Modulating the magnetic properties of Co₃O₄ nanostructures through Sr doping for spintronics applications and...

The development of new magnetic materials with tunable properties has been the focus of significant research because of the quick development of spintronics, which utilizes the intrinsic spin of electrons in addition to their charge. Although Co₃O₄ is a promising material for high-end spintronic devices because of its well-defined magnetic hysteresis, its weak ferromagnetic nature results in low saturation magnetization. In this work, a simple sol-gel approach was employed to synthesize Sr-doped Co₃O₄ nanorods, which were successfully obtained with varying Sr dopant concentrations (1%, 2%, and 3%). With the incorporation of XRD, Raman Spectra, TEM, XPS, UV-Vis spectroscopy, and VSM, the structural, morphological, chemical, optical, and magnetic properties have all been examined. For both pure and doped samples, the XRD data validate the spinel cubic phase Co₃O₄ crystalline structure with the space group Fd3m. The diameter and length of a typical individual nanorod, displayed in TEM images of 3% Sr-doped Co₃O₄, are 14 and 99 nm, respectively, with an aspect ratio of 7.1 nm. The Sr-doped Co₃O₄ NPs' X-ray photoelectron spectroscopy (XPS) shows evidence of dopant incorporation. As the Sr content rises, the band gap falls from 1.50 eV to 1.31 eV, according to UV-Vis spectra. A weak ferromagnetism is established due to the doping, as evidenced by the notable 3% Sr-doped Co₃O₄ nanorods with a robust ferromagnetic characteristic, which exhibit a maximum saturation magnetization of 0.59 emu/g at room temperature, higher than that of pristine Co₃O₄ nanostructures. Additionally, this material contributes to a coercivity of 293.8 Oe and a remanence of 0.05 emu/g. 2% Sr-doped Co₃O₄ exhibited the highest zone of inhibition against S. aureus (18 ± 0.32 mm at 1 mg/ml) among the studied samples, but pristine Co₃O₄ was the most effective against E. coli (15 ± 0.24 mm at 1 mg/ml). Thus, Sr-doped Co₃O₄ nanorods' potential as a promising bioactive material with antimicrobial applications is highlighted by their antibacterial activity. These findings denote the significance and enormous potential of Sr-doped Co₃O₄ in the development of high-performance spintronic devices and antimicrobial applications.