Active colloidal catalysts inspired by glutathione peroxidase (GPx) were synthesized by integration of catalytically active selenium (Se) moieties into aqueous microgels.A diselenide crosslinker (Se X-linker) was successfully synthesized and incorporated into microgels through precipitation polymerization, along with the conventional crosslinker N,N'methylenebis(acrylamide) (BIS). Diselenide bonds within the microgels were cleaved through oxidation by H 2 O 2 and converted to seleninic acid whilst maintaining the intact microgel microstructure.T hrough this approach catalytically active microgels with variable amounts of seleninic acid were synthesized.R emarkably,t he microgels exhibited higher catalytic activity and selectivity at lowr eaction temperatures than the molecular Se catalyst in amodel oxidation reaction of acrolein to acrylic acid and methyl acrylate.

The paper is dedicated to studies of kinetic regularities of oxidation of unsaturated aldehydes by organic peracids. The routes of products formation were considered, kinetic model of the oxidation reaction was designed and reaction activation parameters were calculated based on experimental data. New data on reactivity of aldehydes with various structures in the reaction with peracids were obtained.

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Micro-mesoporous tin phosphate is prepared via precipitation under acid medium with subsequent modification using hydrothermal, microwave, and mechanochemical treatments (HTT, MWT, and MChT, respectively). The structure of the initial and modified samples is studied using nitrogen adsorption-desorption, DTA-TG and XRD analysis, FTIR spectroscopy, and SEM. Selected samples are tested as catalysts in aldol condensation of formaldehyde with acetic acid and in photocatalytic degradation of safranin T under visible irradiation. It is established that modification, primarily under hydrothermal conditions, results in the formation of mesoporous or meso-macroporous structure which is more accessible for the reagents molecules and more resistant to sintering and coking at higher temperature. Maximum effect is obtained in the case of modification of wet gel. Catalytic performance of the tested samples in aldol condensation is primarily determined by the parameters of their porous structure. The acquisition of photocatalytic activity is due to the narrowing of the band gap as a result of modification.

Molybdenum disulphide (MoS2) is a layered material with interesting photocatalytic properties.