Potassium-doped maghemite/graphene for the enhanced catalytic thermolysis of CL-20

The pyrolysis of energetic materials (EMs) directly determines their combustion performance and energy release efficiency. This study designed a potassium-doped maghemite (KF) catalyst with sea urchin-like structure. Traditional lead-based catalyst could cause serious environmental pollution, whereas KF may offer dual advantages of flame suppression and high catalytic activity. Electron paramagnetic resonance (EPR) spectroscopy demonstrate the increased defect concentration compared with commercial γ-Fe 2 O 3 and α-Fe 2 O 3 . The as-prepared KF catalyst provides more surface active sites, significantly enhancing its catalytic performance for the thermal decomposition of hexanitrohexaazaisowurtzitane (CL-20). Graphene oxide (GO) always acts as a stabilizer for EMs due to the excellent mechanical properties. Hence, K-γ-Fe 2 O 3 /reduced graphene oxide (KFG) was prepared via the one-step solvothermal method. Experimental results show that the ternary KFG composite can lower both the initial decomposition temperature and the apparent activation energy of CL-20. KFG accelerates the decomposition process of CL-20 and narrows the distribution of gaseous products. This study reveals the synergistic mechanism among potassium, γ-Fe 2 O 3 , and graphene, providing new design strategy and theoretical foundation for highly efficient combustion catalysts applied in solid propellants.