Transition metal oxide doped with variable valence metal promote the continuous and efficient decomposition of ammonium perchlorate

Although ammonium perchlorate (AP) is now one of the most widely used oxidants in solid propellants, it is a great challenge that the energy release is not concentrated during the decomposition of AP due to the two-stage decomposition. In order to address this challenge, we designed a strategy that defects generated by heteroatom-doped (Fe, Ce) catalysts induce electron transfer to promote AP continuous decomposition. Due to the presence of defects, the catalytic active site is generated, which forms a Lewis acid-base pair with NH₃, causing NH₃ to leave the surface of the reactant rapidly, resulting in the disappearance of the high-temperature decomposition peak. Due to the unique oxygen conduction function of Ce, metal oxides doped with Ce are generally superior to those doped with Fe. Take Co₃O₄@Ce and Co₃O₄@Fe, which have the best catalytic effects, as examples. The decomposition temperatures of AP were reduced to 300.16 °C and 340.28 °C respectively, and the activation energies of AP decomposition were reduced to 114.49 kJ/mol and 150.33 kJ/mol respectively, which confirmed that Ce has better catalytic efficiency. In addition, given the oxygen enrichment effect of CeO₂, AP tended to dissociate deeply on the crystal plane of Co₃O₄. The product analysis showed that NH_x produced by AP decomposition was oxidized rapidly under the synergistic action of Co and Ce, and more O₂ was produced at the same time. As a result, the strategy of constructing defect-rich catalysts by doping atoms has great application prospects in AP catalysis.