Green synthesis of silver nanoparticles using Eucalyptus comadulensis leaves extract and its immobilization on magnetic nanocomposite (GO‐Fe₃O₄/PAA/Ag) as a recoverable catalyst for degradation of organic dyes in water

Abstract

The magnetically recyclable graphene oxide‐Fe3O4/polyallylamine (PAA)/Ag nanocatalyst was prepared via a green route using Eucalyptus comadulensis leaves extract as both reducing and stabilizing agent. The catalytic activity of this nanocatalyst was investigated for the reduction reaction of methylene blue and methyl orange in the presence of NaBH4 in aqueous medium at room temperature. The prepared nanocatalyst was characterized by different methods such as Fourier transformed infrared spectroscopy, X‐ray diffraction, scanning electron microscopy–energy dispersive X–ray spectroscopy, thermogravimetric analysis, vibrating sample magnetometer, transmission electron microscopy, and UV–visible spectroscopy. The results show that graphene oxide/PAA/Ag nanocatalyst has good activity and recyclability, and can be reused several times without major loss of activity in the reduction process. The apparent rate constants of the methyl orange (MO) and methylene blue (MB) were calculated to be 0.077 s−1 (3 mg of catalyst) and 0.15 s−1 (2 mg of catalyst), respectively.

Toward a Better Understanding of Metal Nanoparticles, a Novel Strategy from Eucalyptus Plants

“…A few years later, scientist’s attention emerged regarding this plant due to its efficiency in producing MNPs. Thus far, several Eucalyptus species have been adopted to produce MNPs such as E. chapmaniana [ 32 ], E. globulus [ 25 , 26 , 79 , 83 , 84 , 85 , 86 ], E. leucoxylon [ 87 ], E. oleosa [ 88 , 89 ], E. camaldulensis [ 90 , 91 ], E. robusta [ 51 ], and E. tereticornis [ 92 ].…”

“…As shown in Table 1 , AgNPs are the most popular among MNPs synthesized from Eucalyptus , while few studies have been conducted on the synthesis of AuNPs, FeNPs, NiNPs, and bimetallic Fe/NiNPs. Eucalyptus leaves have been vastly used for the synthesis of MNPs [ 51 , 91 , 96 , 97 ] while the bark and wood are rarely used. The use of Eucalyptus leaves to produce MNPs is due to their richness in active substances such as tannic acids, volatile oils, flavonoids, and organic acids [ 93 ].…”

“…Within the sequence of steps in NP biosynthesis, characterization is no less important than the rest of the process, as it is the way to determine the size and morphological structure of the particles [ 14 ]. Characterization of MNPs is carried out by various techniques [ 160 ] such as UV–visible spectroscopy (UV-vis) [ 91 ], scanning electron microscopy (SEM), Fourier transmission infrared spectroscopy (FTIR), transmission electron microscopy [ 31 ], X-ray diffraction (XRD), energy dispersive X-ray spectrometer (EDX), and dynamic light scattering (DLS) [ 39 ]. The most popular techniques used to characterize MNPs derived from Eucalyptus and the functions of each technique are summarized in Figure 6 .…”

Photocatalytic Degradation of Antibiotics via Exploitation of a Magnetic Nanocomposite: A Green Nanotechnology Approach toward Drug-Contaminated Wastewater Reclamation

“…The composite is a mixture of two constituents with distinctive properties to give a material of characteristics better than both constituents taken separately. Components of the nanocomposite have a high surface-to-volume ratio due to their small size and surface activity . A magnetic nanocomposite typically comprises a combination of magnetic NPs, embedded within or dispersed throughout a matrix material (biochar).…”

Green Synthesis of Ag Nanoparticles by Celery Leaf Extract Supported on Magnetic Carbon-Based Biochar Substrate, as a Green Catalyst for Reduction Reactions

“…Recently, the utilization of magnetic nanoparticles (MNPs) as a bene cial material has increased signi cantly owing to their speci c virtues, such as high speci c surface area, superparamagnetic properties, small size, nontoxicity, and large surface-to-volume ratio [35,36]. The accumulation of nanoparticles during the catalytic reaction is one of their impediments [37]. Segregation of nanoparticles from the reaction medium using ordinary methods such as ltration and centrifugation is tough.…”