Ligand Denticity‐Driven Structure–Activity Regulation: Performance Differences and Mechanisms of Ferrocene Mono‐/Di‐Hydrazone Copper Complexes in Catalyzing Ammonium Perchlorate Decomposition

Abstract Studying how ligand denticity regulates the catalytic activity of ferrocene hydrazone copper complexes in ammonium perchlorate decomposition, we synthesized mono‐hydrazone (Fc‐MH‐Cu) and di‐hydrazone (Fc‐DH‐Cu) complexes. The complexes were characterized by IR, XPS, SEM, BET, TG‐DSC, and in situ TG‐IR. Ligand denticity critically influences coordination mode, electronic structure, and morphology. Fc‐MH‐Cu forms a flexible chelating structure, lowering the electron cloud density of Cu 2+ and enhancing electron transfer. Its small particle size, high dispersibility, and large pore size enhance AP adsorption, ClO 4 ‐ activation, and product diffusion. This leads to superior catalytic performance, reducing AP's decomposition peaks to 318 °C and 338 °C, with heat release of 1010 J/g and activation energy of 101.9 kJ/mol. In contrast, Fc‐DH‐Cu adopts rigid chelating coordination, increasing the Cu 2+ electron density and limiting electron transfer. Its agglomerated morphology and small pore size hinder mass diffusion, resulting in inferior performance. In situ TG‐IR revealed that Fc‐MH‐Cu promotes deep oxidation of NH 3 to NO 2 at 300–380 °C, whereas Fc‐DH‐Cu mainly produces N 2 O above 340 °C. This work clarifies the role of ligand denticity in regulating the adsorption‐activation‐decomposition synergy, providing guidance for the design of high‐efficiency AP catalysts.