3.2 XRD Analysis
Figure (5-a) shows the diffraction pattern of the synthesized samples. The diffraction patterns of the synthesized samples contain nanoparticles (NiFe2O4), amorphous SiO2 particles and a metal-organic framework containing copper (HKUST-1). These diffraction patterns are consistent with other reports [43-45]. An increase in concentration (NiFe2O4) and a decrease in silica substrate concentration are clearly visible at peak 24 ° and sharpening of peaks (NiFe2O4). According to reports, the peaks observed in the range of 15-20 are related to the presence of a metal-organic framework containing copper. Peaks in the range of 30-40 are related to the presence of nickel ferrite in the silica bed which confirms the existence of a metal-organic framework containing copper (HKUST-1) and nanocomposites (NiFe2O4). The main peaks of the synthesized magnetic metal-organic nanocomposite frame include 16.05, 19.9, 42.24, 74.35, 28.37, 47.43, 57.53, 55.57, 72.62; that in all three patterns, peaks related to MOF and nanoparticles (NiFe2O4) are observed. Figure (d-5) shows the pattern of nickel ferrite nanocomposites in silica substrate and compared with the reference peaks of nickel ferrite (5-b) and silica (5-c) nanoparticles [46,47]. This diffraction pattern showed that the peaks include nickel ferrite index peaks with cubic spinel structure Fd3m which represent the plate group (2 2 7) and silica lattice index peaks which represent the plate group (2 2 0). These results showed that the nanocomposite was synthesized correctly, and its pattern was consistent with the existing reports [46-50].
The Scherer equation (Equation 2) was used to calculate the average crystal size using the XRD model.