In Situ Generation of Ni Nanoparticles on Al Powder Surface via F‐Ion‐Mediated Oxide Layer Disruption: Enhanced the Energy Release of Oxidizer/Al Composite Energetic Microunits

Designing stable and efficient catalysts is always an immeasurable challenge. It is difficult to achieve efficient dispersion and effective catalysis of catalysts by traditional mixing method. In this study, fuel-catalyst composites with high performance are prepared and aluminum fluoride (AlF₃) encapsulation of nickel (Ni) nanoparticles is also achieved, and it leads to a significant increase in the peak heat flow and heat release during the thermal oxidation process. The loading of Ni nanoparticles on the surface of aluminum (Al) powders improves their dispersion and thus enhances the thermal decomposition rate of the ammonium perchlorate (AP), and reduces its thermal decomposition temperature by 92.14 °C. Meanwhile, the Ni nanoparticles can act as oxygen transport channels to promote rapid oxygen translocation and rapid oxidation of reactive Al powders through the self-cycling aluminothermic reaction. Furthermore, it also enhances the combustion efficiency of the energetic microunits, resulting in an increase in the combustion flame area, flame brightness, and flame growth rate, while the combustion duration is significantly shortened. In conclusion, the new method proposed in this study is able to significantly improve the performance of the oxidant/fuel composite energetic microunits, which is expected to contribute to their widespread application in propellants.