Investigations on the microbial activity and anti-corrosive efficiency of nickel oxide nanoparticles synthesised through green route

Abstract

Researchers have shown considerable interest in the environmentally friendly synthesis of several nanoparticles particularly metal nano particles due to their multifaceted applications. The target of the current research includes the synthesis of nickel oxide nanoparticles (NiO-NPs) through the green route using the bark extract from Acacia Nilotica, and analyzed their chemical and surface morphological features using XRD, SEM, EDX, IR, UV–vis and photoluminescence spectroscopy. In addition, the corrosion inhibition ability and antimicrobial activity of the extract were also studied. The XRD analysis indicated that the NiO exist in the form of nanoparticles. It showed the formation of pure cubic NiO-NP with a prominent peak at 43.28° reflected from the plane (200). The crystallite size was found to be 15.83 nm. The SEM micrographs revealed that NiO-NPs appeared to be a bulk cluster-like structure on their surface.The EDX analysis displayed the presence of Ni and oxygen atoms. The photoluminescence spectrum demonstrated that the green synthesized metal oxide nanoparticles have a modified emission band due to the presence of oxygen deficiencies and induced surface imperfections. The Fourier transform infrared spectroscopy (FTIR) confirmed the association of peaks with the C–H and Ni–O bonds. The UV–vis study showed a maximum absorption at 264 nm. A study on the inhibition efficiency towards microbes confirmed that the prepared NiO-NPs have a good inhibition against selected microbes such as S. aureus, E. coli, Candida albicans, A. Niger. The mass loss system showed restraint 93.68 % effectiveness in the mild steel, and the electrochemical study supported the formation of a defensive protective layer on the cathodic locales of the carbon steel surface inhibiting corrosion.