Mössbauer, optical, magnetic, electrochemical and antibacterial studies of the Ag/Sr0.85Ag0.15FeO3−δ composite

Abstract

Abstract In this study, Ag/Sr0.85Ag0.15FeO3−δ composite was prepared by sol-gel method. The structure, morphology, and surface properties of this composite have been characterized by X-ray diffraction (XRD) combined with Rietveld analysis, transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), and Mössbauer spectroscopy. XRD and TEM results confirm the existence of the perovskite phase of Sr0.85Ag0.15FeO3−δ and Ag nanoparticles. XPS and Mössbauer spectroscopy results indicate the existence of oxygen vacancies (δ) and different oxidation states of Fe ions. The band gap energy (Eg) of this composite is 3.53 eV and lies in the UV region. The magnetic hysteresis loop (M-H) of this composite reveals the existence of an exchange bias effect because of the competition between antiferromagnetic (AFM) and ferromagnetic order (FM). Electrochemical measurements indicated that the Ag/Sr0.85Ag0.15FeO3−δ composite exhibits pseudocapacitive behavior. The present composite showed strong antimicrobial activity to fight both tested Gram-positive and Gram-negative bacteria as well as unicellular and filamentous fungi strains.