Core-shell nAl@Fc-Fx nanocomposites with dual function: Combustion and anti-migration performance

In this study, three fluoro-containing ferrocene compounds (Fc-Fx) with different fluorine and Fc contents were prepared and then be coated on the surface of nanoaluminum (nAl) to increase the combustion performance of nAl and the anti-migration performance of Fc. By removing the aluminium oxide (Al₂O₃) shell and instead constructing a new Fc-Fx shell with a thickness of 5–30 nm on the surface of nAl, the obtained nAl@Fc-Fx nanocomposites showed enhanced performances in i) anti-migration and ii) combustion performances owing to the Al-F interaction and the intimate contact between nAl and Fc-Fx. Among all three nAl@Fc-Fx nanocomposites, nAl@Fc-F2 with the longest fluorine chain could shorten the ignition delay time from 1.83 s to 1.03 s and nAl@Fc-F3 with highest Fc content could decrease the decomposition temperature of ammonium perchlorate to 328 °C. When the nAl@Fc-Fx nanocomposites were applied in the propellants, a shorter migration length (0.1–0.4 cm) was achieved as compared with the physically mixing nAl/Fc compound (3.0 cm), which was beneficial to enhancing their burning performance. This work demonstrated that nAl@Fc-Fx nanocomposites had great potential to be applied in solid rocket propellants.