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A series of samples of Mg/Zn/Al LDHs (layered double hydroxides) materials was prepared by the co-precipitation and urea hydrolysis methods. They were modified with organic surfactants (acrylate and oleate anions) and characterized by X-ray diffraction, which corroborated the intercalation of anionic species into the interlayer space. The hydrophobized materials were incorporated at low contents (10 and 15 wt.%) to polystyrene, which was synthesized by emulsion polymerization techniques. The polymeric composites were analyzed by thermogravimetry to determine the decomposition temperature. The results demonstrated that the materials with Zn presented the greatest increment in the degradation temperature (7 °C < T < 54 °C). Moreover, the Friedman, Flynn–Wall–Ozawa, and Coats–Redfern models were compared to obtain the kinetic parameters of degradation process. The obtained order of decomposition of the Coats–Redfern model showed that the decomposition process occurs in at least two stages. Finally, the addition of environmentally friendly modified Layered Double Hydroxides (LDH) nanomaterials to the polystyrene (PS) matrix allowed for obtaining polymeric composites with higher thermal stability, retarding the decomposition process of PS.

A series of hydrotalcite-like compounds was synthesized by varying Mg/Al molar ratio with values of 2, 3, and 4. After thermal treatment at 823 K, the corresponding mixed oxides were obtained and used as catalytic supports. The incorporation of a Pd metallic phase (0.5 g/g loading), was carried out by two methods: 1) in situ vapour phase thermal decomposition, and 2) impregnation by organic method. Fresh and calcined samples were characterized by XRD and N 2 sorption experiments. The basic and metal functions were analyzed by CO 2 -TPD and H 2 -TPR. The Pd-support interaction was studied by FTIR spectroscopy using CO as a probe molecule while the morphology of Pd nanoparticles on the catalysts was studied by SEM, HRTEM, and theoretical simulation using the Fast Fourier Transform (FFT) method. Finally, the catalytic activity results showed a higher conversion towards hydrocinnamaldehyde in the cinnamaldehyde hydrogenation reaction for the catalysts prepared by vapour phase thermal decomposition, compared with those prepared by organic method, showing the significant dependence on the catalytic activity and the Pd incorporation method.

The fluorite/perovskite composite with general formula Ce 0.9 Pr 0.1 O 2−δ /Pr 0.6 Sr 0.4 Fe 0.5 Co 0.5 O 3−δ was chemically synthesized by the citrate-EDTA method and subsequent calcination. First, the microstructural and textural properties of the ceramic powder were determined by several techniques such as XRD, N 2 physisorption, SEM, and TEM. Then the catalyst was loaded with Co as a promoter phase. Next, the catalytic evaluations were performed using thermogravimetric analysis to determine the combustion temperature of soot. Moreover, a series of cyclic analyses were carried out to evaluate the thermal stability of the catalyst. Based on the thermogravimetry data, the kinetic parameters of the catalytic soot combustion process were obtained.