Ferrocene-based hydrazone energetic transition-metal complexes as multifunctional combustion catalysts for the thermal decomposition of ammonium perchlorate

Three novel ferrocene-based hydrazone energetic transition-metal complexes denoted as M/E-FcDz-TMCs (M = Co (II), Fe (III), and Co(II)Fe(III)), were successfully prepared to improve the thermal decomposition of ammonium perchlorate (AP) and anti-migration performance of Fc-based catalysts. 1-hydrazinoethylene-ferrocene (E-FcDz) with unique electronic structure and energy bonds (C[dbnd]N, N[sbnd]N) as ligand reacted with transition metal Co, or Fe mono-metal nodes, and Co-Fe bimetal nodes, respectively. The chemical structure, crystalline texture, and morphology were confirmed, and the catalytic performance was investigated. The thermal decomposition kinetics were estimated by applying Kissinger, FWO, and KAS methods. The results revealed that M/E-FcDz-TMCs had superior catalytic performances for AP decomposition compared to the traditional catalyst catocene due to their high electron transport capacity. Especially, CoFe/E-FcDz-TMCs showed the best catalytic efficiency due to the hybridization between Co (II) 3d and Fe (III) 3d orbitals in the structure led to electron redistribution, driving the optimal synergistic catalytic effect of the bimetal Co-Fe nodes and E-FcDz, and further enhancing catalysis for AP. Moreover, AP/CoFe/E-FcDzTMCs showed the best combustion performance. In addition, the thermal decomposition products of AP were explored by TG/FTIR, and the AP thermal decomposition process could be explained by a possible mechanism following the principle of electron transfer theory.