An iron-based metal-organic framework, MIL-101(Fe), promotes photocatalytic water oxidation to produce oxygen from aqueous silver nitrate solution under visible-light irradiation. The finely dispersed iron-oxo clusters embedded as nodes of the porous framework would contribute importantly to the efficient promotion of the reaction as compared to bulk hematite (α-Fe2O3).

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The present article describes the development of a periodic mesoporous organosilica (PMO)-based bifunctional catalyst that includes both oxidative and base catalytic activities. Periodic mesoporous ethylenesilica (PME) was selected as a catalyst support and modified with ethylenediamine through epoxidation of bridging ethylene moieties and the following nucleophilic addition in order to construct base sites. FT-IR measurements for the resulting material, PME-ED, reveal the successful introduction of amino groups into the bridging ethylene moieties. PME-ED can promote Knoevenagel condensation between benzaldehyde and various active methylene compounds as a solid base catalyst. The scope of applicable active methylene compounds in this catalytic system shows the base strength of PME-ED, in which a proton can be abstracted from diethyl malonate (pK a : 16.4) but not from benzyl cyanide (pK a : 21.9). Moreover, the generation of bifunctional catalytic properties to promote a one-pot tandem reaction consisting of alcohol oxidation and Knoevenagel condensation is realised by loading of Au nanoparticles within PME-ED. This catalyst design methodology can be also extended to developing another bifunctional catalyst that is composed of Pd nanoparticles and PME modified with N,Ndimethylethylenediamine in order to promote a Tsuji-Trost reaction.

An efficient and practical method for the synthesis of pyrroles by Cu-catalyzed multicomponent reaction has been described. A range of highly functionalized pyrroles was prepared in good yields under solvent free condition.

In this study, direct Z–scheme heterostructure CoWO4/g-C3N4 was synthesized by a facile hydrothermal method. The structural, morphological properties of the prepared samples were characterised by XRD, SEM, UV–Vis and PL measurements. The as-obtained heterostructure CoWO4/g-C3N4 exhibited enhanced photocatalytic activities toward the degradation of Rhodamine B under visible light irradiation with 92% Rhodamine B removal after 80 minutes irritation, which exceeded pristine g-C3N4 and CoWO4. The enhanced photocatalytic performance ascribed to interfacial contact between g-C3N4 and CoWO4, thus further inhibiting the recombination of photogenerated electron/hole pairs. It is anticipated that the construction of Z–scheme heterostructure CoWO4/g-C3N4 is an effective strategy to develop high-performance photocatalysts for the degradation of organic pollutants in water.

The series x% (wt) Cu2O/g-C3N4 composites were prepared by the conventional impregnation method. These compounds were characterized by different methods such as X-ray Diffraction (XRD), Fourier Transform Infrared spectroscopy (FTIR), UV–vis diffuse reflectance spectroscopy (UV-DRS), and Photoluminescence spectroscopy (PL). The results clearly showed the existence of Cu2O and g-C3N4 phases. The photocatalytic activity was estimated by the degradation of 2,4-Dichlorophenoxyacetic acid (2,4-D). The 5% Cu2O/g-C3N4 catalyst showed the highest activity, with the photodegradation yield reached 7,3%. The addition of H2O2 remarkably improved the yield, with 98,5% attained after 1 hour of irradiation.