Eco-Friendly Synthesis of Ni/NiO Nanoparticles Using Gymnema sylvestre Leaves Extract for Antifungal Activity

Abstract

The invention of an easy synthetic approach for extremely impactful nanomaterials (NMs) is one of the crucial research areas in modern science and engineering. In the present work, we describe a cost-effective, simple, rapid and environmentally gracious biogenic fabrication of nickel/nickel oxide nanoparticles (Ni/NiO NPs) using Gymnema sylvestre as a natural fuel. The textural characteristics of as-prepared Ni/NiO NPs were explored using X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), diffuse reflectance spectra (DRS), photoluminescence spectroscopy (PL), field-emission scanning electron microscope (FESEM), energy dispersive X-ray analysis (EDX), and high-resolution transmission electron microscopy (HRTEM). XRD affirmed the crystalline nature and phase formation of Ni/NiO NPs. The FTIR spectrum ascertains the formation of Ni/NiO NPs, and the band gap of 4.29 eV is revealed from DRS studies. Ni/NiO NPs display an intense emission peak at 576.2 nm in their PL spectrum. The fabrication of pseudo-spherical Ni/NiO NPs was displayed by FESEM and HRTEM images. The particle size obtained from HRTEM was 21 nm, which resembles the median crystallite size ascertained from the XRD data. Additionally, the plausible mechanism for Ni/NiO NPs formation is illustrated. Moreover, as-synthesized Ni/NiO NPs displayed considerable antifungal potential against Candida albicans and Aspergillus niger. Results revealed that the Gymnema sylvestre leaves extract can synthesize Ni/NiO NPs with appealing biological effectiveness for application in the nanomedicine sector.

Synergistic Anticandidal Effectiveness of Greenly Synthesized Zinc Oxide Nanoparticles with Antifungal Agents against Nosocomial Candidal Pathogens

“…The phytochemicals in S. officinalis extract reduce the zinc nitrate solution, resulting in the development of a reddish-brown precipitate, affirming the formation of zinc oxide nanoparticles. The phenolic compounds present in plant extracts play a role as both reducing and stabilizing agents in the synthesis of biogenic ZnO-NPs, preventing particle aggregation and providing antioxidant properties [ 33 , 45 , 46 ]. Previous studies have provided a mechanistic pathway for producing ZnO-NPs based on the chemical constituents of plant extracts.…”

Synthesis and Characterizations of Fe-Doped NiO Nanoparticles and Their Potential Photocatalytic Dye Degradation Activities

“…The optical absorption of pure NiO nanoparticles was observed at 285 nm, indicating high energy transitions in the UV region of the spectrum. The peaks of the Fe-NiO nanoparticles were exhibited at 300-350 nm and their absorbance decreased as the concentration of Fe doping increased [52].…”

“…The decrease in the bandgap energy and the increase in the visible-region absorbance can be attributed to the higher concentration of Fe ions in the NiO lattice, which introduces the high-energy electron occupations on the nanostructure surfaces. Fe dopants deduced more defects and impurities, which act as recombination centers for electron-hole pairs, enhancing the photocatalytic activity [52][53][54][55][56][57][58][59][60]. Nonetheless, the bandgap energy of Fe-NiO is still within the visible-light range, making it suitable for photocatalytic applications when exposed to visible light.…”