Insights into the structure and magnetic characteristics of Ho substituted Ca-Cu based Ca0.5Cu0.5Fe12-xHoxO19 hexaferrites nanoparticles

Abstract

This work demonstrates a systematic attempt to explore the structure and magnetic properties of Ho³⁺ substituted Ca-Cu hexaferrite nanocrystals. Ca_0.5Cu_0.5Fe_12-xHo_xO₁₉ (x = 0.00, 0.05, 0.10, 0.15, 0.20) M−type hexaferrites are synthesized via sol–gel auto combustion technique. XRD spectra is used to evaluate the phase, and substituent-induced modifications of crystallites. The lattice parameters ‘a’ and ‘c’ lies in the range (5.887–5.898) Å and (23.184–23.195) Å. The size of crystallites ranges from 55.73 to 59.41 nm. The specimen’s morphology indicates the consistent distribution of grains with Ho substitution. The coercivity of samples increased slightly from 2.85 to 3.15 kOe, as determined by vibrating sample magnetometer (VSM) loops, whereas saturation magnetization increased from 26.41 to 30.13 emu/g. The discussion also encompasses variations in anisotropy field (Ha), anisotropy parameter (B), magneto-crystalline anisotropic constant (K), and magnetic moment per formula unit m_B(µ_B) and their effect on main magnetic parameters.