Low-sensitivity ternary nanothermites based on two metal oxides/aluminum and carbon additives

Ternary nanothermites based on CuO–MOx/Al (MOx = SnO2, WO3, Co3O4, MoO3, and BaFe2O4) containing carbon black (CB) were synthesized to investigate the effects of dual-oxidizer coupling and CB on their structural, energetic, and safety characteristics. Carbon black (0–10 wt.%) was incorporated to regulate electrothermal transport and ignition sensitivity. The nanoscale fuel–oxidizer interfaces promoted rapid redox reactions and efficient combustion propagation, while CB enhanced charge dissipation and thermal transport. Increasing the CB content improved the electrical conductivity from 8.65 x 10-5 to 2.965 S cm-1 and increased the electrostatic discharge threshold from 0.19 to 128.5 mJ, indicating significantly reduced electrostatic sensitivity. Thermal and structural analyses confirmed enhanced interfacial reactivity. Among the investigated formulations, CuO–MoO3/Al exhibited the highest energetic performance, with a reaction enthalpy of 1.384 kJ g-1 and a calorific value of 40.1 kJ g-1, whereas CuO–WO3/Al showed the lowest values (0.52 and 13.1 kJ g-1, respectively). Impact and friction sensitivities were also reduced, with thresholds increasing from >48.8 to >74.3 J and from >17.6 to >224.8 N, respectively. Although CB slightly reduced the energy output, it provided an effective balance between energetic performance and operational safety.