High dispersity and ultralight PVP-mediated Al/MFe2O4/g-C3N4 (M = Cu, Mg, Ni) nanothermites synthesized by a novel sol-freeze-drying technology

Abstract

Nanothermite is a reactive system of nanoscale metal-based energetic materials, which is also known as metastable intermolecular composites (MICs). In this study, graphitic carbon nitride (g-C3N4) as a new typical polymer semiconductor was firstly employed to replace GO as an additive in nanothermite. For solving the dispersity of g-C3N4 in nanothermite, a simple and novel sol-freeze-drying technology was firstly proposed to prepare Al/MFe2O4/g-C3N4 (M = Cu, Mg, Ni). The as-prepared Al/MFe2O4/g-C3N4 (M = Cu, Mg, Ni) nanothermites present a similar shape to the host container and have high dispersity, ultralight weight (0.035 g·cm−3) and large specific volume (28.19 cm3·g−1). The optimal PVP and g-C3N4 content were determined. Al/MFe2O4/g-C3N4 (M = Cu, Mg, Ni) all have superior combustion performance, lower electrostatic discharge sensitivity (EDS) and better catalytic performance on ammonium perchlorate (AP) and dihydroxy-lammonium 5,5′-bistetrazole-1,1′-diolate (TKX-50). g-C3N4 plays an important role in suppressing unstable combustion and is beneficial to reduce the electrostatic discharge sensitivity of MICs. This work demonstrates that PVP-mediated sol-freeze-drying technology is an effective approach for obtaining g-C3N4-based nanothermite with high dispersity and ultralight characteristic.