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Novel heterogeneous catalyst systems comprised of palladium nanoparticles immobilized into the nanospaces of imidazolium-based bifunctional plugged and unplugged periodic mesoporous organosilicas (BFPMO) have been described for the selective aerobic oxidation of alcohols in water. BFPMOs were characterized by N2 adsorption–desorption analysis, transmission electron microscopy (TEM), powder X-ray diffraction (PXRD), thermal gravimetric analysis (TGA), 29Si and 13C cross-polarization magic angle spinning (CP MAS) NMR spectroscopy, diffuse reflectance infrared Fourier transform spectroscopy (DRIFT), elemental analysis, scanning electron microscopy (SEM), and X-ray photoelectron spectroscopy (XPS). The catalytic activity of all plugged and unplugged catalysts was investigated in the aerobic oxidation of benzylic alcohols by emphasizing the effect of different physiochemical properties as well as the plugs on the reaction selectivity. While unplugged catalysts exhibited much better activity for the selective oxidation of benzyl alcohol to benzaldehyde, the selectivity pattern shifts to the benzoic acid in high yield and selectivity in the presence of plugged catalyst under the exact same reaction conditions. The studies showed for the first time that varying the hydrophobic–hydrophilic balance with concomitant control of plugs in the interior of the mesochannels of the described catalyst enabled tuning of both the catalyst performance and the reaction selectivity, possibly through a cooperative mechanism. A possible model has been proposed to explain this unprecedented observation.

An unprecedented synergistic effect, obtained for rationally designed Au-Pd alloy nanoparticles supported on an acidic metal-organic framework (MOF), in the aerobic oxidation of the primary C-H bonds in toluene and derivates is reported.

The substituent effect on the dynamics of deactivation of the first singlet excited state of para-substituted salicylideneaniline in octanol was investigated using multifrequency phase and modulation fluorometry. On the basis of the temperature dependence and by use of the global analysis approach to the excited-state reaction scheme, we have determined the rate and the activation energy for the cis-keto* → twist-keto* process. It has been found that the activation energy increases when the electron-donor strength of the substituent increases.

ZnO nanocrystals of different shapes and sizes have been synthesized using an innovative methodology and various polysaccharides as sacrificial templates.

Hierarchical Beta zeolites with different Si/Al molar ratios, synthesized by crystallization of silanized protozeolitic units, were investigated in the liquid-phase Beckmann rearrangement of cyclohexanone and cyclododecanone oximes.

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