Electromagnetic and microwave absorption performance of some transition metal doped La0.7Sr0.3Mn1−xTMxO3±δ (TM = Fe, Co or Ni)

In this study the transition metal doped La0.7Sr0.3Mn1−xTMxO3±δ (TM = Fe, Co or Ni, x = 0, 0.2) powders were fabricated by the conventional solid state reaction method. The compositions, morphologies and crystal structures were characterized using different method. The influences of the incorporation of TM into La0.7Sr0.3MnO3±δ on the complex permittivity, complex permeability and microwave absorption performance were investigated in the range of 5.85–18 GHz. It is found that the electromagnetic loss has been enhanced after TM doping. And the microwave absorption properties have been significantly improved. In present study La0.7Sr0.3Mn0.8Fe0.2O3±δ had the best microwave absorption properties. The maximum reflection loss was 27.67 dB at 10.97 GHz, and the absorbing bandwidth above 6 dB was 6.80 GHz with 2 mm thickness.

► The perovskite phase of La0.7Sr0.3Mn1−x(Fe, Co or Ni)xO3±δ (x = 0, 0.2) was formed.
► La0.7Sr0.3Mn1−xTMxO3±δ (TM = Fe, Co or Ni, x = 0, 0.2) had negative susceptibility.
► The electromagnetic loss has been greatly enhanced after TM (Fe, Co or Ni) doping.
► The absorbing peak moved to the lower frequency after TM (TM = Fe, Co or Ni) doping.
► The microwave absorption property was improved after TM (TM = Fe, Co or Ni) doping.