Biosynthesis of Al₂O₃ and europium-doped Al₂O₃ nanoparticle using Cymbopogon citratus (lemongrass) extract and its antibacterial property

Cymbopogon citratus-mediated pure aluminium oxide (Al2O3) and europium (Eu)-doped Al2O3 with different amounts of metal ion were prepared using a green synthesis method. Synthesised nanoparticles were characterised by ultraviolet (UV)-visible spectroscopy, photoluminescence (PL), Fourier-transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD) and scanning electron microscopy (SEM). Synthesis of nanoparticles is confirmed by using UV-visible spectroscopy showing maximum absorption at 411 and 345 nm for Al2O3 and Eu-doped Al2O3, respectively. The antibacterial activity of prepared nanoparticles was evaluated against Pseudomonas aeruginosa, Streptococcus aureus, Escherichia coli and Klebsiella pneumoniae using a well-diffusion technique. The effect of pure Al2O3 and Eu-doped nanoparticles shows excellent results against P. aeruginosa, S. aureus, E. coli and K. pneumoniae.