Precisely regulating combustion and ectrostatic discharge safety properties of Al/CuO nanothermite by inserting g-C3N4 nanosheet.

[Display omitted] • Inserting the semiconductor materials g-C 3 N 4 nanosheet into Al/CuO can improve its safety and precisely regulate the combustion. • More active sites in reaction interface and easier adsorption between metals Al and CuO are induced by polymer polyvinylpyrrolidone (PVP). • The one-step sol-freeze-drying technology is a facile and safety strategy for the preparation of nanothermites. • This work will provide a fresh strategy for extending applications of nanothermites. Nanothermites are presenting competitive advantage potential in military and civilian applications, but high electrostatic discharge (ESD) sensitivity severely hinders their preparation, storage and usage. Aiming to improve the safety and combustion properties of energetic materials (EMs), the two-dimensional semiconductor materials graphite carbon nitride (g-C 3 N 4 also abbreviated as CN) was inserted into the Al/CuO mixture via the one-step sol-freeze-drying method. The successful preparation of samples was confirmed by morphological and chemical bond characterization. Then DFT calculation and BET tests prove that more active sites exist in reaction interface, and the adsorption between Al atoms and CuO unit cells are easier due to polyvinylpyrrolidone (PVP) and g-C 3 N 4 functioning, thereby improving the combustion of Al/CuO and ESD safety. The Al/CuO/CN nanocomposite with 2.5 wt% CN has an ESD ignition threshold of 3.2 mJ and realizes maximal reaction energy and constant volume heat of combustion (Q v) of 1400.4 J·g−1 and 5896 J·g−1, respectively. As the CN content grows to 10.0 wt%, the ESD ignition threshold keeps decreasing to 8.45 mJ. Additionally, PVP and CN show superior advantages in regulating the combustion of Al/CuO, and the possible effect mechanism is investigated. This work will provide a fresh strategy for extending applications of nanothermites. [ABSTRACT FROM AUTHOR]