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Metal–organic frameworks (MOFs) are significant useful molecular materials as a result of their high surface area and flexible catalytic activities by tuning the metal centers and ligands. MOFs have attracted great attention as efficient nanozymes recently; however, it is still difficult to understand polymetallic MOFs for enzymatic catalysis because of their complicated structure and interactions. Herein, bimetallic NiFe2 MOF octahedra were well prepared and exhibited enhanced peroxidase-like activities. The synergistic effect of Fe and Ni atoms was systematically investigated by electrochemistry, X-ray photoelectron spectrometry, (XPS) and in situ Raman techniques. The electrons tend to transfer from Ni2+ to Fe3+ in NiFe2 MOFs, and the resulting Fe2+ is ready to decompose H2O2 and generate ·OH by a Fenton-like reaction. After integration with glucose oxidase (GOx), which can downgrade the pH value and generate H2O2 by oxidation of glucose, a self-activated cascade reagent is therefore established for efficiently inducing cell death. The changes of cell morphology, DNA, and protein are also successfully recorded during the cell death process by Raman spectroscopy and fluorescence imaging.

Metal−organic frameworks (MOFs) are widely used to mimic enzymes for catalyzing chemical reactions; however, low enzyme activity limit their large-scale application. In this work, gold nanorods/metal−organic frameworks (Au NRs/Fe-MOF) hybrids were successfully synthesized for photo-enhanced peroxidase-like catalysis and surface-enhanced Raman spectroscopy (SERS). The enzyme-like activity of Au NRs/Fe-MOF hybrids was significantly enhanced under localized surface plasmon resonance (LSPR), because the hot electrons produced on Au NRs surface were transferred into Fe-MOF, activating the Fenton reaction by Fe 3+ /Fe 2+ conversion and preventing the recombination of hot electrons and holes. This photo-enhanced enzyme-like catalytic performance was investigated by X-ray photoelectron spectrometry (XPS), electrochemical analysis, activation energy measurement, and in situ Raman spectroscopy. Afterward, Methylene Blue (MB) was chosen to demonstrate the photo-enhanced peroxidase-like performance of Au NRs/Fe-MOFs. The Au NRs/Fe-MOF caused chemical and electromagnetic enhancement of Raman signals and exhibited a great potential for the detection of toxic chemicals and biological molecules. The detection limit of MB concentration is 9.3 × 10 −12 M. In addition, the Au NRs/Fe-MOF hybrids also showed excellent stability and reproducibility for photo-enhanced peroxidase-like catalysis. These results show that nanohybrids have great potential in many fields, such as sensing, cancer therapy, and energy harvesting.

In this study, the effect of pore textural property and surface functionalization in activated carbon (AC) on the competitive adsorption and diffusion of a binary mixture of CO2/CH4 was examined by grand canonical Monte Carlo simulations and equilibrium molecular dynamics. The simulation results indicated that AC with a high surface area exhibited a low CO2/CH4 selectivity, while a high CO2 adsorption capacity was observed. To obtain high CO2 adsorption capacity and high CO2/CH4 selectivity at the same time, surface chemistry (adsorbent–adsorbate interaction) and pore textural property (pore size) were investigated. On this basis, two types of AC were prepared: (I) with different pore sizes, attributed to building ordered pores and (II) with different surface chemistry properties, attributed to modification with different functional groups. The results showed that the effects of surface chemistry properties are factors more important for improving the CO2/CH4 capacity and selectivity.

Synthesis of long chain-branched polypropylene (LCB-PP) by propylene copolymerization with nonconjugated α,ω-diolefin is a steric hindrance-prevailing reaction process which involves in copolymerization not only α,ω-diolefin itself (α-olefin copolymerization) but also polymeric olefin intermediate derived from the first α-olefin copolymerization (ω-olefin copolymerization). This reaction mishap reaches its extreme when Ziegler−Natta catalysts based on MgCl 2supported TiCl 4 (MgCl 2 /TiCl 4 catalysts) are considered as catalyst, which produce active sites that are highly sensitive to olefin monomer's steric bulkiness. A proposition is put forward that such a steric difficulty may be overcome by functionalization of α,ω-diolefin with Lewis base functionality, which would usher in an extra electronic pulling effect to help with olefin coordination to the active center in both the α,ω-diolefin's monomeric α-olefin and the polymeric ω-olefin polymerization steps. Three model compounds, including di-n-hexyldiethoxysilane, di-5hexenyldiethoxysilane, and di-5-hexenyldimethylsilane, were synthesized and used to attest to the validity of the hypothesis. The experimental results evidently proved that the Lewis base functionality enabled the functionalized α,ω-diolefin to establish dynamic electron-donating interactions with MgCl 2 /TiCl 4 catalysts, making it far more effective in prompting LCB in copolymerization with propylene due to greatly enhanced polymerization reactivity of both its monomeric α-olefin and polymeric ω-olefin in their respective polymerization steps. The electronic promotion effect was found to be so robust that it could not be offset by reducing the initial α,ω-diolefin molecular steric hindrance. This approach is promising to solve the real issue of synthesizing LCB-PP by Ziegler−Natta catalyst.

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Construction of localized drug‐eluting systems with synergistic chemothermal tumor‐killing abilities is promising for biomedical implants directly contacting with tumor tissues. In this study, an intelligent and biocompatible drug‐loading platform, based on a gold nanorods‐modified butyrate‐inserted NiTi‐layered double hydroxides film (Au@LDH/B), is prepared on the surface of nitinol alloy. The prepared films function as drug‐loading “sponges,” which pump butyrate out under near‐infrared (NIR) irradiation and resorb drugs in water when the NIR laser is shut off. The stimuli‐responsive release of butyrate is verified to be related with the NIR‐triggered crystal phase transformation of Au@LDH/B. In vitro and in vivo studies reveal that the prepared films possess excellent biosafety and high efficiency in synergistic thermochemo tumor therapy, showing a promising application in the construction of localized stimuli‐responsive drug‐delivery systems.

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