A combination strategy targeting combustion enhancement for electrically controlled rocket fuel exerts synergistic divestiture against zirconium’s electrostatic hazards

Reliable strategies to enhance the energy density of electrically controlled solid propellant (ECSP), a promising intelligent propulsion fuel, is a challenge due to potential hazards for typical high-reactivity micro-nano metal fuels induced by manufacturing procedure involving water. Herein, we reversed the detrimental effect of water to a safety protection characteristic by doping micron-sized Zr@PVP fuel into ECSP. Zr@PVP composite particles with low electrostatic discharge (ESD) sensitivity were fabricated by coating Zr with PVP containing hydrophilic groups, which were suitable for one-pot fabrication of fully electrostatically isolated ECSP owing to the contribution of water to electrostatic shielding. Pyrolysis characteristics revealed that Zr could promote concentrated-rapid exothermic decomposition of the propellant due to possible compositional catalytic effects. Electrically controlled combustion diagnosis demonstrated that Zr significantly enhanced propellant combustion. Accordingly, we proposed the potential mechanism of excited-Zr to form fireballs as a "hot spot" that continuously triggers the diffusion combustion of highly reactive intermediates. Our efforts provide a prospect-fate for the zirconium powder with high ESD sensitivity and water-containing electrically controlled propellants possessing poor compatibility with typical high-activity metal powders.