A renewable screen-printed electrode based on magnetic NiCo@N-doped carbon nanotubes derived from Co-MOF for ractopamine detection.

A renewable electrochemical screen-printed electrode (SPE) is proposed based on magnetic bamboo-like nitrogen-carbon (N-C) nanotubes loaded with nickel-cobalt alloy (NiCo) nanoparticles (NiCo@N-CNTs) for the determination of ractopamine (RAC). During the preparation of NiCo@N-CNTs, Co-MOF-67 (ZIF-67) was firstly synthesized, and then blended with dicyandiamide and nickel acetate, followed by a one-step pyrolysis procedure to prepare NiCo@N-doped carbon nanotubes. The surface morphology, structure, and chemical composition of NiCo@N-CNTs were characterized by SEM, TEM, XRD, XPS, and EDS. The electrocatalytic and electrochemical behavior of NiCo@N-CNTs were investigated by cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). The results demonstrated that NiCo@N-CNTs possessed remarkable conductivity and electrocatalysis to the oxidation of ractopamine (RAC). By using screen-printed electrode (SPE), NiCo@N-CNTs, and a designed base support, a magnetic RAC sensor (NiCo@N-CNTs/SPE) was successfully constructed. It presented a detection linear range of 0.05-80 µM with a detection limit of 12 nM (S/N = 3). It also exhibited good sensitivity, reproducibility, and practicability in spiked real pork samples. Since the adhesion of NiCo/N-CNTs on SPE was controlled by magnet, the NiCo@N-CNTs was easily detached from the SPE surface by magnetism and thus displayed excellent renewability. This work broadened insights into portable devices for on-site and real-time analysis.

An innovative triple interface reinforced photocatalytic system based on BiOCl/BaTiO3@Co-BDC-MOF composite for the simultaneous detoxification of Cr(VI) and sulfamethoxazole.

The development of effective photocatalysts for the reduction of Cr(VI) and the degradation of antibiotics remains a challenge. The present work reports the development of a novel heterojunction composite material, BiOCl/BaTiO3@Co-BDC-MOF (BOC/BTO@Co-MOF), based on solvothermal techniques. To characterize the surface and bulk features of the material, techniques such as FE-SEM, HR-TEM, BET/BJH, XPS, FT-IR, p-XRD, and UV-Vis-DRS were used. Based on the results, the BiOCl/BaTiO3 nanocomposites are uniformly dispersed on the rod-shaped Co-BDC MOF, resulting in a layered texture on the surface. A further advantage of the composite structure is the strong interfacial enhancement facilitating the separation of photoexcited electron-hole pairs. Also, compared to its pristine counterparts, the heterostructure material exhibited excellent surface area and pore properties. The photocatalytic efficiency towards reduction and degradation of Cr(VI)/SMX pollutants were evaluated by optimizing various analytical parameters, such as pH, catalytic loading concentrations, analyte concentration, and scavenger role. The specially designed BOC/BTO@Co-MOF composite achieved a 96.5% Cr(VI) reduction and 98.2% SMX degradation under 60.0-90.0 min of visible light illumination at pH 3.0. This material is highly reusable and has a six-time recycling potential. The findings of this study contribute to a better understanding of the efficient decontamination of inorganic and organic pollutants in water purification systems.

Cu-Co bimetallic organic framework as effective adsorbents for enhanced adsorptive removal of tetracycline antibiotics.

In this study, the removal effect of a new MOF-on MOF adsorbent based on Cu-Co bimetallic organic frameworks on tetracycline antibiotics (TCs) in water system was studied. The adsorbent (Cu-MOF@Co-MOF) were synthesized by solvothermal and self-assembly method at different concentrations of Co2+/Cu2+. The characterization results of SEM, XRD, XPS, FTIR and BET indicated that the MOF-on MOF structure of Cu-MOF@Co-MOF exhibited the best recombination and physicochemical properties when the molar ratio of Co2+: Cu2+ is 5:1. In addition, the Cu-MOF@Co-MOF have a high specific surface area and bimetallic clusters, which can achieve multi-target synergistic adsorption of TCs. Based on above advantages, Cu-MOF@Co-MOF provided a strong affinity and could efficiently adsorb more than 80% of pollutants in just 5 to 15 min using only 10 mg of the adsorbent. The adsorption capacity of tetracycline and doxycycline was 434.78 and 476.19 mg/g, respectively, showing satisfactory adsorption performance. The fitting results of the experimental data were more consistent with the Langmuir isotherm model and pseudo-second-order kinetic model, indicating that the adsorption process of TC and DOX occurred at the homogeneous adsorption site and was mainly controlled by chemisorption. Thermodynamic experiments showed that Cu-MOF@Co-MOF was thermodynamically advantageous for the removal of TCs, and the whole process was spontaneous. The excellent adsorption capacity and rapid adsorption kinetics indicate the prepared MOF-on MOF adsorbent can adsorb TCs economically and quickly, and have satisfactory application prospects for removing TCs in practical environments. The results of the study pave a new way for preparing novel MOFs-based water treatment materials with great potential for efficient removal.

Aerophobic P-MoS2 on MOF-Derived Co,N-Codoped Carbon Nanosheets with Accelerated H2 Bubble Release Dynamics for Efficient Alkaline Water Splitting at 1000 mA cm-2.

Rapid bubble release at high current densities results in the detachment of catalysts and performance degradation, posing a persistent challenge in actual alkaline water electrolysis (AWE). Here, hierarchical nanosheet structures (CoNC@P-MoS2) are constructed, with P-doped MoS2 on the surface of Co,N-codoped carbon. It exhibits low hydrogen evolution reaction overpotentials of 30 and 354 mV at 10 and 1000 mA cm-2 in 1 M KOH, respectively, with a small Tafel slope of 36 mV dec-1. The constructed CoNC@P-MoS2||NiFe-DLH cell requires only 1.44 and 1.92 V to achieve overall water splitting at 10 and 1000 mA cm-2, which outperforms the traditional catalysts like Pt/C||IrO2. The introduction of P stabilizes surface hydroxyl (OH*) and increases the proton penetration depth, thereby greatly enhancing its intrinsic activity. It also makes the surface aerophobic by introducing more microfeatures, which greatly improves the geometric activity by increasing the bubble release rate (∼5.8 times). Low energy consumption of 3.92 kW h Nm-3 was achieved with an energy efficiency close to 80%. Bubble growth kinetics analysis reveals that the time and growth factors for CoNC@P-MoS2 are increased to 0.54 and 11.79 from 0.45 and 6.09 for CoNC, respectively, which highlights its fast bubble reaction dynamics. The results suggest the feasibility of CoNC@P-MoS2 as a potential high-performance catalyst in commercial AWE.

A Co-MOF encapsulated microneedle patch activates hypoxia induction factor-1 to pre-protect transplanted flaps from distal ischemic necrosis.

Avoiding ischemic necrosis after flap transplantation remains a significant clinical challenge. Developing an effective pretreatment method to promote flap survival postoperatively is crucial. Cobalt chloride (CoCl2) can increase cell tolerance to ischemia and hypoxia condition by stimulating hypoxia-inducible factor-1 (HIF-1) expression. However, the considerable toxic effects severely limit the clinical application of CoCl2. In this study, cobalt-based metal-organic frameworks (Co-MOF) encapsulated in a microneedle patch (Co-MOF@MN) was developed to facilitate the transdermal sustained release of Co2+ for rapid, minimally invasive rapid pretreatment of flap transplantation. The MN patch was composed of a fully methanol-based two-component cross-linked polymer formula, with a pyramid structure and high mechanical strength, which satisfied the purpose of penetrating the skin stratum corneum of rat back to achieve subcutaneous vascular area administration. Benefiting from the water-triggered disintegration of Co-MOF and the transdermal delivery via the MN patch, preoperative damage and side effects were effectively mitigated. Moreover, in both the oxygen-glucose deprivation/recovery (OGD/R) cell model and the rat dorsal perforator flap model, Co-MOF@MN activated the HIF-1α pathway and its associated downstream proteins, which reduced reperfusion oxidative damage, improved blood supply in choke areas, and increased flap survival rates post-transplantation. This preprotection strategy, combining MOF nanoparticles and the MN patch, meets the clinical demands for trauma minimization and uniform administration in flap transplantation. STATEMENT OF SIGNIFICANCE: Cobalt chloride (CoCl2) can stimulate the expression of hypoxia-inducible factor (HIF-1) and improve the tolerance of cells to ischemia and hypoxia conditions. However, the toxicity and narrow therapeutic window of CoCl2 severely limit its clinical application. Herein, we explored the role of Co-MOF as a biocompatible nanocage for sustained release of Co2+, showing the protective effect on vascular endothelial cells in the stress model of oxygen-glucose deprivation. To fit the clinical needs of minimal trauma in flap transplantation, a Co-MOF@MN system was developed to achieve local transdermal delivery at the choke area, significantly improving blood supply opening and flap survival rate. This strategy of two-step delivery of Co2+ realized the enhancement of biological functions while ensuring the biosafety.

Electrochemiluminescent assay based on Co-MOF and TiO2 for determination of bisphenol A.

An electrochemiluminescence (ECL) sensor for determining bisphenol A (BPA) was prepared based on titanium dioxide (TiO2) and Co-MOF. TiO2 is a co-reaction promoter that amplifies the ECL signal in the Ru(bpy)32+-trinpropylamine (TPrA) system. When the electrode is modified with Co-MOF the ECL signal is significantly enhanced. This is because Co-MOF can not only be used as a co-reaction accelerator but also as a carrier to adsorb more luminescent substances. Possible mechanisms for amplifying the original signal through the synergistic action of the two substances are investigated. The ECL strength decreases with increasing concentrations of BPA, and the amount of BPA can be determined by the change in ECL signal strength (ΔI). Under optimal experimental conditions, the linear range of BPA was 2.0 × 10-10 to 2.0 × 10-5 M, with a determination limit of 6.7 × 10-11 M (3σ/m). The relative standard deviation (RSD) of the signal for ten consecutive measurements was 1.5%. The sensor can be used to detect BPA in bottled samples with recoveries of 96 to 105%.

Generation of a specific aptamer for accurate detection of sarafloxacin based on fluorescent/colorimetric/SERS triple-readout sensor.

Sarafloxacin (SAR), one of the most widely used fluoroquinolone antibiotics, is a serious threat to aquatic environments and human health due to its illegal abuse. Herein, we first screened an aptamer (SAR-1) that specifically binds to SAR using capture-SELEX technology. Based on molecular docking technology, SAR-1 was gradually truncated, and a short SAR-1a with better affinity and specificity was obtained. The optimal SAR-1a was further combined with a Pt nanoparticle (Pt NP)- decorated bimetallic Fe/Co-MOF to fabricate a multimode sensing platform for SAR determination. The Fe/Co-MOF@Pt NPs exhibited excellent peroxidase-like activity, which catalyzed the H2O2-mediated oxidation of 3,3',5,5'-tetramethylbenzidine (TMB), thereby enabling visual detection of SAR. Meanwhile, the generated oxTMB can also produce SERS responses and be used for the SERS detection of SAR. Moreover, the inherent fluorescence property of Fe/Co-MOF@Pt NPs enabled fluorescence detection of SAR. The designed triple-readout aptasensor showed good sensitivity for SAR detection with limits of detection of 0.125 ng/mL (fluorescent mode) and 0.05 ng/mL (colorimetric and SERS mode). The aptamer-based triple-mode sensing platform provided mutual verification of detection results in different output modes, effectively improving the assay accuracy and providing a promising tool for highly sensitive, selective, and accurate determination of SAR in daily life.

Cobalt-based metal-organic framework-functionalized graphene oxide modified electrode as a new electrochemical sensing platform for detection of free chlorine in aqueous solution.

This work reports the profit of using a MOF compound for developing a sensitive electrochemical sensor to free chlorine detection in an aqueous solution. Co-MOF and FGO composites were synthesized and combined with the carbon paste (CP) to prepare an efficient electrochemical sensor with high sensing ability. The fabricated Co-MOF and FGO composites were characterized by SEM, EDX, FT-IR, and XRD techniques. Meanwhile, cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) were utilized to assess the electrochemical performance of the Co-MOF-FGO/CP modified electrode. Under the optimized condition, the amperometric detection showed that the reduction current of free chlorine increased linearly with a coefficient determination of 0.995 during its wide concentration range of 0.1-700 ppm. Also the detection limit (LOD) (S/N = 3) was 0.01 ppm. The selectivity of the sensor was tested with possible interferences, and satisfactory results were obtained. The proposed sensor was successfully used to determine the free chlorine in tap water and swimming pool water real samples. The results suggested that this proposed sensor could pave the way for developing the electrochemical sensor of free chlorine in aqueous media with MOFs.

Zn-Co metal organic frameworks coated with chitosand and Au nanoparticles for chemo-photothermal-targeted combination therapy of liver cancer.

The toxic effects of chemotherapy drugs on normal tissues are still a major limiting factor in cancer treatment. In this paper, we report a metal-organic framework (Zn-Co ZIF) with chitosan-coated outer layer as a carrier for the drug adriamycin hydrochloride (DOX), a treatment for liver cancer, as a novel anti-cancer nanodrug-enhanced carrier. Gold nanoparticles, a good photothermal conversion agent, were combined with the target SH-RGD during surface functionalisation to prepare Zn-Co ZIF@DOX-CS-Au-RGD (ZD-CAR), a nanoplatform with good photothermal conversion properties and targeting for combined liver cancer therapy. ZD-CAR was developed after RGD accurately targeted the tumour and entered the tumour microenvironment (TME), it cleaves and releases the liver cancer therapeutic agent (DOX) in a weak acidic environment to effectively kill tumour cells. The metal skeleton cleavage releases Co2+, which catalyzes the production of oxygen from H2O2 to alleviate the tumour hypoxic environment. The dissolved oxygen could reach 14 mg/L after adding 80 mg/mL of ZD-CAR. Meanwhile, gold nanoparticles could convert light energy into heat energy under 808 NIR irradiation to induce local superheating and kill tumour cells. In summary, this study developed a nanoplatform that combines chemo-photothermal-targeted therapy. It has shown good therapeutic effeciency in cellular experiments and performance tests and has promising applications in anti-cancer therapy.

Bimetallic Cobalt-Nickel Selenide Nanocubes Embedded in a Nitrogen-Doped Carbon Matrix as an Excellent Li-Ion Battery Anode.

Lithium-ion batteries (LIBs) have been widely used for portable electronics and electric vehicles; however, the low capacity in the graphite anode limits the improvement of energy density. Transition-metal selenides are promising anode material candidates due to their high theoretical capacity and controllable structure. In this study, we successfully synthesize a bimetallic transition-metal selenide nanocube composite, which is well embedded in a nitrogen-doped carbon matrix (denoted as CoNiSe2/NC). This material shows a high capacity and excellent cycling for Li-ion storage. Specifically, the reversible capacity approaches ∼1245 mA h g-1 at 0.1 A g-1. When cycled at 1 A g-1, the capacity still remains at 642.9 mA h g-1 even after 1000 cycles. In-operando XRD tests have been carried out to investigate the lithium storage mechanism. We discover that the outstanding performance is due to the unique CoNiSe2/NC nanocomposite characteristics, such as the synergistic effect of bimetallic selenide on lithium storage, the small particle size, and the stable and conductive carbon structure. Therefore, this morphology structure not only reduces the volume change of metal selenides but also produces more lithium storage active sites and shortens lithium diffusion paths, which results in high capacity, good rate, and long cycling.

A functional cobalt-organic framework constructed by triphenylamine tricarboxylate: Detect nitroaromatics by fluorescence sensing and UV-shielding.

Luminescent metal-organic frameworks (LMOF) with ligand-modified are a promising strategy to be applied to fabricate chemical sensors. Herein, a novel Co (II) metal-organic framework (Co-MOF), namely Co [(NTB) bpy] (NTB = 4,4'4″-tricarboxylic acid triphenylamine, bpy = 4,4 '-bipyridyl), was successfully synthesized with excellent water stability and fluorescence properties. Due to the propeller structure of NTB ligands, a special topological structure of Co-MOF was shown: {24.416.68}{2}4. It was proved that Co-MOF has great stability by soaking in different solvents for two weeks. Remarkably, the fluorescence quenching experiment verified that Co-MOF has excellent fluorescence sensor performance. Trinitrophenol, 2,4-dinitrophenol, and 2-amino-4-nitrotoluene (10-5 M) with LOD of 9.00 × 10-5, 5.40 × 10-5 and 5.07 × 10-6 M can be detected via the process of fluorescence enhancement and quenching. Throughout the investigation, the mechanics of fluorescence quenching was performed. Due to the excellent UV absorption capacity of Co-MOF, it was a promising application to combine low-dimensional nanomaterials with sustainable biomass materials. A hybrid films of Co-MOF and cellulose acetate (CA) was generated. The hybrid films had highly transparency in the visible wavelength range and excellent UV-shielding ability owing to the CA/Co-MOF hybrid films enhanced the UV absorption capacity of Co-MOF.

Activation of sulfite by metal-organic framework-derived cobalt nanoparticles for organic pollutants removal.

Sulfite (SO32-) activation is one of the most potential sulfate-radical-based advanced oxidation processes, and the catalysts with high efficiency and low-cost are greatly desired. In this study, the cobalt nanoparticles embedded in nitrogen-doped graphite layers (Co@NC), were used to activate SO32- for removal of Methyl Orange in aqueous solution. The Co@NC catalysts were synthesized via pyrolysis of Co2+-based metal-organic framework (Co-MOF), where CoO was firstly formed at 400℃ and then partially reduced to Co nanoparticles embedded in carbon layers at 800℃. The Co@NC catalysts were more active than other cobalt-based catalysts such as Co2+, Co3O4 and CoFe2O4, due to the synergistic effect of metallic Co and CoxOy. A series of chain reaction between Co species and dissolved oxygen was established, with the production and transformation of SO3•-, SO52-, and subsequent active radicals SO4•- and HO•. In addition, HCO3- was found to play a key role in the reaction by complexing with Co species on the surface of the catalysts. The results provide a new promising strategy by using the Co@NC catalyst for SO32- oxidation to promote organic pollutants degradation.

Effects of ultrafiltration on Co-Metal Organic Framework/pre-hydrolysis solution carbon materials for supercapacitor energy storage.

Here, a Co-Metal Organic Framework/pre-hydrolysis (Co-MOF/pre-hydrolysis) solution carbon material is prepared by a mild and environmentally-friendly hydrothermal carbonization technique using a pulping pre-hydrolysis solution as the raw material and Co-MOF as the metal dopant. The stable hollow structure provide sufficient space for particle shrinkage and expansion, while the low density and large specific surface area of the long, hairy tentacle structure provide a greater contact area for ions, which shorten the transmission path of electrons and charges. The materials exhibit excellent specific capacitance (400 F/g, 0.5 A/g) and stability (90%, 10,000 cycles). The Change of different concentration ratios in the structures significantly affect the electrochemical performance. The specific surface area of the carbon materials prepared by ultra-filtration increased, but the specific surface area decrease as ultrafiltration concentration increase. The specific capacitance decrease from 336 F/g for C-ZIF-67-1/3 volume ultrafiltration to 258 F/g for C-ZIF-67-1/5 ultrafiltration. The results indicate that energy storage by the carbon materials relied on a synergistic effect between their microporous and mesoporous structures. The micropores provide storage space for the transmission of ions, while the mesopores provide ion transport channels. The separation of large and small molecules after ultrafiltration concentration limit the ion transmission and energy storage of the pores.

An electrochemical aptasensor based on target triggered multiple-channel DNAzymes cycling amplification strategy with PtFe@Co-MOF as signal amplifier.

A novel electrochemical aptasensor for the detection of Aflatoxin B1 (AFB1) was developed for the first time by using the target-triggered multiple-channel deoxyribozymes (DNAzymes) cycling amplified assay with Pt Fe doped NH2-Co-MOF (PtFe@Co-MOF) as a signal amplifier. In the presence of AFB1, a self-assembling cross-over nucleic structure could be triggered by AFB1 via two aptamers' structure switching for strand displacement, resulting in four channels of Mg2+-dependent DNAzyme recycling simultaneously to multiply the detection signals. These DNAzymes cyclically split the substrate sequence to release the PtFe@Co-MOF labeled detection probe (DP), which is subsequently hybridized with the capture probes on the Au-deposited glassy carbon electrode. The fabrication procedure was characterized by differential pulse voltammetry, and the results of the morphological and element composition characteristics methods were analyzed to determine the successful preparation of PtFe@Co-MOF. The limit of detection (LOD) for AFB1 detection was 2 pg mL-1 with a linear range from 5 pg mL-1 to 80 ng mL-1. By comparison, the enhanced detection sensitivity has been found to originate from the efficient shearing of DNAzymes, enhanced peroxidase-like capability, and multiple active sites of PtFe@Co-MOF. Besides, this aptasensor showed high specificity for AFB1 compared with similar mycotoxins and exhibited high accuracy with low experimental cost and easy operation. Furthermore, the unique design of electrochemical aptasensors could provide a promising platform for the onsite determination of AFB1, as well as other targets by replacing the aptamer and other core recognition sequences.

In-Built Fabrication of MOF Assimilated Porous Hollow Carbon from Pre-Hydrolysate for Supercapacitor.

With the fast consumption of traditional fossil fuels and the urgent requirement for a low-carbon economy and sustainable development, supercapacitors are gaining more and more attention as a clean energy storage and conversion device. The research on electrode materials for supercapacitors has become a hot topic nowadays. An electrode material for a supercapacitor, comprising the ZIF-67 in-built carbon-based material, was prepared from a biomass pre-hydrolysate via a hydrothermal process. As a by-product of dissolving slurry, the pre-hydrolysate is rich in carbon, which is an excellent biomass resource. The utilization of pre-hydrolysate to prepare carbon energy materials could realize the high value utilization of pre-hydrolysate and the efficient energy conversion of biomass. Meanwhile, the cobalt-based MOF (such as ZIF-67), as a porous crystalline material, has the advantages of having a regular order, high specific surface area and controllable pore size, as well as good thermal and chemical stability. The addition of ZIF-67 modified the morphology and pore structure of the carbon, and the obtained samples showed outstanding electrochemical performance. One- and two-step synthetic processes generated specimens with a coral-like cross-linked structure and a new type of rough, hollow, dandelion-like structure, respectively, and the pore size was in the range of 2.0-5.0 nm, which is conducive to ion transport and charge transfer. In C2-ZIF-67, the hollow structures could effectively prevent the accumulation of the electrochemical active center, which could provide enough space for the shrinkage and expansion of particles to protect them from the interference of electrolytes and the formation of solid electrolyte interphase film layers. Additionally, the plush tentacle structure with low density and a large specific surface area could expose more active sites and a large electrolyte electrode contact area, and short electron and charge transport paths. Importantly, active, free electrons of small amounts of Co-MOF (1 wt%) could be stored and released through the redox reaction, further improving the electrical conductivity of Carbon-ZIF-67 materials in this work. Consequently, C2-ZIF-67 exhibited superior specific capacitance (400 F g-1, at 0.5 A g-1) and stability (90%, after 10,000 cycles).

Microelectronic structure changes electron utilization: Core-shell structure catalysts with electron library and quantum dots for photocatalytic hydrogen production.

Photocatalysis is facing huge challenges especially the separation and efficient utilization of photocarriers. Herein, we report that a ternary hollow core-shell photocatalyst is synthesized by template and self-assembled method. The experimental results show that the electron separation efficiency and utilization efficiency are significantly improved, not only because the ternary hollow core-shell structure spatially separates the oxidation area MnOx from the reduction area Co-MOF, but also because lots of emergent electrons are stored in Co-MOF as an electronic library, contributing to the formation of surface polarization to support the requirement call from the CoP quantum dots (QDs) as active-sites. It's the first report that the effectively separated electron-rich and electron-poor microelectronic states of the tunable Co-MOF promotes electron utilization by affecting the storage capacity of the electron library promoting photocatalytic hydrogen production. The tests show that Mn@Cd-CoP QDs/MCN (35.31 mmol/h/g), Mn@Cd-CoP QDs/BCN (23.69 mmol/h/g) and Mn@Cd-CoP QDs (11.08 mmol/h/g) have the better hydrogen production performances, which is about 38 times, 26 times and 12 times higher than CdS (0.9244 mmol/h/g), respectively. The pioneering exploration about the ternary hollow core-shell structure bonded with MOFs materials with abundant CoP QDs will open up a new perspective to design high-performance for solar-chemical energy conversion.

Modified montmorillonite synergizes with Co-MOF@PBO fabric to improve the wear resistance of PBO/phenolic resin composites.

Co-MOF (cobased metal-organic frame) nanosheets were developed onto the surface of PBO (poly(p-phenylene benzobisoxazole)) fabric, and OMMT (modified montmorillonite) was incorporated into phenolic resin synergistically to improve the wear resistance of PBO/phenolic resin composites. Co-MOF nanosheets with a large specific surface area exhibited strong interlocking and excellent compatibility between the fabric and resin. In addition, OMMT possessed excellent affinity with phenolic resin and a larger lamellar space, and then polymer chains could be conveniently entangled into interlayers, which further confined the movement of molecular chains caused by friction heat. In addition, a weak interlayer force was conducive to facilitating the formation of a uniform and robust transfer-film on the counterpart. It was demonstrated that the Co-MOF@PBO/OMMT composites presented optimal tribological behavior due to the synergistic effect between interfacial modification and OMMT reinforcement.

Co-MOF-74 based Co3O4/cellulose derivative membrane as dual-functional catalyst for colorimetric detection and degradation of phenol.

Smart nanomaterials that can simultaneously detect and eliminate contaminants in water environment are significant for health protection. To achieve such goal, Co-MOF-74 was in-situ assembled on regenerated cellulose membranes followed by calcination process, thus achieving dual-functional Co3O4/cellulose derivative membrane (Co3O4/CDM) catalyst. The Co3O4 morphology was readily controlled by further recrystallization of the deposited MOF precursor. Combining the high enrichment ability of cellulose membrane and outstanding peroxidase-active of Co3O4, the fast color reaction for phenol was accomplished within 10 min by Co3O4/CDM with the assistance of H2O2 and 4-aminoantipyrine (4-AAP). Moreover, the Co3O4/CDM also portrayed an excellent degradation property for phenol elimination via sulfate radical-advanced oxidation processes (SR-AOPs). The degradation efficiency of phenol reached 93% in 20 min, and the possible mineralization mechanism was proposed based on the XPS and LC-MS analysis. Thus, Co-MOF-74 derived Co3O4/CDM shows excellent properties in aiding the colorimetric detection and degradation of phenol in aqueous solutions.

Fabrication of Vertical-Standing Co-MOF Nanoarrays with 2D Parallelogram-like Morphology for Aqueous Asymmetric Electrochemical Capacitors.

Metal organic frameworks (MOFs) have been considered as one of the most promising electrode materials for electrochemical capacitors due to their large specific surface area and abundant pore structure. Herein, we report a Co-MOF electrode with a vertical-standing 2D parallelogram-like nanoarray structure on a Ni foam substrate via a one-step solvothermal method. The as-prepared Co-MOF on a Ni foam electrode delivered a high area-specific capacitance of 582.0 mC cm-2 at a current density of 2 mA cm-2 and a good performance rate of 350.0 mC cm-2 at 50 mA cm-2. Moreover, an asymmetric electrochemical capacitor (AEC) device (Co-MOF on Ni foam//AC) was assembled by using the as-prepared Co-MOF on a Ni foam as the cathode and a active carbon-coated Ni foam as the anode to achieve a maximum energy density of 0.082 mW cm-2 at a power density of 0.8 mW cm-2, which still maintained 0.065 mW cm-2 at a high power density of 11.94 mW cm-2. Meanwhile, our assembled device exhibited an excellent cycling stability with a capacitance retention of nearly 100% after 1000 cycles. Therefore, this work provides a simple method to prepare MOF-based material for the application of energy storage and conversion.

One-pot construction of highly oriented Co-MOF nanoneedle arrays on Co foam for high-performance supercapacitor.

Highly oriented Co-MOF nanoneedle arrays arein situconstructed on Co foam (Co-MOF@Co) by using a one-pot solvothermal strategy. As-prepared Co-MOF@Co can be directly served as a binder-free electrode for supercapacitor, which exhibits wonderful electrochemical performances, i.e. high specific capacitance (12783.0 mF cm-2or 1164.2 F g-1), exceptional cycling stability (90.5% retention over 10 000 cycles at 250 mA cm-2) with a loading of 10.98 mg cm-2. Meanwhile, an asymmetric supercapacitor of AC//Co-MOF@Co delivers a high ratability (87% retention upon ten-fold current density) and high energy density of 43.4 W h kg-1at the power density of 145.1 W kg-1.