Green synthesis of cotton flower shaped nickel oxide nanoparticles: Anti-bacterial and tribological studies

• Published in: Inorganic chemistry communications 2023-11, Vol.157, p.111239, Article 111239
• Main Authors: Uma Ravi Sankar, A., Kiran, Y.B., Madhu Mohan, V., Kiran Kumar, A.B.V., Venkata Varalakshmi, M.
• Format: Article
• Language: English
• Subjects: Antibacterial activity; Cassia Fistula plant extracts; Nickel oxide nanoparticles; Sol-gel; Tribological studies
• ISSN: 1387-7003; 1879-0259
• DOI: 10.1016/j.inoche.2023.111239

Fig. 1. Schematic diagram of NiO-NPs using Green synthesis approach. [Display omitted] •Green synthesis of NiO-NPs in presence of Cassia Fistula Plant Extract.•To understand morphology, crystalline and elemental composition NiO-NPs characterised using SEM, XRD and EDS.•We have studied NiO-NPs antimicrobial properties against Gram positive and gram-negative bacteria such as S.aureus, S.epidermis,K. pneumonia and E.coli.•Tribological studies also conducted for NiO-NPs. The goal of this study was to synthesize nickel oxide nanoparticles (NiO-NPs) by the sol–gel method, which involved the use of Cassia Fistula is a herbal and medicinal plant. The Cassia Fistula (CF) plant extract acts as a stabilizing and capping agent. Further, NiO-NPs were characterized using UV–Visible spectroscopy (UV–Vis), Powder X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), Scanning electron microscopy (SEM) and Energy Dispersive X-Ray Spectroscopy (EDX). According to the results of UV–Visible, the absorption spectroscopy has displayed that the band gap is 3.5 eV. The biological properties were studied for prepared NiO-NPs. The antibacterial testes were examined using different bacterial strains such as Escherichia coli, Staphylococcus aureus and Staphylococcus Epidermis and dose-dependent inhibition response was reported. The tribological tests are carried out using four ball testers in accordance with ASTM D4172-18 requirements. NiO-NPs are utilised as lubricating additives in poly alpha olefin (PAO4) base oil. NiO-NPs in PAO4 at a concentration of 0.5 wt% improved the coefficient of friction, and positive results are observed.