Synthesis, characterization and catalytic activity of manganese oxidic nano-particles
(EN)
Skordilis, C. S.
(EN)
Πανεπιστήμιο Ιωαννίνων. Σχολή Θετικών Επιστημών. Τμήμα Χημείας
(EL)
Skordilis, C. S.
(EN)
Manganese oxidic nano-particles have been prepared via hydrolysis of a trinuclear manganese complex [Mn3O(CH3COO)(6)(pyr)(3)]ClO4. The obtained particles are amorphous and crystallize to Mn2O3 at T > 500 degrees C. Their BET specific surface area is 150-200 m(2) g(-1) at 200 degrees C > T > 400 degrees C and diminishes to 50 m(2) g(-1) at 500 degrees C and 10 m(2) g(-1) at 650-700 degrees C. The pore volume distribution of the particles heated at 200 degrees C shows a maximum at 5.5 nm while almost 95% of the pores lies between 4 and 12 nm. In SEM it seems that the obtained particles are almost spherical with diameter 0.1 - 0.2 mu m. The obtained particles are active for the N2O decomposition, which was used as a probe reaction, above 300 degrees C. Activation energies calculated assuming first order kinetics are around 100 kJ/mol. Comparison with other catalysts containing manganese in oxidic form, like perovskites, conventionally prepared manganese oxide by precipitation of Mn(OH)(2) and manganese oxidic nano-particles supported on clay, shows that the activity of the nano-particles, calculated either per unit mass or unit area of active phase, is higher as referred to the other systems.
(EN)
