the NH 3 -induced Cu nanoparticles could also serve as the adsorptive site for H+, thereby enabling 5629 μmol h-1 g-1 H 2 generation over the optimum photocatalyst of Cu 20 /TiO 2 /Cu 500. Such performance is associated to 35.44 and 1.71-fold improvements compared to pure TiO 2 (Cu 0 /TiO 2) and untreated Cu-ion modified TiO 2 (Cu 20 /TiO 2), respectively. This work offers a new synthetic strategy for obtaining photocatalyst with evenly distributed and highly accessible active sites, thus improving the commensurability of photocatalytic H 2 generation from the industrial perspective. [ABSTRACT FROM AUTHOR]

[Display omitted] In CO 2 electroreduction, mutative intermediates and the challenging C C coupling necessitate the spatial interplay between active sites and through dynamically optimizing configurations. Herein, we anchor ethylenediaminetetraacetic acid (EDTA)-bonded Cux+/Bi3+ pair within UiO-66 for a spontaneous spatial-optimizing CO 2 -to-C 2 H 4 electroreduction. Ab initio molecular dynamic (AIMD) simulation visualizes that such metal pair adaptively interacts with intermediates. Density functional theory (DFT) elicits the componential synergy, in which an upshift d-band of Cu activates CO 2 being protonated into *COOH while Bi site stabilizes oxygenated dimers for deep hydrogenation. The dynamic feature of such pair affords large freedom for sorption and migration of various intermediates, which consequently bestows UiO-66-EDTA/CuBi a maximal FE C 2 H 4 of 47 % and a total current density over 100 mA cm−2 in the flow cell. [ABSTRACT FROM AUTHOR]

[Display omitted] • Dual-layers surface engineering of metal–organic frameworks (MOFs) nanoparticles incorporating lipid coating is presented for miRNA efficient delivery, circumventing the pore size limitation of MOFs pore encapsulation. • This layer-by-layer nanostructure sandwiched the miRNA between the MOFs core and lipid surface layer, enhancing stability of miRNA against biodegradation, but also rendering itself with improved colloidal stability, cellular uptake and lysosomal escape. • A versatile approach combines the MOF-based photodynamic therapy, miRNA gene therapy and pre-encapsulated doxorubicin chemotherapy, which synergistically works against cancer cells. MicroRNAs (miRNAs) are small noncoding RNAs that are critical for the regulation of multiple physiological and pathological processes, thus holding great clinical potential. However, the therapeutic applications of miRNAs are severely limited by their biological instability and poor intracellular delivery. Herein, we describe a dual-layers surface engineering strategy to design an efficient miRNA delivery nanosystem based on metal–organic frameworks (MOFs) incorporating lipid coating. The resulting nanoparticle system was demonstrated to protect miRNA from ribonuclease degradation, enhance cellular uptake and facilitate lysosomal escape. These ensured effective miRNA mediated gene therapy, which synergized with MOF-specific photodynamic therapy and pre-encapsulated doxorubicin (Dox) chemotherapy to provide a multifunctional with therapeutic effectiveness against cencer cells The mechanisms of miRNA binding and Dox loading were revealed, demonstrating the potential of the present MOFs surface-engineered strategy to overcome their inherent pore-size restriction for macromolecular miRNA carrying, enableefficient co-delivery. In vitro studies revealed the potential of our multifunctional system for miRNA delivery and the demonstrated the therapeutic effectiveness against cancer cells, thereby providing a versatile all-in-one MOFs strategy for delivery of nucleic acids and diverse therapeutic molecules in synergistic therapy. [ABSTRACT FROM AUTHOR]

[Display omitted] • ZIF-67 derivative and GO co-modified enhanced the visible light catalytic performance of Bi 12 O 17 Cl 2. • Bi 12 O 17 Cl 2 /GO/Co 3 O 4 exhibits good activity, salt resistance, universality and water adaptability to antibiotics degradation. • A pH drift method measures the surface charge of Bi 12 O 17 Cl 2 /GO/Co 3 O 4. • The Z-scheme heterojunction photocatalytic mechanism for Bi 12 O 17 Cl 2 /GO/Co 3 O 4 is analyzed. • Three possible degradation pathways of levofloxacin by Bi 12 O 17 Cl 2 /GO/Co 3 O 4 are proposed. Levofloxacin (LVX) is difficult to be naturally degraded by microorganisms in water, and its residues in water will pose significant risks to human health and ecological environment. In this study, Bi 12 O 17 Cl 2 was used as the main body, Bi 12 O 17 Cl 2 /GO/Co 3 O 4 composite photocatalyst was prepared by pyrolysis of zeolitic imidazolate framework-67 (ZIF-67) combined with in-situ precipitation method and used to degrade LVX. A sequence of characterizations shows that addition of Co 3 O 4 and graphene oxide (GO) increases the visible light response range, improves the separation efficiency of photogenerated electrons and holes (e--h+) of photocatalyst, and thus improves the degradation efficiency of LVX. Under the optimal reaction conditions, the LVX degradation rate of Bi 12 O 17 Cl 2 /1.5GO/7.5Co 3 O 4 can reach 91.2 % at 120 min, and its reaction rate constant is the largest (0.0151 min−1), which is 2.17, 13.14 and 1.53 times that of Bi 12 O 17 Cl 2 , Co 3 O 4 and Bi 12 O 17 Cl 2 /7.5Co 3 O 4 , respectively, showing better photocatalytic performance. Simultaneously, the recycling stability of Bi 12 O 17 Cl 2 /1.5GO/7.5Co 3 O 4 was also verified. The capture experiments and electron EPR test results showed that superoxide radicals (•O 2 –) and photogenerated holes (h+) were the primary active substances in the reaction process. Finally, combined with HPLC-MS results, the photocatalytic degradation pathway of LVX was derived. This work will provide a theoretical basis for the design of Metal Organic Frameworks (MOFs)-derivative modified Bi 12 O 17 Cl 2 -based photocatalysts. [ABSTRACT FROM AUTHOR]

Cobalt tetrafluoroborate was proposed as a novel bi-functional precursor for synthesizing ZIF-67 derivatives, and interactions between solvent molecules and solutes on morphology, composition, and electrochemical performance are investigated. [Display omitted] • Co(BF 4) 2 is proposed as a novel cobalt precursor to synthesize ZIF67 derivatives. • Co(BF 4) 2 can supply cobalt ions and structure directing agent function from BF 4 −. • Deionic water, methanol and ethanol are used as precursor solvent to study effect. • The optimal derivative presents a specific capacitance of 608.3 F/g at 20 mV/s. • A battery supercapacitor hybrid shows maximum energy density of 45 Wh/kg@429 W/kg. Metal-organic framework (MOF) derivatives with tunable pore structure and improved conductivity are intensively designed as electroactive materials. Incorporating structure directing agents (SDA) is beneficial for designing MOF derivatives with excellent electrochemical performances. Ammonium fluoroborate has been reported as an effective SDA, coupled with cobalt salt and 2-methylimidazole, to synthesize zeolitic imidazolate framework-67 (ZIF-67) derivatives for charge storage. However, the synthetic environment for growing cobalt-based active materials is relatively complex. In this study, cobalt tetrafluoroborate (Co(BF 4) 2) is proposed as a novel cobalt precursor, supplementing cobalt ions and acting as the SDA in a single chemical, to synthesize the cobalt-based electroactive material of energy storage electrodes. Interactions between solvent molecules and solutes play significant roles on the morphology, composition, and electrochemical performance of active materials. Deionized water, methanol and ethanol are used as precursor solvents to understand their effects on material and electrochemical properties. The optimal electrode presents a specific capacitance of 608.3 F/g at 20 mV/s, attributed to the highest electrochemical surface area and evident compositions of cobalt fluoride and hydroxide. A battery supercapacitor hybrid achieves the maximum energy density of 45 Wh/kg at 429 W/kg. The C F retention of 100% and Coulombic efficiency of 99% are achieved after 10,000 cycles. [ABSTRACT FROM AUTHOR]

Cu-MOF is grown in-situ on surface of corncob-derived hydrothermal carbon sphere to form a uniform Cu-MOF outer layer of nanostructured. A structure with an outer layer of Cu-MOF derived carbon composite and an inner layer of corncob-derived charcoal is then designed by heat treatment, in which copper oxide nanoparticles are uniformly distributed in the outer layer. This preparation strategy greatly improves the exposure and openness of the copper oxide sites, and the obtained materials exhibit high specific surface area, rich void structure, and outstanding electrochemical properties. [Display omitted] • The method enables in-situ growth of nanosized MOFs on the surface of biochar. • The strategy mitigates the issue of metal sites being occluded by excess carbon, enhancing the metal atom utilization ratio. • Composite material has high specific surface area and graded pore structure. • Composite material as electrode exhibits large specific capacitance, excellent rate capability, and cycle stability. • High atom economy strategy is versatile and can be applied to a wide range of biochar and MOFs. Carbon/metal composites derived from metal-organic frameworks (MOFs) have attracted widespread attention due to their excellent electronic conductivity, adjustable porosity, and outstanding stability. However, traditional synthesis methods are limited by the dense stereo geometry and large crystal grain size of MOFs, resulting in many metals active sites are buried in the carbon matrix. While the common strategy involves incorporating additional dispersed media into material, this leads to a decrease in practical metal content. In this study, nanosized copper-metal-organic frameworks (Cu-MOFs) are in-situ grown on surface of carbon spheres by pre-anchoring copper ions, and the hybrid composite of porous carbon/copper oxide with high copper atom utilization rate is prepared through activation and pyrolysis methods. This strategy effectively addresses the issue of insufficient exposure of metal sites, and the obtained composite material exhibits high effective copper atom utilization rate, large specific surface area (2052.3 m2·g−1), diverse pore structure, outstanding specific capacity (1076.5F·g−1 at 0.5 A·g−1), and excellent cycle stability. Furthermore, this highly atom-economical universal method has positive significance in application fields of catalysis, energy storage, and adsorption. [ABSTRACT FROM AUTHOR]

[Display omitted] Multinary metal sulfides (MMSs) are highly suitable candidates for the application of electrocatalysis as they offer numerous parameters for optimizing the electronic structure and catalytic sites. Herein, a stable nanoarchitecture consisting of MMSs ((NiCoCrMnFe)S x) nanoparticles embedded in S, N-codoped carbon (SNC) layers derived from metal organic framework (MOF) and supported on carbonized wood fibers (CWF) was fabricated by directly carbonization. Benefiting from this carbon-coated configuration, along with the synergistic effects within multinary metal systems, (NiCoCrMnFe)S x @SNC/CWF delivers an exceptionally low overpotential of 260 mV at a high current density of 1000 mA cm−2, a small Tafel slope of 48.5 mV dec−1, and robust electrocatalytic stability. Furthermore, the (NiCoCrMnFe)S x @SNC/CWF used as the cathode of rechargeable Zn-air batteries demonstrates higher power density and remarkable durability, surpassing that of commercial RuO 2. Thus, we showcase the feasibility and advantages of employing highly efficient and durable MMSs materials for low-cost and sustainable energy conversion. [ABSTRACT FROM AUTHOR]

FeN 3 -CoN 3 sites break the symmetric electron distribution of single atom sites optimizing adsorption energies of oxygen intermediates. As a result, FeCo-NC exhibits extraordinary ORR activity with a high half-wave potential of 0.915 V in alkaline electrolyte. [Display omitted] Single-atom catalysts show good oxygen reduction reaction (ORR) performance in metal-air battery. However, the symmetric electron distribution results in discontented adsorption energy of ORR intermediates and a lower ORR activity. Herein, Fe-Co dual-atom catalyst with FeN 3 -CoN 3 configuration was prepared by encapsulating nitrogen-rich ion (triethylenediamine cobalt complex, [Co(en) 3 ]3+) in Fe based MOF cage to greatly enhance ORR performance. Due to the confinement effect of the MOF cage, the encapsulated [Co(en) 3 ]3+ is closer to Fe of MOF, thus easily generating FeN 3 -CoN 3 sites. The FeN 3 -CoN 3 sites can break the symmetric electron distribution of single-atom sites, optimizing adsorption energy of oxygen intermediate. Thus, FeCo-NC exhibits extraordinary ORR activity with a high half-wave potential of 0.915 V and 0.789 V in alkaline and acidic electrolyte, respectively, while it was 0.874 V and 0.79 V for Pt/C. The liquid and solid Zn-air batteries with FeCo-NC as cathode show higher peak power density and specific capacity. DFT results indicate that FeN 3 -CoN 3 site can reduce the reaction energy barrier of the rate-determining step resulting in an excellent ORR performance. [ABSTRACT FROM AUTHOR]

In this work, a unique tri-metal (Co/Fe/Ni) layered double hydroxide hollow array anode catalyst (CFN-LDH/NF) and the CoP/FeNi 2 P heterojunction hollow array cathode are successfully prepared via one in-situ growth of Co-MOF on nickel foam (Co-MOF/NF) precursor, which exhibits excellent catalytic performance of OER η 1000 (CFN-LDH/NF) of 352 and 392 mV in 1.0 M KOH and alkaline seawater solution and HER η 1000 (CFNP/NF) of 281 and 312 mV in 1.0 M KOH and alkaline seawater solution. [Display omitted] The seawater electrolysis technology powered by renewable energy is recognized as the promising "green hydrogen" production method to solve serious energy and environmental problems. The lack of low-cost and ampere-level current OER (oxygen evolution reaction) and HER (hydrogen evolution reaction) catalysis limits their industrial application. In this work, a unique tri-metal (Co/Fe/Ni) layered double hydroxide hollow array anode catalyst (CFN-LDH/NF) and the CoP/FeNi 2 P heterojunction hollow array cathode are successfully prepared via one in-situ growth of Co-MOF on nickel foam (Co-MOF/NF) precursor, which exhibits excellent catalytic performance. The η 1000 values of 352 and 392 mV are achieved for CFN-LDH/NF (OER catalyst) in 1.0 M KOH and alkaline seawater solution, respectively. The CFNP/NF with a low overpotential of 281 mV is required to reach 1000 mA cm−2 current density for HER in 1.0 M KOH solution, while the η 1000 in alkaline seawater solution is 312 mV. The CFN-LDH/NF||CFNP/NF electrolyzer exhibits excellent long-term durability over 100 h, achieving current density of 500 mA cm−2 at 1.825 V in 1.0 M KOH solution. The construction of hollow tri-metal LDH and phosphides heterostructures may open a new and relatively unexplored path for fabricating high performance seawater splitting catalysis. [ABSTRACT FROM AUTHOR]

This study proposes a novel strategy to modulate the morphology and electronic structure of MOFs through ligand exchange for high-performance energy storage and conversion devices. The prepared CoNi-TDA/0.2Fc had an oxygen generation reaction (OER) overpotential of 236 mV at 10 mA cm−2 and a significant specific capacitance of 1409 F−1 at 1 A/g, maintaining a capacitance retention of 96.54% after 20,000 cycles. [Display omitted] Rationally designing metal organic frameworks (MOFs) as an ideal dual-function material for water electrolysis and supercapacitors is of great significance for energy storage and conversion. Herein, we successfully synthesized the nanoneedle-like structure CoNi-MOF by partially replacing 2, 5-thiophenedicarboxylic acid (TDA) with 1, 1′-Ferrocenedicarboxylate (Fc). The exchange of Fc ligand can modulate the morphology and electronic structure of CoNi-TDA, thus exposing the abundant active sites and improving the electrical conductivity. The as-prepared CoNi-TDA/0.2Fc exhibited a low overpotential of 236 mV at 10 mA cm−2 for oxygen evolution reaction (OER) and a low Tafel slope of 40.44 mV dec−1. Additionally, CoNi-TDA/0.2Fc demonstrated a notable specific capacitance of 1409 F g−1 at 1 A/g and excellent stability, maintaining a capacitance retention of 96.54 % after 20,000 cycles. The study proposes a new strategy to modulate the morphology and electronic structure of MOFs via the ligand exchange for high-performance energy storage and conversion device. [ABSTRACT FROM AUTHOR]

[Display omitted] • Inspired by the nature, a sea urchin-like IL modified UiO-66 was obtained. • The optimized sensor exhibits high response and ultra-fast response speed in the low humidity range of 0–35% RH. • The sensing mechanism is fully investigated through DFT calculation. • The low humidity sensor was proved to have applications in visual humidity detection and water source location. Numerous applications require low humidity sensors that not only sensitive but also stable, small hysteresis, high resolution and fast response. However, most reported low humidity sensors cannot possess these properties at the same time. In this work, inspired by sea urchin, we developed an ionic liquid (IL) modified metal organic framework (UiO-66) based low humidity sensor. Owing to the synergistic effect of the hydrophilicity and ionic conductivity of IL and the steric hindrance effects of UiO-66, the optimized low humidity sensor simultaneously exhibits high response (47.5), small hysteresis (0.3 % RH), ultrafast response speed (0.2 s), high resolution (1 % RH), and excellent long-term stability (>120 days). In particular, the sensor has been proved to have potential applications in visual humidity detection and water source location. This work provides a preliminary design principle that will contribute to the preparation of high-performance low humidity sensing materials. [ABSTRACT FROM AUTHOR]