Enhanced Magnetic Properties of Barium Hexaferrite

The effect of Mn and Co dual-doping on the structural, optical, dielectric and magnetic properties of ZnO nanostructures

“…A thin copper wire joined the electrodes in turn to serve as ohmic contacts. From the measurement of capacitance ( C ), dielectric loss ( ε ′′) and the dimensions of the pellet (thickness and area), the dielectric constant ( ε r ) and ac conductivity ( σ ac ) were determined using eqn (5) and (6) , respectively: 39 σ ac = ε 0 ε ′′ ω where C denotes the capacitance, ε 0 refer to the permittivity of free space (8.85 × 10 −12 m −3 kg −1 s 4 A 2 ), d is the thickness of circular-shaped sample, and A represents the pellet area in m 2 where ω = 2π f is the angular frequency.…”

Enhancing the physical properties and photocatalytic activity of TiO2 nanoparticles via cobalt doping

“…The observed changes in the lattice parameters and a small shift of the diffraction peaks towards the lower angle in Co-doped TiO 2 is also due to the different ionic radius of Co 2+ (0.72 Å) 25 and Ti 4+ (0.68 Å), indicating that the doping of Co 2+ in the TiO 2 matrix is substitutional. 21,26 The following Debye–Scherrer's formula was used to determine the average crystallite size D of the synthesized samples from the XRD spectra: 27 where λ is the wavelength of the incident X-ray, β (in radians) is the angular peak width at half maximum, and θ represents Bragg's diffraction angle.…”

Magnetic Properties and Morphology Copper-Substituted Barium Hexaferrites from Sol-Gel Auto-Combustion Synthesis

“…Examples are Cu 2+ [ 9 , 10 , 11 , 12 , 13 ], Co 2+ [ 14 ], Sm 3+ [ 15 ], Ga 3+ [ 16 ], Cr 3+ [ 17 ], and Ce 3+ [ 18 ]. Moreover, the doping of Ce-Co [ 2 ], Sm-Co [ 19 ], Cu-Zr [ 20 ], Co-Zr [ 21 ], and La-Mn [ 22 ] have been combined in M-type hexaferrites. However, because the magnetic and dielectric properties of ferrites depend on their microstructures and crystal structures depicted in [ 1 , 23 , 24 ], the different values of coercivity and magnetization have been reported.…”

“…However, the results indicate that the effect of Cu doping on the magnetic properties of the barium hexaferrite needs more investigation. From various methods developed to synthesize and dope ferrites [ 1 , 9 , 10 , 11 , 12 , 13 , 14 , 15 , 16 , 17 , 18 , 19 , 20 , 21 , 22 , 23 , 24 , 25 , 26 ], the sol-gel auto-combustion method was selected in this research work to synthesize BaFe 12−x Cu x O 19 (x = 0, 0.1, 0.3, and 0.5) for its cost-effectiveness [ 27 ]. Magnetic properties of BaFe 12−x Cu x O 19 with Cu doping up to x = 0.5 were compared and correlated to their phase and morphology.…”