Design and preparation of molecular perovskite-based energetic composite Al@PAP-5 with excellent combustion characteristics.

The assembly of novel high-energy-density compounds with Al powder is considerably important for enhancing and regulating the combustion characteristics of metastable intermolecular composites (MICs). In this study, the molecular perovskite energetic material (H2pz)[Ag(ClO4)3] (PAP-5) was employed as a high-energy component to prepare Al@PAP-5 composites via spray-drying. The effect of the Al/O mass ratio on their micromorphology, thermal properties, and combustion performance was then investigated. The results show that PAP-5 and Al are successfully assembled to form a composite microsphere structure, in which Al exerts a significant catalytic effect on the thermal decomposition of PAP-5, reducing its thermal decomposition peak temperature from 341.9 °C to 310 °C. In addition, a combustion performance test shows that Al@PAP-5 exhibits optimal performance at an Al/O mass ratio of 40 : 60, with a combustion reaction heat and burn rate of 9162 J g-1 and 5.03 cm s-1, respectively. Mechanical sensitivity tests showed that, compared with pure PAP-5, the Al@PAP-5 (40 wt%) composite exhibited significantly reduced impact sensitivity and friction sensitivity, with the values decreasing from 68% to 2% and from 45% to 5%, respectively, indicating a substantial improvement in safety. This study expands the application scope of perovskite energetic materials and provides a guideline for improving and regulating the burn rate of MICs.