Enzymes are biomolecules with remarkable catalytic properties, which play a critical role in the driving toward green and sustainable methodologies for chemicals manufacturing. In spite of many advantages in enzyme catalysis, it remains fragile entities. These defects limit the widespread application of enzymes in industry. It is a favorable choice to immobilize the enzyme on solid supports to enhance its activity and stability. Metal-organic frameworks (MOFs) are excellent porous materials that possess tunable porosity, desirable functionality, extremely high surface area, and excellent chemical/thermal stability. It has made great achievements in the encapsulation of enzymes in the past few years. In this article, we focus on the recent advances of these composites, especially in the encapsulated strategies and mechanism, and future perspectives are discussed as well

In this study, we report the application of magnetic metal-organic frameworks as a novel adsorbent for fast removal of Pb(II) ions from aqueous solution in view of adsorption isotherms, kinetics, thermodynamics, desorption, and adsorbent regeneration. The adsorbent was characterized by PPMS, XRD, TEM and N₂ adsorption/desorption measurement. The adsorption follows pseudo-second-order kinetics model and fits the Freundlich adsorption model with the adsorption capacity of 612 mg g^–1 for Pb(II) ions. It is a spontaneous and endothermic process controlled by positive entropy change. The used Fe₃O₄/HKUST-1 could be regenerated effectively and recycled at least four times without significant loss of adsorption capacity.

Nowadays, there has been an enormous demand for chemical sensors to detect a variety of analytes for a range of applications, including homeland security guarding, exploration of mineral resources, meteorological observation and telemetry, industrial automation, agricultural fresh preservation, environment monitoring and food quality controlling. Metal-organic frameworks are a new class of porous materials, which are formed by the assembly of metal ions with functional organic ligands. They have attracted great attention in chemical sensing owing to their suitable porosity, specific functional groups, higher quantum yield and tunable luminescent properties. This review summarizes some examples of the application of luminescent metal-organic frameworks for sensing of nitro explosives, metal ions, small molecules, pH value and temperature.

In this paper, we start with a short introduction to the research background of gas adsorption in the metal-organic frameworks (MOFs) field, and then we highlight the gas adsorption sites and behaviors with the aid of various characterization methods, among which we discuss mainly infrared absorption and Raman scattering, as well as X-ray diffraction and neutron diffraction. In addition, we introduce briefly X-ray spectroscopy because they also play a crucial role in understanding MOFs’ gas adsorption. On the other hand, computational simulations, which can reveal underlying adsorption and working mechanism in microscale, are also discussed. Finally, comprehensive kinetic studies are briefly summarized based on these advanced characterization methods.

Removal of mercury contaminants from nature receives a global attention from a biological and environmental standpoint. Recently, metal-organic frameworks (MOFs) show much promises in the adsorptive removal of mercury species. This review summarizes the recent studies on the MOF-based materials for mercury sensing and removal. The design of those materials are listed in five categories—use of unfunctionalized MOFs, linker design of MOFs, modification of MOF system, post-synthetic modification of the frameworks, and development of MOF-based composites. Finally, several key learning points are discussed in the aim of a facilitating new design of MOF-based sensors and adsorbents for mercury.

Metal-organic frameworks (MOFs) are a new class of crystalline porous materials, having wide pores which provide extremely high specific surface areas, larger than those typically observed in more common porous materials like zeolites or activated carbons. This peculiar property combined with the frequent presence of open-metal sites, makes them very promising for a broad range of applications, spacing from gas storage or separation, drug delivery, toxic air removal, chemical detectors, etc. However, the industrialization of MOFs is still facing difficulties because of their low stability to water or even air moisture, a substance difficult to avoid in applications like those mentioned. Another issue concerning MOF industrialization consists in the low bulk density of the micrometric powder grains, which typically constitute such materials. Unfortunately, their low mechanical stability seems to make difficult even to enhance the packaging by simple mechanical compaction. In this review, we will particularly focus on the current state of art involving the MOF HKUST-1, especially on the degradation process involved when this MOF interacts with water molecules. Furthermore, we will show the connection between water and mechanical stability, bringing to attention of a study where solid tablets of HKUST-1 powder have been realized without any loss of crystallinity or porosity because of an accurate study on the effects of different degree of hydration during the tableting phases. In addition, in order to highlight the causes of damages induced in the framework upon interaction with water, a comparison with other two copper carboxylate MOFs will be shown, namely STAM-1 and STAM-17-OEt, which differ from HKUST-1 uniquely for the organic ligands.