Nowadays increasing severity of environmental pollution and antibiotic resistance poses significant global challenges, particularly due to the accumulation of organic pollutants from industrialization and the proliferation of antibiotic-resistant bacteria, which jeopardize ecosystems and public health. To address these issues, the development of advanced nanocomposites with photocatalytic and antimicrobial properties is of paramount importance. This article reports the synthesis of NiCr₂O₄/NiO nanocomposite conducted in the current study via atmospheric pressure microplasma (AMP) electrochemical method. The synthesized nanocomposite’s optical, structural, morphological, and compositional characteristics were thoroughly examined using UV-visible spectroscopy, X-ray diffraction (XRD), scanning electron microscopy (SEM), and Fourier-transform infrared (FTIR) spectroscopy. XRD analysis confirmed the crystalline structure of the nanocomposite, indicating the presence of a cubic spinel phase of NiCr₂O₄ (space group Fd-3m) and a cubic phase of NiO, with a crystallite size of 24.2 nm. SEM analysis demonstrated that nanocomposite exhibited a spherical-like morphology. FTIR spectra showed characteristic metal-oxygen (Ni-O and Cr-O) stretching vibrations at 538 cm⁻¹ and 617 cm⁻¹. UV-visible absorption spectra revealed a broad absorption peak at 377 nm, and the nanomaterial’s optical energy bandgap was estimated to be 2.4 eV. These findings highlight the potential of the NiCr₂O₄/NiO nanocomposite for applications in environmental remediation and antimicrobial treatments.

Keywords: Nickel chromite, atmospheric pressure microplasma, spinel structure

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