Structural characterization of green synthesized magnetic mesoporous Fe3O4NPs@ME

• Published in: Materials chemistry and physics 2021-04, Vol.262, p.124323, Article 124323
• Main Authors: Vinayagam, Ramesh, Zhou, Chenxi, Pai, Shraddha, Varadavenkatesan, Thivaharan, Narasimhan, Manoj Kumar, Narayanasamy, Selvaraju, Selvaraj, Raja
• Format: Article
• Language: English
• Subjects: Absorption spectra; BET; Biomedical engineering; Crystallites; Ferric ions; Green synthesis; High temperature; Iron; Magnetic saturation; Magnetite; Magnetite nanoparticles; Mussaenda erythrophylla; Nanoparticles; Structural analysis; Surface area; Surface layers; Synthesis; TGA; VSM; Weight reduction
• ISSN: 0254-0584; 1879-3312
• DOI: 10.1016/j.matchemphys.2021.124323

Mesoporous magnetite nanoparticles (Fe3O4NPs) were synthesized by using the leaf extract of Mussaenda erythrophylla (ME) by a cheap and simple method – green synthesis. The synthesized Fe3O4NPs@ME were characterized by various techniques. A strong absorption spectrum without any specific peak in the UV–vis image designated the formation of iron-containing nanoparticles. XRD image confirmed the presence of only magnetite and the purity was ascertained by the absence of other forms of iron-containing nanoparticles. The average crystallite size was calculated as 18.58 nm and the lattice parameter was 8.38 Å which was close to the magnetite standards. FE-SEM image portrayed spherical aggregates and EDS showed signature peaks for Fe and O elements. XPS image showed the presence of peaks for oxygen, ferrous, and ferric ions which are consistent with magnetite along with carbon on the surface. Mesoporous structure (5.78 nm) was affirmed by BET results which showed a higher surface area (174.15 m2/g) than the commercial one. The FTIR bands obtained at 454.25 and 667.39 cm−1 corresponded to the distinctive Fe–O linkage, substantiating the formation of magnetite. The stability of the magnetite at very high temperature was validated by TGA results which showed a 15% total reduction in weight. The magnetite showed superparamagnetism with a low saturation magnetization value (5.14 emu/g) which confirmed the existence of non-magnetic surface layers arising from the phytomolecules residing in the leaf extract of M. erythrophylla. Hence, the pure, crystalline, and mesoporous Fe3O4NPs@ME with large surface area obtained by the above-mentioned facile procedure will surely make an impact in many areas such as catalysis, adsorption, and biomedical engineering. [Display omitted] •Mesoporous Fe3O4NPs were synthesized by Mussaenda erythrophylla leaf extract.•Spherical aggregates were witnessed in FE-SEM image.•A high specific-surface area of 174.15 m2/g was observed by BET analysis.•Thermal stability was ascertained by TGA which showed 15% weight loss.