Atomic perspective revealing for combustion evolution of nitromethane/nano-aluminum hydride composite.

Adding aluminum hydride (AlH) into energetic materials (EMs) can improve their combustion and energy performance effectively. However, the potential mechanism of AlH on EMs is still unclear. Based on the ReaxFF-lg method, the thermal decomposition of nitromethane/nano-aluminum hydride (NM/nano-AlH) composites were studied. The addition of AlH reduces the energy barrier and increases the energy release during the decomposition of NM, accelerates the decomposition of NM. The main way of AlH oxidation involves the capture of O atoms from NM. The results show that AlH content and passivated layer affect the oxidation and hydrogen release of AlH. The explosion of small particle size AlH leads to rapid oxidation and hydrogen release. The oxidation of large particle size AlH is dominated by the inward and outward diffusion of O and Al atoms. The products of NM/nano-AlH composites are HO, CO, N gases, and Al clusters. This work is expected to guide the application of AlH in EMs.