Synthesis and Characterization of MgO Nanoparticle …
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of parent and stabilizing agent, and pH was maintained constantly as observed in
standardization process. Occurrence of a white precipitate was observed indicating
the completion of the reaction of MgO compound. The precipitate was filtered and
washed with distilled water. The solution was centrifuged at 3000 rpm for 5 min and
the precipitate was dried at 60 °C for 7 h. The white powder is grinded vigorously.
However, the synthesis conditions were optimized for the current reaction by varying
various parameters. Various concentrations of MgNO 3 , ranging from 0.2 M to 0.5 M,
were used with volume 50 ml. The mixture was stirred continuously using a magnetic
stirrer varying the stirring duration from 3 to 5 h and the pH was maintained at values
of 9, 10, 11, and 12 using 0.5 M NaOH solution. The reaction temperature was maintained at 60 and 80 °C. The same temperature at which synthesis was carried out was
used for overnight drying at 60 °C of the precipitate obtained. The absorbance peak
was observed using a UV-Vis spectrophotometer (Eppendorf Biospectrometer). The
band gap (E g ) for this prepared nanoparticles is estimated by Tauc’s equation (αhν)
2
= A(hν-E g ), where hν is the photon energy, α is the absorption coefficient, and A
is a constant relative to the material. The graph of (αhν)
2 versus hν was plotted by
extrapolating the linear portion of the curve to horizontal axis in which (αhν)
2
= 0 in
Fig. 1 (inset). The curve indicates that the value of the direct band gap (E g ) is about
3.89 eV (Khanahmadzadeh et al. 2015). Further, particle size distribution pattern was
observed using dynamic light scattering technique (DLS) (Malvern; Nano-zs90) and
ethanol is used as a dispersant at temperature of 30 °C. Molecular and structural characterization of MgO nanoparticles was characterized by Fourier transform infrared
(FTIR) spectroscopy and transmission electron microscopy (TEM).
Fig. 1 UV-Vis spectrum of MgO nanoparticles. Absorption peak was observed at 275 nm and band
gap was determined as 3.89 eV (as shown in inset figure)
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of parent and stabilizing agent, and pH was maintained constantly as observed in
standardization process. Occurrence of a white precipitate was observed indicating
the completion of the reaction of MgO compound. The precipitate was filtered and
washed with distilled water. The solution was centrifuged at 3000 rpm for 5 min and
the precipitate was dried at 60 °C for 7 h. The white powder is grinded vigorously.
However, the synthesis conditions were optimized for the current reaction by varying
various parameters. Various concentrations of MgNO 3 , ranging from 0.2 M to 0.5 M,
were used with volume 50 ml. The mixture was stirred continuously using a magnetic
stirrer varying the stirring duration from 3 to 5 h and the pH was maintained at values
of 9, 10, 11, and 12 using 0.5 M NaOH solution. The reaction temperature was maintained at 60 and 80 °C. The same temperature at which synthesis was carried out was
used for overnight drying at 60 °C of the precipitate obtained. The absorbance peak
was observed using a UV-Vis spectrophotometer (Eppendorf Biospectrometer). The
band gap (E g ) for this prepared nanoparticles is estimated by Tauc’s equation (αhν)
2
= A(hν-E g ), where hν is the photon energy, α is the absorption coefficient, and A
is a constant relative to the material. The graph of (αhν)
2 versus hν was plotted by
extrapolating the linear portion of the curve to horizontal axis in which (αhν)
2
= 0 in
Fig. 1 (inset). The curve indicates that the value of the direct band gap (E g ) is about
3.89 eV (Khanahmadzadeh et al. 2015). Further, particle size distribution pattern was
observed using dynamic light scattering technique (DLS) (Malvern; Nano-zs90) and
ethanol is used as a dispersant at temperature of 30 °C. Molecular and structural characterization of MgO nanoparticles was characterized by Fourier transform infrared
(FTIR) spectroscopy and transmission electron microscopy (TEM).
Fig. 1 UV-Vis spectrum of MgO nanoparticles. Absorption peak was observed at 275 nm and band
gap was determined as 3.89 eV (as shown in inset figure)