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Reported herein is a highly stable rod-packing Sc-MOF with Lewis basic bare N sites and two types of open channels demonstrating a superior CO2 storage capacity, a remarkable separation ability for CO2 mixtures, and prominent catalytic CO2 cycloaddition.

The development of paraffin-selective adsorbents is desirable but extremely challenging because adsorbents usually prefer olefin over paraffin. Herein, a new pore-window-partition strategy is proposed for the rational design of highly efficient paraffin-preferred metal-organic framework (MOF) adsorbents. The power of this strategy is demonstrated by stepwise installations of linear bidentate N-donor linkers into a prototype MOF (SNNU-201) to produce a series of partitional MOF adsorbents (SNNU-202-204). With continuous pore-window partitions from SNNU-201 to SNNU-204, the isosteric heat of adsorption can be tuned from -34.4 to -19.4 kJ mol

MIL-53-Al/Ga/In fluorescent probes are constructed by adjusting the influence of metal centers on the ESIPT process in MOFs and experimental results indicate that the weaker the metal polarization, the stronger the sensor sensitivity.

Ultra-stable Zn-organic frameworks with controllable inverse adsorption separation of C2H2/CO2 demonstrate extraordinary CO2-preferred selectivity and a remarkable productivity of C2H2 with an extra-high purity of more than 99.9% from the CO2/C2H2 (1/99) mixture.

A series of ultra-microporous copper(i)-1,2,4-triazolate frameworks exhibit moderate C2H2 uptake capacity, high C2H2/CO2 and C2H2/C2H4 separation ability, and remarkably lower isosteric heat of C2H2 adsorption regulated by halogen hydrogen bond.

A two-dimensional (2D) MOFs transformation strategy was introduced to synthesize FeNi layered double hydroxides (FeNi LDHs) in NaBH4 solution, which show excellent OER catalytic activity in alkaline media.

MOF-derived porous materials Co3O4 and Co/C with hierarchical structure (MHCo3O4 & Co/C) were prepared by the self-sacrificial template strategy, and the surface of such materials were functionally modified with 'polydopamine (PDA)' bionic membrane for entrapping horseradate peroxidase (HRP) in this work. MHCo3O4 was prepared in air atmosphere and Co/C was prepared in nitrogen atmosphere based on thermolysis of Co-MOF. The HRP@PDA@MHCo3O4 and HRP@PDA@Co/C could remain 96.8% and 93.7% catalytic activity compared to the free HRP, and exhibited better thermal stability and reusability. After 1 h incubation at 70 °C, the HRP@PDA@MHCo3O4 and HRP@PDA@Co/C retained 84.8% and 70.8% of the initial activity compared with less than 20% retained by free HRP; After 10 cycles, the HRP@PDA@MHCo3O4 and HRP@PDA@Co/C retained 92.4% and 85.4% of the initial activity. Moreover, the HRP@PDA@MHCo3O4 & Co/C exhibited extremely catalytic degradation efficient for 2,4-dichlorophenol in simulated wastewater, and 2 mmol·L-1 of 2,4-dichlorophenol was completely degraded within 15 min. The superior properties of HRP@PDA@MHCo3O4 & Co/C was researched by the analyses of kinetics and thermodynamics. The results suggested that the mass transfer resistance of the substrates were lower than that of the bulk solution, for the reason that the substrates were originally enriched on the hierarchical porous carrier close to enzyme. The specificity and binding affinity of the enzymatic reactors to substrates were enhanced by the functionalized 'PDA' bionic membrane on the carrier surface, compared with free enzyme in bulk buffer.

Simple, fast, and sensitive detection of trace water in organic solvents is an urgent requirement for chemical industries. Herein, combining the unusual excited-state intramolecular proton transfer (ESIPT) mechanism with the effective strategy of pore space partition, for the first time, we construct a powerful fluorescent metal-organic framework (SNNU-301) probe with excellent water stability. The SNNU-301 probe shows a remarkable performance for turn-on ESIPT-based fluorescence response to water in nine common organic solvents, exhibiting wide linear ranges, low limit of detection values, and ultrafast response, especially in dimethyl sulfoxide (0-5.2%; 0.011%, v/v; 110 s). The typical ESIPT-sensitive linker 2,5-dihydroxyterephthalate (DHBDC) imparts it with discriminative detection properties via enol-keto tautomerism, and light-responsive triangular tri(pyridin-4-yl)-amine (TPA) realizes pore space partition. The theoretical calculation gives an in-depth explanation about the proton transfer mechanism. Comparative experiments and GCMC simulation provide evidence that the synergy of the ESIPT process and TPA of the framework further boosts its performance effectively. Definitely, this work not only offers a promising candidate with fast detection speed, high sensitivity, excellent universality, and visual observation for the determination of water in organic solvents but also provides valuable guidance for the design of high-performance fluorescent probes.

Metal–organic frameworks (MOFs) exhibit great potential for lithium-sulfur (Li–S) batteries because of their unique characteristics such as the high surface area, the precise structure, and the tunable porous environment. However, their low binding energy with sulfur and poor absorbability of polysulfides leads to the “shuttle effect,” reducing the stability of MOFs. With strong bonding ability to sulfur, indium-based MOFs, in which the indium (In) shows the Lewis acid character, can form the stable chemical bonds of In-S. Based on it, we used the indium-based MOF-CPM-200 as a carrier, combined with the conductive multi-walled carbon nanotubes (CNT) and sulfur to construct the composite cathode material of CPM-200/CNT@S. The unique composite structure for cathode materials of Li–S batteries can inhibit the “shuttle effect” and enhance conductivity. The initial discharge capacity of the CPM-200/CNT@S can reach as high as 1400 mAh∙g−1 and maintain a capacity of about 840 mAh∙g−1 after 100 charge–discharge cycles at 0.1 C, the coulombic efficiency approaches 100%. This work offers a new strategy for constructing the MOFs-based cathode materials for Li–S batteries with high performance.

We report a new sensing mechanism based on an indium-dihydroxyterephthalic acid metal-organic framework (MOF, SNNU-153), in which the spatially fitted analyte-MOF hydrogen-bond (H-bond) formation provides selective recognition while the analyte-H-bond assisted excited-state intramolecular proton transfer (ESIPT) and the resulting ratiometric emission act as a superior signal transducer with ultrafast response. The synergy of ESIPT signal transduction and confined MOF pore enables the SNNU-153 sensor selectively sensing hydrazine even among nitrogen-containing hydride analogs such as NH3, NH2OH, and (Me)2NNH2. The key of H-bond and associated ESIPT was further counter evidenced by an indium-2,5-dimethoxyterephthalic acid MOF (SNNU-152), where the hydroxyl protons were removed by methylation, showing near inertness to N2H4. The new molecular recognition concept thus makes SNNU-153 a powerful N2H4 sensor, which should be far-reaching to other sensing elements.

In this paper, the solid–liquid equilibrium of N-methylpyrrolidone (NMP) + MCl (M = Na, K, Rb, and Cs) + H2O ternary systems was investigated at three temperatures (T = 288.2, 298.2, and 308.2 K). ...

Metal-azolate-carboxylate frameworks have great potential for gas adsorption applications because azole ligands with a small size easily construct small pore MOFs with bare −N(H) donor sites. Howev...

Enzymes are efficient catalysts offering much more competitive processes than conventional chemical reactions. However, the lack of stability and reusability is a key issue on the use of enzymes in industrial applications. These drawbacks can generally be overcome by immobilization of the enzyme on a solid support. In this work, a Fe3O4/Fe-MOF core–shell with hierarchical pore sizes was prepared by growing Fe-MOF around Fe3O4 nanoparticles via solvothermal synthesis. Fe3O4/Fe-MOF integrates magnetic characteristics and hierarchical porous structure for supporting chloroperoxidase (CPO) or horseradish peroxidase (HRP). Immobilized CPO/HRP exhibited significantly enhanced stability against temperature stress and facilitated reuse. For example, HRP-Fe3O4/Fe-MOF can retain 94.1% activity after 10 reuses. Moreover, CPO/HRP-Fe3O4/Fe-MOFs were very efficient in the degradation of organic toxins, isoproturon or 2,4-dichlorophenol in simulated wastewater with a complete degradation within 15 min. The excellent performance of CPO/HRP-Fe3O4/Fe-MOF was investigated by kinetic and thermodynamic analysis. The results indicated that the diffusion resistance of substrates was reduced compared with that in a bulk solution because they were initially concentrated close to enzymes on the hierarchically porous support. The specificity and binding affinity of the immobilized enzymes are enhanced compared with the free enzymes.

Holey CoOOH nanosheets (CoOOH HNSs) are easily synthesized by a successive coordination–oxidation–hydrolysis strategy. The CoOOH HNSs possess a large surface area, numerous pores, and substantial edge atoms with excellent electroactivity towards the oxygen evolution reaction in alkaline solution. The overpotential of 305 mV at 10 mA cm−2 for the CoOOH HNSs exceeds that of most monometallic Co-based electrocatalysts.

By employing a tetraphenylethylene (TPE)-based tetracarboxylate linker, tetrakis(4-carboxyphenyl)ethylene (H4TCPE), we herein constructed a novel luminescent Mn-MOF based on a rare [Mn4(μ3-OH)2] cluster (SQNU-55). Interestingly, the TPE-based SQNU-55 not only provides a good material for the blue LED device, but also has a better luminescent molecular thermometer for low-temperature detection.

Both methane (CH4) and acetylene (C2H2) are important energy source and raw chemicals in many industrial processes. The development of an energy-efficient and environmentally friendly separation and purification strategy for CH4 and C2H2 is necessary. Ultramicroporous metal-organic framework (MOF) materials have shown great success in the separation and purification of small-molecule gases. Herein, the synergy effect of tritopic polytetrazolate and ditopic terephthalate ligands successfully generates a series of isoreticular ultramicroporous cadmium tetrazolate-carboxylate MOF materials (SNNU-13-16) with excellent CH4 and C2H2 purification performance. Except for the uncoordinated tetrazolate N atoms serving as Lewis base sites, the pore size and pore surface of MOFs are systematically engineered by regulating dicarboxylic acid ligands varying from OH-BDC (SNNU-13) to Br-BDC (SNNU-14) to NH2-BDC (SNNU-15) to 1,4-NDC (SNNU-16). Benefiting from the ultramicroporous character (3.8-5.9 A), rich Lewis base N sites, and tunable pore environments, all of these ultramicroporous MOFs exhibit a prominent separation capacity for carbon dioxide (CO2) or C2 hydrocarbons from CH4 and C2H2. Remarkably, SNNU-16 built by 1,4-NDC shows the highest ideal adsorbed solution theory CO2/CH4, ethylene (C2H4)/CH4, and C2H2/CH4 separation selectivity values, which are higher than those of most famous MOFs with or without open metal sites. Dynamic breakthrough experiments show that SNNU-16 can also efficiently separate the C2H2/CO2 mixtures with a gas flow rate of 4 mL min-1 under 1 bar and 298 K. The breakthrough time (18 min g-1) surpasses most best-gas-separation MOFs and nearly all other metal azolate-carboxylate MOF materials under the same conditions. The above prominently CH4 and C2H2 purification abilities of SNNU-13-16 materials were further confirmed by the Grand Canonical Monte Carlo (GCMC) simulations.

High storage capacity, high separation selectivity, and high structure stability are essential for an idea gas adsorbent. However, it is not easy to achieve all three at the same time, even for the promising metal-organic framework (MOF) adsorbents. We demonstrate herein that robust [Sc

The construction of nanocage-based metal-organic frameworks (MOFs) with both open metal sties (OMSs) and optimal pore spaces may offer a powerful route for high-performance gas storage and purifica...

The construction of superstable metal-organic frameworks (MOFs) for selective gas uptake is urgently demanded but remains a great challenge. Herein, a unique bifunctional deformed [Ga3O(COO)6] inorganic secondary building unit (SBU) generated from the desymmetrical evolution of typical triangular prismatic trinuclear cluster was first introduced, which was extended by an isosceles triangular organic linker to produce a robust Ga-MOF (SNNU-63). Remarkably, SNNU-63 can stabilize in water at 25 °C for 96 h and at 80 °C for more than 24 h, which surpasses nearly all other Ga-MOFs. The combined effects of open metal sites and hydrophobic pore environment provided by deformed [Ga3O] SBUs render SNNU-63 with high C2H2 storage capacity and efficient C2H2 and natural gas purification performance. The ideal adsorbed solution theory calculation, column breakthrough tests, and grand canonical Monte Carlo simulations demonstrate that SNNU-63 is a potential material for addressing the challenge of C2H2/CO2 and C2H2/CH4 mixture separation under ambient conditions.

The separation of a mixture of C2H2 and CO2 is a great challenge due to their similar molecular sizes and shapes. Al-based metal-organic frameworks (Al-MOFs) have great promise for gas separation applications due to their light weight, high stability, and low cost. However, the cultivation of suitable Al-MOF single crystals is extremely difficult and has limited their explorations up to now. Since In, Ga, and Al are all 3p-block metal elements, a systematic application of the periodic law to investigate 3p-MOFs will undoubtedly help in the understanding and development of worthy Al-MOF materials. Herein, we report the design of a robust 3p metal-organic framework platform (SNNU-150) and the systematic regulation of C2H2/CO2 separation by open 3p-block metal sites. X-ray single-crystal diffraction analysis reveals that SNNU-150 is a 3,6-connected 3D framework consisting of [M3O(COO)6] trinuclear secondary building units (SBUs) and tritopic nitrilotribenzoate (NTB) linkers. Small {[M3O(COO)6]4(NTB)6} tetrahedral cages and extra-large {[M3O(COO)6]10(NTB)14} polyhedral cages connect with each other to generate a hierarchically porous architecture. These 3p-MOFs present very high water, thermal, and chemical stability, especially for SNNU-150-Al, which can maintain its framework at 85 °C in water for 24 h and in a room-temperature environment for more than 30 days. IAST calculations, breakthrough experiments, and GCMC simulations all show that SNNU-150 MOFs have top-level C2H2/CO2 separation performance and follow the order Al-MOF > Ga-MOF > In-MOF.

Metal-organic frameworks (MOFs) with large surface area, abundant coordination metal centers and tunable structures are regarded as promising electrocatalysts for the water splitting reaction. However, the less accessible active sites and poor stability of MOFs hinder their potential practical applications. Hierarchical double-layer hydroxide (LDH)/MOF electrocatalysts that combine the advantages of two materials are expected to overcome these drawbacks. Herein, we develop a simple and universal strategy, in situ pseudomorphic transformation, to construct hierarchical LDH/MOF electrocatalysts. Accordingly, ultra-thin Fe-Ni LDH nanosheets are in situ produced in the heterometallic MOF during the transformation process. Profiting from the abundant metal sites and the extended electron transport channel from the inserted ultra-thin LDH arrays, the hierarchical Fe-Ni LDH/MOFs exhibit striking electrochemical activities for the oxygen evolution reaction (OER). In particular, the as-synthesized Fe-Ni LDH/MOF-b2 delivers the best OER performance, exhibiting an ultralow overpotential (255 mV at 10 mA cm-2), minimum Tafel slope (24 mV dec-1) and outstanding cycling durability. Meanwhile, the evolution process of the hierarchical Fe-Ni LDH/MOF has been monitored with the controllable in situ semi-transformation strategy. This also provides an opportunity to decipher the original active species for the OER process. Mechanism analysis indicates that the bimetallic MOF and bimetallic LDH are both active species, and the excellent OER performance of hierarchical Fe-Ni LDH/MOF could be attributed to the effect of "a whole greater than the sum of the parts".

A fluorescent heterometallic Zn/Ca-MOF sensor, named {[(CH3)2NH2]4[Ca2Zn4(L)4]·4DMF}n (1), has been designed based on a flexible ligand ((5,5′-(propanen-1,3-diyl)-bis(oxy)diisophthalic acid (H4L))) under solvothermal conditions. Compound 1 features a novel (4,8)-connected 3D architecture with the linear trinuclear cluster [CaZn2(COO)8] bridged by eight carboxylate groups from different organic ligands. The introduction of Ca2+ into the Zn-MOF effectively improves the thermal and water stability of the heterometallic Zn/Ca-MOF, which encouraged us to evaluate its fluorescence sensing performance. Consequently, compound 1 exhibits highly selective sensing of Fe3+ and Cr2O72− through a luminescence quenching mechanism. The corresponding quenching coefficient (Ksv) values are 4.36 × 103 M−1 for Fe3+ and 1.15 × 103 M−1 for Cr2O72−. The detection limits are estimated to be 18.8 μM for Fe3+ and 29.1 μM for Cr2O72−, which are lower than most reported sensors. Furthermore, the DFT theoretical calculation simulates the modified channel A of alkoxy groups as recognition sites to explain its recognition mechanism for Fe3+.

It is well-known that the formation of ferroalloy with the addition of the second or third metal during the steel-making process usually can improve the performance of the iron. Inspired by ferroalloy materials, it is speculated that the pore environment, framework charge, and catalytic properties of metal-organic frameworks (MOFs) could be optimized dramatically via the introduction of ferroalloy-like inorganic building blocks. However, different to ferroalloy, the accurate integration of different metals into one MOF platform is still challenging. Herein, taking advantages of the good compatibility for metals in trigonal prismatic trinuclear cluster, a series of Fe-based alloy-like [M3O(O2C)6] motifs (M3 = Fe3, Fe1.5Ni1.5, Fe1.5Co1.5, Fe1.5Ti1.5, FeCoNi, and FeTiCo) are successfully generated, which further lead to a robust Fe-MOF material family (SNNU-5s). These multicomponent MOFs not only provide a good chance to explore the impact of pore environment on gas adsorption/separation but also offer an opportunity to the efficient electrocatalytic reaction directly. Accordingly, compared with the SNNU-5-Fe parent structure, the pore characters of heterometallic SNNU-5 MOFs are clearly regulated by the type of alloy-like building blocks. SNNU-5-FeTi displays more superior gas separation performance for CO2/CH4, C2H2/CH4, C2H4/CH4, and C2H2/CO2 gas mixtures. What is more, benefited from the multimetallic active sites and their catalytic synergy, FeCoNi-ternary alloy-like cluster-based SNNU-5 MOF material exhibits an exceptional oxygen evolution reaction activity in aqueous solution at pH = 13, which delivers a low overpotential (ηj=10 = 317 mV), a fast reaction kinetics (Tafel slope = 37 mV dec-1), and excellent catalytic stability. This facile multialloy-like building block strategy holds promise to accurately design and improve the performance of MOFs, as well as open an avenue to understand the related mechanisms.

Evaluating the effect of ligand substitution on metal ions and/or clusters during the MOF growth process is conducive to rational design of isoreticular MOFs with improved performance. Through topo...

Acetylene (C2H2) purification is of great importance for many chemical synthesis and processes. Metal-organic frameworks (MOFs) are widely used for gas adsorption and separation due to their variable structure and porosity. However, the exploitation of ideal MOF adsorbents for C2H2 keeps a challenging task. Herein, a combination of open metal sites (OMSs) and Lewis basic sites (LBSs) in robust MOFs is demonstrated to effectively promote the C2H2 purification performance. Accordingly, SNNU-37(Fe/Sc), two isostructural MOFs constituted by [Fe3O(COO)6] or [Sc3O(COO)6] trinuclear clusters and amide-functionalized tricarboxylate linkers, were designed with extra-stable 3,6-connected new architectures. Derived from the coexistence of high-density OMSs and LBSs, the C2H2 adsorption amounts of SNNU-37(Fe/Sc) are much higher than those values for C2H4 and CO2. Theoretical IAST selectivity values of SNNU-37(Fe) are 2.4 for C2H2/C2H4 (50/50, v/v) and 9.9 for C2H2/CO2 (50/50, v/v) at 298 K and 1 bar, indicating an excellent C2H2 separation ability. Experimental breakthrough curves also revealed that SNNU-37(Fe) could effectively separate C2H2/C2H4 and C2H2/CO2 under ambient conditions. GCMC simulations further indicate that open Fe or Sc sites and amide groups mainly contribute to stronger adsorption sites for C2H2 molecules.

By employing a tetraphenylethylene (TPE)-based tetracarboxylate linker, tetrakis(4-carboxyphenyl)ethylene (H

High-quality CoP nanorings (CoP NRs) are easily achieved using a phosphorating treatment of CoOOH nanorings, and reveal high activity towards the hydrogen evolution reaction and the nitrate electrocatalytic reduction reaction due to substantial coordinately unsaturated active sites, a high surface area, and available mass transfer pathways. Consequently, the CoP NRs can achieve a faradaic efficiency of 97.1% towards NO3−-to-NH3 conversion and provide an NH3 yield of 30.1 mg h−1 mg−1cat at a −0.5 V potential.

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Four cupric cluster based magnetic coordination polymers Cu8O(tta)12(ClO4)2⋅2H2O (1), [Cu5(tta)9]Cl (2), Cu3(OH)2Cl (tta)3 (3) and Cu3(tta)4Cl2 (4) (Htta = 1-H-tetrazole) have been prepared by the same starting materials of cupric chloride and tetrazole, with the only difference of reaction temperature and pH value tuned by inorganic perchloric acid, among which complexes 2 and 3 are initially reported. Notoriously, high temperature can promote the reducing tendency of Cu(II)-to-Cu(I) in Cu/tetrazole system, whereas reducing tendency was prohibited by pH value control using perchloric acid in this work to generate cupric tetrazolate coordination polymers. Furthermore, different cupric cluster secondary building units (SBUs) such as planar Cu4O, trigonal prism-like Cu8, linear Cu3(OH)2 and Cu3Cl2 as well as the overall framework topologies such as bcu, asc and bct were observed. The bonding nature of chloride shows regular variation from free anion, dative Cu⋯Cl bond and normal Cu–Cl coordination bond due to Jahn-Teller effect of Cu(II) ions.

The Solubility, density and refractive index of the formamide(FA)/N-methylformamide(NMF)/N,N-dimethylformamide(DMF) + rubidim bromide/cesium bromide+ water ternary systems were determined at (283.15, 298.15 and 313.15) K. The solubility of the RbBr and CsBr decrease significantly when adding amides into the aqueous solution. The variation trend of density is consistent with solubility, and the change of the refractive index is different. The isothermal experimental solubility was correlated by the NRTL model and the UNIQUAC model. The isothermal solubility, density and refractive index of the ternary systems were fitted by the four parameter equation. Moreover, the mean activity coefficients of the FA/NMF/DMF + RbBr/CsBr + H2O systems at experimental temperatures were obtained through the UNIQUAC model. Besides, to investigate the temperature effect on the solid-liquid equilibrium, the multiple temperatures solubility was fitted by the modified Apelbl at equation and the λh equation.

A multitude of industrial processes are catalyzed by two or more enzymes working together in a cascade way. However, designing efficient enzymatic cascade reactions is still a challenge. In this work, a TiO2 thin film with mesoporous pores was prepared and used as carrier for co-immobilization of chloroperoxidase (CPO) and glucose peroxidase (GOx). By adjusting the dosage of hexadecyltrimethylammonium bromide (CTAB) and the ratio of the two enzymes, CPO and GOx were well distributed and positional orientated to their own appropriate pores to form an ordered “occupation” based on a “feet in right shoes” effect. Moreover, when the pore size was controlled around 12 nm, the enzymes aggregation was inhibited so as to avoid the decrease of activity of enzyme; The catalytic performance of TiO2–GOx and CPO composites was evaluated by the application of decolorization of Orange G dye in a cascaded manner. The oxidant H2O2 needed by CPO is generated in situ through glucose oxidation by GOx. Upon co-immobilization of CPO and GOx on the same carrier, a large increase in the initial catalytic efficiency was detected when compared to an equimolar mixture of the free enzymes, which was four times greater. Moreover, the affinity of the enzyme toward substrate binding was improved according to the kinetic assay. The thermal stability of TiO2–GOx and CPO composites were greatly improved than free enzymes. The TiO2–GOx and CPO composites can be easily separated from the reaction media which facilitate its recycle use.

The concept of high-performance excited-state intramolecular proton transfer (ESIPT)-based fluorescent metal–organic framework (MOF) probes for Al3+ is proposed in this work. By regulating the hydroxyl groups on the organic linker step by step, new fluorescent magnesium–organic framework (Mg–MOF) probes for Al3+ ions were established based on the ESIPT fluorescence mechanism. It is observed for the first time that the number of intramolecular hydrogen bonds between adjacent hydroxyl and carboxyl groups can effectively adjust the ESIPT process and lead to tunable fluorescence sensing performance. Together with the well-designed porous and anionic framework, the Mg–TPP–DHBDC probe decorating with a pair of intramolecular hydrogen bonds exhibits extra-high quantitative fluorescence response to Al3+ through an unusual turn-off (0–1.2 μM) and turn-on (4.2–15 μM) luminescence sensing mechanism. Notably, the 28 nM limit of detection value represents the lowest record among all reported MOF-based Al3+ fluorescent...

Although chloroperoxidase (CPO) has long been recognized as a powerful and versatile catalyst, its applications have been thwarted by the difficulty in regenerating the active enzyme and substrate (peroxide) induced protein inactivation. In this paper, we describe the fabrication and characterization of chloroperoxidase (CPO) and glucose oxidase (GOx) on the surface of MGO. The performance of the immobilized CPO was considerably enhanced by coupling with GOx that provided the required H2O2 in situ through glucose oxidation. The activity of MGO-GOx-CPO (96.6%) towards the decolorization of orange G was much superior to that of MGO-GOx+MGO-CPO (86.2%), probably as a result of reduced mass transfer resistance between CPO and H2O2 generated from GOx molecules. Interestingly, MGO-GOx-CPO reached its peak activity (95.2%) when temperature was maintained between 42 °C and 50 °C compared to the optimal temperature of 35 °C for the free enzyme, possibly due to dispersion of the otherwise stacked MGO below 42 °C. Finally, MGO-GOx-CPO can be conveniently reused for its ease of recovery in the presence of an external magnetic field, with ∼38.5% activity remained after 6 cycles of applications. This work demonstrates the feasibility of co-immobilizing CPO and GOx onto MGO and the potential of MGO-GOx-CPO in environmental applications.

In this paper, the phase behavior of the systems composed of [Cnmim]Cl/Br (n = 2, 4, 6, 8), Rb2SO4/Cs2SO4 and H2O was investigated at 298.2 K and 308.2 K. Some systems were solid – liquid equilibrium and some were liquid – liquid equilibrium because of the effect of the inorganic salts and the cation and anion of the ionic liquids. For solid – liquid equilibrium systems, the solubility, density and refractive index of the saturated solution were determined. For liquid – liquid equilibrium systems, the binodal curves were measured. The experimental solubility, density and refractive index were fitted using an empirical equation. The binodal curves data of liquid – liquid equilibrium systems were correlated using Merchuk equation. Moreover, the effect of inorganic salts, ionic liquids, and temperature on the phase behavior of the studied systems was discussed in detail.