Facile Synthesis of Ag–γ-Fe2O3 Superior Nanocomposite for Catalytic Reduction of Nitroaromatic Compounds and Catalytic Degradation of Methyl Orange

A facile synthetic route for preparing silver-doped maghemite (Ag–γ-Fe 2 O 3 ) nanocomposite via a modified co-precipitation method was developed. The prepared magnetic nanocomposite was characterized by means of thermal analysis, transmission electron microscope, X-Ray diffraction, vibrating sample magnetometer and Fourier transform infrared techniques. The characterization results showed that the prepared Ag–γ-Fe 2 O 3 nanocomposite is nanocrystalline and 6–8 nm in size with superparamagnetic behavior. The synthesized Ag–γ-Fe 2 O 3 nanocomposite showed exceptional catalytic activities towards reduction of nitroaromatic compounds with specific activities parameters of 1441.7 and 904.2 s − 1 g Ag −1 for both 4-nitrophenol and 2-nitroaniline, respectively. Besides, it shows a superior activity for catalytic degradation of methyl orange. All the three catalytic reactions were carried out in aqueous medium at room temperature and in the presence of reducing agent NaBH 4 . The magnetic behavior of the synthesized Ag–γ-Fe 2 O 3 enables the ease of separation of the nanocomposite from the reaction medium for further reuse. Graphical Abstract