Precision-Targeted N–H and Cl–O Bond Cleavage: Trinuclear Ferrocenyl Coordination Compounds as Efficient Catalysts for Ammonium Perchlorate Decomposition

Abstract

Two novel trinuclear ferrocenyl coordination compounds, Fc₃N₄/Fe and Fc₃N₄/Co, were synthesized as burning-rate catalysts for ammonium perchlorate (AP). The trinuclear architecture, featuring a nitrogen-rich ligand bridging three ferrocene units with transition metal centers, was designed to enhance multi-site electron transfer and thereby promote catalytic performance. At 3 wt% loading, Fc₃N₄/Co reduced AP's high-temperature decomposition temperature by 126°C, decreased the apparent activation energy by 74.0 kJ · mol⁻¹, and increased heat release by 718 J · g⁻¹, outperforming the corresponding mononuclear analogues and commercial binuclear ferrocene catalysts. Structural characterization (XRD, BET, XPS) and DFT calculations suggest that the superior catalytic activity arises from synergistic Co–Fe electronic modulation that facilitates N–H and Cl–O bond activation, together with a high specific surface area (310.6 m² · g⁻¹) that provides abundant active sites. This work establishes trinuclear ferrocenyl coordination compounds as a promising platform for high-performance burning-rate catalysts in composite solid propellants.