Separation is an important industrial step with critical roles in the chemical, petrochemical, pharmaceutical, and nuclear industries, as well as in many other fields. Although much progress has been made, the development of better separation technologies, especially through the discovery of high-performance separation materials, continues to attract increasing interest due to concerns over factors such as efficiency, health and environmental impacts, and the cost of existing methods. Metal-organic frameworks (MOFs), a rapidly expanding family of crystalline porous materials, have shown great promise to address various separation challenges due to their well-defined pore size and unprecedented tunability in both composition and pore geometry. In the past decade, extensive research is performed on applications of MOF materials, including separation and capture of many gases and vapors, and liquid-phase separation involving both liquid mixtures and solutions. MOFs also bring new opportunities in enantioselective separation and are amenable to morphological control such as fabrication of membranes for enhanced separation outcomes. Here, some of the latest progress in the applications of MOFs for several key separation issues, with emphasis on newly synthesized MOF materials and the impact of their compositional and structural features on separation properties, are reviewed and highlighted.

Crystalline semiconducting sulfide and selenide zeolite analogs were synthesized that possess four-connected, three-dimensional tetrahedral networks built from tetravalent (M4+ = Ge4+ or Sn4+, where M = meta) and trivalent (M3+ = Ga3+ or In3+) cations. Microporous materials were obtained in all four combinations of M4+ and M3+, and some of them were thermally stable up to at least 380 degrees C. These materials exhibit framework topologies with pore size ranging from 12 to 24 tetrahedral atoms, high surface area, high framework charge density and ion exchange capacity, and tunable electronic and optical properties.

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In many areas of chemistry the synthesis of chiral compounds is a target of increasing importance. They play a vital role in biological function and in many areas of society and science, including biology, medicine, biotechnology, chemistry and agriculture. Many pharmaceutical molecules, like their biological targets, are chiral and it is therefore easy to understand the growing demand for efficient methods of producing enantiomerically pure compounds. This is equally true for the preparation of chiral solids, which have potential applications in asymmetric catalysis, chiral separations and the like. In this Review we will consider recent progress and future potential in the development of methods for the preparation of chirally pure solids, in particular where the building blocks of the structure are achiral themselves. We will discuss strategies for the synthesis of both inorganic (for example, zeolites) and inorganic-organic hybrid (for example, metal organic framework) chiral porous solids.

One of the most exciting recent developments concerning molecular architectures is the emerging field of crystalline chalcogenide superlattices that bridges two traditional but distinct areas of research: chalcogenide clusters and porous materials. By combining synthetic and structural concepts in these two areas, many crystalline solids containing spatially organized chalcogenide clusters have been created that exhibit varied properties ranging from microporosity, fast ion conductivity, and photoluminescence to narrow and tunable electronic band gaps. The potential applications of these materials extend beyond traditional areas such as acid catalysis or adsorption-based separation to include shape- or size-selective photocatalysis, solid-state ionics, and electrochemistry.