Nanochemistry and biotechnology

Green synthesis and characterization of Zn-doped cobalt ferrites nanoparticles using Ginkgo biloba leaf extract
Liaskovska M.R.1, Tatarchuk T.R.1,2
1 Department of Chemistry, Vasyl Stefanyk Precarpathian National University, 57, Shevchenko Str., Ivano-Frankivsk, 76018, Ukraine. 
E-mail: tatarchuk.tetyana@gmail.com
2 Educational and Scientific Center of Materials Science and Nanotechnology, Vasyl Stefanyk Precarpathian National University, Ivano-Frankivsk, Ukraine.

Green chemistry is considered as one of the techniques applied for nanoparticles synthesis and involves the using of the non-toxic plant extracts as effective reducing agent. In this study, the nanoparticles of Zn-doped cobalt ferrites with the general formula Co1–xZnxFe2O4 (0 ≤ x < 1.0 with step 0.2) have been obtained through the green chemistry method with using of Ginkgo biloba leaf extract. The reducing capability of this plant is based on several reactive components such as polyphenols, terpenoids, amino acids etc. The ferrite nanoparticles were synthesized from Co(CH3COO)2·4H2O, Zn(NO3)2·6H2O and Fe(NO3)3·9H2O as starting materials and plant extract as an effective reducing agent. The powders were characterized using XRD, SEM, EDX, FTIR and Mossbauer spectroscopy. The lattice parameters and crystallite size for samples are obtained from XRD data: a increases from 0,835 to 0,842 nm, while crystallite sizes are in the range 15-20 nm. The FTIR spectra contain two main peaks in the range 600-550 cm-1 and 420-360 cm-1 that correspond to tetrahedral and octahedral sites in spinel structure respectively. The surface morphology of the synthesized spinels shows agglomerated nanoparticles due to their magnetic properties. The cationic distribution was estimated from Mossbauer spectroscopy data. A new antistructural modeling for describing of active surface centers for Co1-xZnxFe2O4 samples is discussed at the first time. 

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