We developed a two-step synthesis of a mesostructured silicate, which possesses interparticle mesopores with dimensions between 5 and 60 nm. The mesopores are formed by the aggregation of silica nanoparticles, creating a network with interparticle voids. The material was used as a support for MnOx nanoparticles with typical dimensions of 2 nm, which were homogeneously distributed throughout the material. Part of Mn was incorporated also into the silicate framework. This promising environment-friendly catalyst was thoroughly characterized by several spectroscopic methods.
COBISS.SI-ID: 1459963
Kinetics of the isothermal crystallization of tetragonal modification of leucite and hexagonal modification of kalsilite from differently prepared precipitated amorphous aluminosilicate precursors were investigated at three different temperatures. It was shown that the crystallization of leucite occurs the same way as the crystallization of kalsilite and follows a pseudo-zero-rate kinetic equation. The apparent activation energies were calculated and the differences in these energies were explained by the different microstructures of the precursors.
COBISS.SI-ID: 33735173
Mesoporous aluminophosphate thin films with ordered three-dimensional pore systems were synthesized. The mesoporous aluminophosphate framework was thermally stable up to at least 400°C. Small amounts of silicon and manganese were incorporated into the framework. In this way catalitically active centres were generated. The location and the nature of these centres were thoroughly investigated by means of X-ray absorption and NMR spectroscopies.
COBISS.SI-ID: 4470042
Ordered and disordered mesoporous silica supports were used for the immobilization of different amounts of titania. The photocatalytic degradation of isopropanol in the gaseous medium was selected as a probe reaction to test the photoactivity of powders and to verify the potential application of these materials for air remediation. It was found that the titania source, Ti/Si molar ratio and the type of silica support influenced the properties of the material. The adsorption capacity and the photoactivity was the best for the material with SBA-15 as a support and with Ti/Si molar ratio of 1.
COBISS.SI-ID: 1545211
Arrangements associating three aluminium atoms in dealuminated Y zeolites were for the first time detected using a combination of multiple-quantum MAS (MQMAS) and 2D double-quantum homonuclear NMR correlation spectroscopy. From these results, we proposed a model describing the enhanced Bronsted acid sites in dealuminated Y zeolite, consisting in a configuration where framework aluminium pairs are interacting with cationic extra-framework aluminium atoms.
COBISS.SI-ID: 4326426