Hollow flower-like nickel particles as the promoter of ammonium perchlorate-based solid propellant

Abstract

Hollow flower-like nickel particles were prepared by a facile polyol method, and applied to solid propellant as combustion promoter. Ni[C2H4(NH2)2]3(COOH)2 complex was used to fabricate hollow flower-like intermediate in ethylene glycol (EG), and then the intermediate was calcined and auto-reduced in nitrogen to obtain the hollow flower-like nickel particles. The hollow particles' shell thickness is about 120 nm, and the petals' thickness of the flower structure is about 10 nm. Importantly, the hollow spheres' diameter can be accurately controlled from 200 nm to 2 μm by adjusting the concentration of complex Ni[C2H4(NH2)2]3(COOH)2 in the reaction solution. The growth of the hollow flower-like particles was illustrated as an extraordinary growth-shrink-collapse process by analyzing the intermediate's morphologies as reaction going on. By adding a certain amount (typically 5 wt%) of the prepared nickel powders, the exothermic decomposition of ammonium perchlorate, which is the main component of solid propellant, was well promoted. The decomposition temperature was decreased by about 140 °C, and the exothermic peak at higher temperature shifted to the lower temperature range, heat released of AP's decomposition also increased by about 150%.