Oxidation-Level-Tailored rGO in Fe₃O₄/CuO/rGO Nanocomposites: Comprehensive Structural and Thermal Characterization for Enhanced Ammonium Perchlorate Decomposition

A Fe₃O₄/CuO/rGO nanocomposite was synthesized via an ultrasonic-assisted co-precipitation method. Reduced graphene oxide (rGO) with varying oxidation levels was prepared by controlled thermal reduction of graphene oxide in air and subsequently incorporated into the nanocomposite. The structural, morphological, and textural properties were characterized using X-ray diffraction (XRD), Raman spectroscopy, scanning electron microscopy with energy-dispersive X-ray spectroscopy (SEM-EDX), and nitrogen adsorption–desorption analysis (BET). The catalytic performance toward the thermal decomposition of ammonium perchlorate (AP) was evaluated by thermogravimetric analysis (TGA). Uniformly dispersed Fe₃O₄/CuO nanoparticles with diameters of 8–20 nm were observed on the rGO sheets. The nanocomposite containing rGO annealed at 250 °C for 4.5 hours exhibited a high specific surface area of 187.2 m²/g and significantly reduced the AP decomposition temperature by 112.4 °C, highlighting the critical influence of rGO oxidation level on the catalytic performance of the Fe₃O₄/CuO/rGO system.