In-Situ Growth of Bimetallic ZnCo-ZIF-67 on Carbon Fibers as High-Efficiency Catalyst for Enhancing Thermal Decomposition of Ammonium Perchlorate

Due to its abundant active sites, the bimetallic zeolite imidazole framework ZnCo-ZIF-67 exhibits excellent catalytic performance on the key oxidant ammonium perchlorate in composite solid propellants. In addition, carbon fiber has been proven to promote the combustion of propellants due to its high thermal conductivity efficiency. In order to integrate the advantages of both, this study designed and prepared a novel composite catalyst, ZnCo-ZIF-67/CF, by a co-precipitation method. The thermal decomposition test demonstrated that the ZnCo-ZIF-67/CF composite exhibited significant catalytic activity. When the addition amount was 5 wt%, the high-temperature decomposition peak temperature of AP decreased significantly from 424.3 °C to 337.2 °C, and the combustion process was also significantly accelerated. Furthermore, analysis of the products of thermal decomposition gases revealed a significant increase in the proportion of N2O in the catalyzed products to 55.7%, whilst the proportion of high oxidation state nitrogen-containing oxides such as NO2 and NOCl decreased. This finding suggests that the highly dispersed metal active sites in ZnCo-ZIF-67/CF synergistically promote the decomposition reaction pathway of AP, leading to enhanced N2O generation. This study proposes a novel approach for the development of efficient and stable AP decomposition catalysts, which has positive significance for the regulation of the combustion performance of propellants.