X-ray diffraction (XRD) data were obtained with Rigaku D/max
2500 diffractometer (Cu Ka radiation, l ¼ 0.154056 nm) at 40 kV
and 30 mA, the samples were scanned with Bragg's angles between
10 and 85 at a rate of 4/min, the phase identification was
determined by comparison with the Joint Committee on Powder
Diffraction Standards (JCPDS), the crystallite diameter of the samples
were estimated from XRD patterns applying the Scherrer
equation.