Transition metal-doped porous carbon nitride composites serve as highly reactive catalysts for thermal decomposition of ammonium perchlorate.

The performance of composite solid propellants (CSPs) is influenced by the energy release rate and combustion efficiency of ammonium perchlorate (AP), which serves as their core oxidizer. In this research, porous carbon nitride-based composites doped with transition metals (Mn, Fe, Co, Ni, and Cu) (PCN-M) were rapidly fabricated through precipitation and low-temperature calcination, and were comprehensively characterized. It was found that such additives are conducive to regulating the thermal decomposition pathway of AP and enhancing the combustion efficiency of propellants. The results demonstrate that among the prepared composite materials, PCN-0.5Co exhibits optimal catalytic performance: addition of 5 wt% PCN-0.5Co can reduce the high-temperature decomposition temperature (HTD) of AP by 125.71 °C, lower the apparent activation energy () to 113.04 kJ mol, and shorten the thermal decomposition time by 45.13%. Furthermore, when 2 wt% PCN-2.0Co was applied to HTPB-based solid propellants, the results showed that its thermal decomposition peaks merged into a single exothermic peak, the HTD temperature decreased by 53.5 °C, the combustion rate increased by 39.40% (1.355 mm s), and the heat of explosion increased to 4996 J g. This study provides novel ideas for the design of high-performance AP combustion catalysts and the application of carbon nitride-based materials in solid propulsion engineering.