Co-Doped Rare-Earth (La, Pr) and Co-Al Substituted M-Type Strontium Hexaferrite: Structural, Magnetic, and Mossbauer Spectroscopy Study  

作　　者：Madhav L. Ghimire Dom L. Kunwar Jiba N. Dahal Dipesh Neupane Sunghyun Yoon Sanjay R. Mishra Madhav L. Ghimire;Dom L. Kunwar;Jiba N. Dahal;Dipesh Neupane;Sunghyun Yoon;Sanjay R. Mishra(Department of Physics and Materials Science, The University of Memphis, Memphis, TN, USA;Department of Physics, Virginia Commonwealth University, Richmond, VA, USA;Department of Physics, Kent State University, Kent, OH, USA;Department of Physics and Astronomy, Truman State University, Kirksville, MO, USA;Department of Physics, Gunsan National University, Gunsan, South Korea)

机构地区：[1]Department of Physics and Materials Science, The University of Memphis, Memphis, TN, USA [2]Department of Physics, Virginia Commonwealth University, Richmond, VA, USA [3]Department of Physics, Kent State University, Kent, OH, USA [4]Department of Physics and Astronomy, Truman State University, Kirksville, MO, USA [5]Department of Physics, Gunsan National University, Gunsan, South Korea

出　　处：《Materials Sciences and Applications》2020年第7期474-493,共20页材料科学与应用期刊（英文）

摘　　要：The present study investigates the influence of La³⁺ and Pr³⁺ doping on the structural, magnetic properties, and hyperfine fields of Sr_0.7RE_0.3Fe_12-2x Co_xAl_xO₁₉, (RE: La³⁺ and Pr³⁺, <em>x</em> = 0.0 - 0.8) hexaferrite compounds prepared via auto-combustion technique. The XRD analysis shows a linear decrease in a and c lattice and unit cell volume contraction with the content <em>x</em>. The room temperature magnetic study shows that for the Pr³⁺ doped Sr_0.7Pr_0.3Fe_12-2x Co_xAl_xO₁₉ (Pr³⁺-SrM), the magnetization value monotonically decreases while for La³⁺ doped Sr_0.7La_0.3Fe_12-2xCo_xAl_xO₁₉ (La³⁺-SrM) magnetization value shows a noticeable increase in magnetization value with <em>x</em>. The coercivity of the Pr³⁺-SrM compound was observed to decrease while that of the La³⁺-SrM compound showed a marked 40% increase at <em>x</em> = 0.2 (~5829 Oe) in comparison to undoped SrFe₁₂O₁₉ (~3918 Oe). A difference in Curie temperature was also observed, with Tc ~ 525<span style="white-space:nowrap;">&deg;</span>C at <em>x</em> = 0.4 for Pr³⁺-SrM and Tc = 505<span style="white-space:nowrap;">&deg;</span>C for <em>x</em> = 0.4 for La³⁺-SrM compound. The observed differences in magnetic properties have been explained on the basis of the site occupancy of Co²⁺ and Al³⁺ in the presence of rare-earth ions. The presence of non-magnetic rare-earth ion, La³⁺, improved saturation magnetization, and coercivity and deemed suitable replacement for Sr²⁺. The hyperfine parameters namely quadrupole shift showed a decrease with the La3⁺ or Pr³⁺ doping independent of (Co²⁺-Al³⁺) ions doping. Overall, the Mossbauer The present study investigates the influence of La³⁺ and Pr³⁺ doping on the structural, magnetic properties, and hyperfine fields of Sr_0.7RE_0.3Fe_12-2x Co_xAl_xO₁₉, (RE: La³⁺ and Pr³⁺, <em>x</em> = 0.0 - 0.8) hexaferrite compounds prepared via auto-combustion technique. The XRD analysis shows a linear decrease in a and c lattice and unit cell volume contraction with the content <em>x</em>. The room temperature magnetic study shows that for the Pr³⁺ doped Sr_0.7Pr_0.3Fe_12-2x Co_xAl_xO₁₉ (Pr³⁺-SrM), the magnetization value monotonically decreases while for La³⁺ doped Sr_0.7La_0.3Fe_12-2xCo_xAl_xO₁₉ (La³⁺-SrM) magnetization value shows a noticeable increase in magnetization value with <em>x</em>. The coercivity of the Pr³⁺-SrM compound was observed to decrease while that of the La³⁺-SrM compound showed a marked 40% increase at <em>x</em> = 0.2 (~5829 Oe) in comparison to undoped SrFe₁₂O₁₉ (~3918 Oe). A difference in Curie temperature was also observed, with Tc ~ 525<span style="white-space:nowrap;">&deg;</span>C at <em>x</em> = 0.4 for Pr³⁺-SrM and Tc = 505<span style="white-space:nowrap;">&deg;</span>C for <em>x</em> = 0.4 for La³⁺-SrM compound. The observed differences in magnetic properties have been explained on the basis of the site occupancy of Co²⁺ and Al³⁺ in the presence of rare-earth ions. The presence of non-magnetic rare-earth ion, La³⁺, improved saturation magnetization, and coercivity and deemed suitable replacement for Sr²⁺. The hyperfine parameters namely quadrupole shift showed a decrease with the La3⁺ or Pr³⁺ doping independent of (Co²⁺-Al³⁺) ions doping. Overall, the Mossbauer

关 键 词：Doped Hexaferrite M-Type Hexaferrite X-Ray Diffraction MOSSBAUER 

分 类 号：TM2[一般工业技术—材料科学与工程]