Burning rate of solid propellants can be effectively improved by adding catalysts and using smaller size ammonium perchlorate (AP). Although few reports, the exploration of changing the size of AP primary particles by catalysts is of great significance for improving combustion performance. Here, taking Co‐bipy as an example, the potential advantages of such materials as AP decomposition catalysts are reported. Due to the existence of NO₃⁻ combined with oxygen rich environment provided by AP, the structural self‐transformation from micronrods to nanoparticles can be quickly realized during the heating process. More importantly, when Co‐bipy decomposes, it can play the role of “scalpel” and in situ cut AP particles. Results show that high‐temperature decomposition of Co‐bipy/AP occurs at 305.8 °C, which is 137.5 °C lower than that of pure AP. Catalytic mechanism is discussed by in situ IR and TG‐IR, CoO can effectively increase the content of reactive oxygen species and weaken the N–H bond, realizing the rapid oxidation of NH₃. Eventually, the behavior of Co‐bipy cutting AP particles is tested. This interesting catalyst structure self‐transformation behavior can not only realize the influence on AP, but also perform a positive function in the combustion process of solid propellants, such as opening the adhesive AP interface.

The combustion performance of solid propellants plays a decisive role in the overall application of rockets. Changing the decomposition behavior of ammonium perchlorate (AP) by adding a catalyst is an effective strategy to control the combustion of solid propellants. Among them, the synergistic catalysis of AP thermal decomposition through different catalytic paths is clearly more efficient. Despite the effectiveness of catalysts, the catalytic mechanism is not clear. In this study, a bimetallic ZnCo–ZIF was used as a catalyst for the thermal decomposition of AP, and the thermal decomposition behavior of AP, actual catalytic component, and the synergistic mechanism of two metals were analyzed. The results showed that ZnCo–ZIF had the best catalytic effect for AP thermal decomposition, high temperature decomposition of AP reached 317.6 °C, and heat release reached 1945 J g⁻¹. The in situ monitoring of gas products via the TG-IR test showed that ZnCo–ZIF could decompose in advance in the presence of AP, while Co₃O₄/ZnO with good dispersion actually played a catalytic role, and the two metal oxides accelerate the decomposition of AP and contribute more heat release through a synergistic effect in the catalytic process. The synergistic catalytic process can be explained by the mechanism of reactive oxygen oxidation and lattice oxidation, and Zn improves the oxidation degree of N and generates nitrogen oxides (N₂O, NO, and NO₂) by releasing lattice oxygen, while Co weakens the N–H bond and accelerates the oxidation of NH₃. These two catalytic processes occur together, reducing the temperature of the AP decomposition peak and increasing heat release. This interesting synergy phenomenon provides experience for exploring synergies between two or more metals.