Solid combustion synthesis of MnO2/NiO/Ag nanocomposites for efficient degradation of methylene blue and their antibacterial activity

This study was undertaken to design simple, eco-friendly, and easy recoverable MnO2/NiO/Ag (MnCs) nanocomposites, which were synthesized by solid combustion method. Various techniques were utilized to analyze the morphology, composition, functional groups, and optical properties of both MnO2 and its MnCs composites. SEM and TEM images confirmed the surface morphology and particle distribution. The bandgap energies of MnO2, MnCs-1 and MnCs-2 were determined through Kubelka-Munk equation as 1.8, 1.77 and 1.75 eV, respectively. The binding energies obtained from the XPS spectra were 642.89 and 654.04 eV confirming the presence of Mn2p(3/2) and Mn2p(1/2). The photocatalytic activity of MnO2, MnCs-1, and MnCs-2 was investigated for the degradation of MB dye, revealing that approximately 43.24 %, 75.50 %, and 91.25 % of MB was degraded under UV-light after 120 min. Furthermore, the MnO2/NiO/Ag nanocomposites exhibited a zone of inhibition against pathogens, including Staphylococcus aureus, Streptococcus pyogenes, Escherichia coli, and Klebsiella pneumoniae.