ABSTRACT
This work reports the characterization and application of two promising nanocatalysts for the thermal decomposition of ammonium perchlorate (AP). To obtain these composite materials, magnetite nanoparticles (Fe3O4 NPs) were functionalized with two different amine derivative groups, tertiary amine (Fe3O4 NPs-A1) and quaternary amine. X-ray photoelectron spectroscopy and differential scanning calorimetry provided mechanistic insights into the thermal decomposition of AP. Furthermore, tertiary and quaternary amine groups play a critical role, where the presence of an extra proton could favor an electron-proton transfer as the rate-determining step. Moreover, Fe3O4 NPs-A1 causes a diminution of the high-temperature decomposition of AP positively to 335 °C, increasing the energy release by 278 J g-1 and consequently affording the lowest activation energy (102 kJ mol-1), indicating a low degree of thermal stability, and accelerating the thermal decomposition of AP.
ABSTRACT
We show the synthesis and characterization of four heterobimetallic compounds derived from s-indacene of general formula [{(CO)3Mn}-s-Ic-{MCp*}]q with M = Fe, Co, Ni, and Ru; q = 0, 1+. The complexes reported here were characterized by 1H and 13C NMR, elemental analysis and FT-IR. Additionally, the X-ray crystal structure of [(CO)3Mn-s-Ic-FeCp*] (1) and Mössbauer spectra are reported. The heterobimetallic compounds exhibit higher quasireversible redox potentials compared with ferrocene and catocene under the same reaction conditions. The complexes were tested as catalysts on the thermal decomposition of ammonium perchlorate examined by a differential scanning calorimetry technique to study their catalytic behavior. Compound (1) causes a decrease of ammonium perchlorate's decomposition temperature to 315 °C, consequently increasing the heat release by 138 J·g-1. Conversely, [{(CO)3Mn}-s-Ic'-{CoCp*}] (2) presents a higher heat release (2462 J·g-1), comparable to catocene.
