There is no evidence of the presence of secondary phase.
XRD patterns show the presence of split peaks for the
reflections at 400, 422 and 440. This may be due to
presence of Cu‐Kα2 along with Cu‐Kα1 in the X‐ray
radiations used for the diffraction. This is supported by
the fact that in all these reflections the intensity of peaks
due to Cu‐Kα2 is close to 50 % of intensity of peak due to
Cu Kα1 as expected. From the line broadening of the main
peaks, the crystallite size of the ceramic was estimated
using the Debye Scherrer formula [22] :