Ionic Energetic Coordination Polymers (IECPs) as a Structural Motif for Ammonium Perchlorate Catalytic Thermal...

As the key oxidizer in solid propellants, ammonium perchlorate (AP) undergoes thermal decomposition that critically governs the ignition and combustion of the propellant. However, the decomposition of AP is incomplete and sluggish due to its high decomposition temperature, multistage process, and insufficient heat release (Q). Therefore, the introduction of catalysts has become the main strategy to improve the thermal decomposition behavior of AP. We report the discovery of novel ionic energetic coordination polymers (IECPs) {[M(TrzAt)₄](ClO₄)₂}_n (M = Co 1, Zn 2; TrzAt = 2-(1,2,4-triazol-1-yl) acetonitrile) as the catalysts for AP. Experimental results indicate the excellent catalytic performance of the two IECPs. Specifically, the mixture of 97 wt % AP with 3 wt % 1 (named 1-3%-AP) exhibits excellent energy-release performance, with the exothermic peak temperature lowering from 445 (pure AP) to 331 °C, the activation energy decreasing from 259 to 139 kJ·mol^-1, and the Q value increasing from 782 to 1792 J·g^-1. Theoretical calculations indicate that the higher adsorption energy of 1 for AP and NH₃ significantly enhances its reactivity, thereby achieving optimal catalytic performance for AP. The outstanding catalytic efficacy of 1 demonstrates the promising potential as a high-performance catalyst for solid propellant applications.