MOX (M = Zn, Co, Fe)/AP shell–core nanocomposites for self-catalytical decomposition of ammonium perchlorate

Abstract

To overcome the agglomeration of metal oxide (MOX) nanocatalysts mechanically mixed with ammonium perchlorate (AP) and other additives of rocket propellant, the shell–core nanocomposites of MOX/AP have been synthesized successfully by a facile liquid deposition method at room temperature. SEM analysis revealed that MOX (M = Zn, Co, Fe) nanoparticles were deposited on the surface of AP particles as either a continuous thin layer or small clusters. Owing to the existence of the shell of MOX nanocatalysts, ZnO/AP, Co 3O 4/AP and Fe 2O 3/AP nanocomposites showed excellent self-catalytic performances for AP thermal decomposition: lowering the decomposition temperature from 398 °C to 272 °C, 285 °C, 337 °C, and increasing the heat release from 584 J g −1 to 1137 J g −1, 1237 J g −1, 1010 J g −1, respectively. Moreover, their self-catalytic performances mainly relied on the content of MOX nanocatalysts, which was controlled by the concentration of metal salts in the precursor solution. In particular, ZnO/AP nanocomposites with the mass ratio of ZnO:AP = 4:100 exhibited the best self-catalytic performance in decreasing the activation energy from 154.0 kJ/mol to 96.5 kJ/mol. The MOX/AP (M = Zn, Co, Fe) shell–core nanocomposites could have a promising application in the rocket propellant for improving the thermal-catalytic decomposition performance of AP.