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Monoethylene glycol (MEG) and 1,2-propylene glycol (PG) are important raw materials for the manufacture of polyester resins, antifreezes, cosmetics, medicines, and other products. [1] The total global demand for MEG has been estimated to be over 19 million metric tons per year.[2] The production of MEG in industry predominantly involves the liquid-phase hydration of ethylene oxide (EO), whereby a large excess of water (20-25 mol of water/mol of EO) is required for the high conversion of EO and high selectivity for MEG. The concentration of MEG in the final aqueous solution is only approximately 10 wt %, and huge energy is consumed for the distillation of the product from the aqueous solution. As a result, epoxide hydration is one of the most cost-and energy-intensive processes in the chemical industry.Possible catalytic hydration processes have been extensively investigated for the environmentally friendly production of MEG at a low energy cost. Various types of catalysts, including liquid and solid acids or bases, have been explored, such as sulfuric acid, [3] the salts of some acids, [4] cyclic amines, [5] cation-and anion-exchange resins, [6] quaternary phosphonium halides, [7] polymeric organosilane ammonium salts, [8] macrocyclic chelating compounds, [9] and supported metal oxides.[10] However, a high H 2 O/EO molar ratio (i.e. > 10) is still required for high MEG selectivity. The MEG selectivity is very low at low H 2 O/EO molar ratios owing to the formation of diethylene glycol (DEG) and triethylene glycol (TEG) by the self-condensation of MEG, which is readily catalyzed by acid and base catalysts. Moreover, the inherent corrosion and environmental problems associated with the liquid acids/bases limit their application in industry. The development of an efficient and environmentally benign process for the hydration of epoxides with an H 2 O/epoxide molar ratio approaching the stoichiometric value of the chemical reaction is still a huge challenge.In this study, we developed a solid catalyst that is different from the conventional liquid/solid acid or base catalysts for the hydration of epoxides. We constructed the solid catalyst by encapsulating the molecular catalyst [Co III (salen)], with a salen ligand derived from 3,5-di-tert-butylsalicyclaldehyde and trans-1,2-diaminocyclohexane, [11] in the nanocage of the mesoporous silica FDU-12. This catalyst exhibits high activity and selectivity in the hydration of epoxides under mild reaction conditions. Furthermore, the H 2 O/epoxide molar ratio can be decreased to as low as 2:1 while maintaining the conversion of EO above 98 % and the selectivity for MEG above 98 %. This novel catalytic approach has great potential for the green and energy-saving hydration of epoxides, as well as many other conventional chemical reaction processes in industry.The solid catalyst (denoted as FDU-12-[Co III

The combination of P-POF-Zn and thermal-responsive ionic liquid [CPeDMAPy]Br could efficiently catalyze the cycloaddition reaction of CO2 with epoxides with a stable recovery.

Direct conversion of flue gas and epoxides to cyclocarbonates has been shown, using a 2,2-bipyridine Zn(ii) based hierarchical meso/microporous polymer as a catalyst. Mesopores facilitate reactant diffusion, while micropores enhance CO2 enrichment.

An IL-in-oil Pickering emulsion prepared with Rh-sulfo-xantphos as the catalyst and dendritic mesoporous silica nanospheres as the stabilizer could efficiently catalyze the hydroformylation of 1-dodecene to afford TOF as high as 413 h−1.

Developing solid catalysts with multiple active sites working cooperatively is desirable for efficient chemical transformations. However, most solid catalysts are rigid and impede the cooperation between their spatially isolated active sites. Two flexible porous organic frameworks (POFs) with integrated Co(salen) as active sites have been successfully synthesized for mimicking the cooperative modes of enzymes. The POFs exhibit second-order rate dependence on Co(salen) concentration in the network and afford much higher TOF (3300 versus 2670 h ) than the homogeneous counterpart in the hydration of propylene epoxide. POFs with a flexible network thus not only facilitate but also enhance the cooperation of nearby Co(salen). Moreover, POFs could catalyze oversized substrates, have a wide substrate scope, and exhibit high stability.

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Non-layered 2D ZnSb nanoplates are successfully synthesized to fabricate infrared polarized photodetectors, exhibiting, high responsivity, fast photoresponse speed, great stability, high anisotropic conductivity and linear polarization sensitivity.