Nanostructured oxidizer of ammonium fluoroferrates with high gas yield and F release capacity to improve the combustion behavior of Al powder

The passivation layer of Al powder hinders the mass transfer during Al combustion. Fluorinated oxidants, such as metal fluorides and fluoropolymers, substantially improve the combustion behaviour of Al powder. Herein, a simple solvothermal method is employed to produce a high-entropy acicular accumulational fluorine-containing oxidiser based on ammonium fluoroferrates. The characterization results indicate that heating the fluorine-containing oxidiser can release gaseous products of HF and NH 3 . HF etches the passivation layer, and NH 3 provides kinetic energy to the fuel, resulting in multiple hot spots and secondary combustion as well as prevention of reaction sintering. Compared with traditional FeF 3 , this novel fluorine-containing oxidiser considerably improves the combustion of Al powder by reducing its onset temperature as well as increasing its exothermic enthalpy, flame area and F release ability.