A combination strategy targeting the combustion enhancement of electrically controlled rocket fuels exerts synergistic elimination against zirconium's electrostatic hazards

Abstract

Developing reliable strategies to enhance the energy density of electrically controlled solid propellants (ECSPs), promising intelligent propulsion fuels, is a challenge due to the potential hazards of typical high-reactivity micro-nano metal fuels induced by the manufacturing procedure involving water. Herein, we reversed the detrimental effect of water to a safety protection characteristic by doping micron-sized Zr@PVP fuel particles into ECSPs. 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 ECSPs 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 propose 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 prospective fate of the zirconium powder with high ESD sensitivity and water-containing electrically controlled propellants possessing poor compatibility with typical high-activity metal powders.