Zeolitic imidazolate framework-derived nano-cobalt metal/carbon composites for energetic catalysis

The issue of high thermal decomposition temperature and low combustion efficiency of ammonium perchlorate (AP) has long been a concern for the development of high-rate solid propellants. In this work, nano-cobalt metal/carbon (NCM/C) composites, derived from ZIF-67 polyhedrons, are synthesized via a simple carbon thermal reduction method in argon atmosphere. The NCM/C composites are examined as the combustion catalysts for the AP-based solid propellants, particularly on their catalytic effect on AP decomposition. The NCM/C composites notably accelerate AP's thermal decomposition and reduce the primary decomposition temperature of AP from 451.5 to 287.8 °C along with increased heat release from 147 to 955 J g⁻¹. Such excellent performance is attributed to the unique cobalt nano particles encapsulated in N-doped carbon matrix which offers stable and highly active catalysis sites for the oxidation of nitrogen products. In-situ Fourier transform infrared spectroscopy analysis indicates that NCM/C catalysts expedite the oxidation of NO_x products into NO₂ at lower temperatures, thereby enhancing AP's efficacy as a potent oxidant for high-power solid propellants. These findings underscore the promising potential of NCM/C composites as crucial elements in the development of high-burning-rate solid propellants.