Large Coercivity In Antiferromagnetic Mn2o3/Mn5o8 And Mno/Mn Nanoparticles

Mn2O3/Mn5O8 and MnO/Mn nanoparticles were prepared by annealing manganese nanoparticles in air and hydrogen, respectively. The antiferromagnetic Mn2O3/Mn5O8 and MnO/Mn nanoparticles exhibit anomalous magnetic properties, such as large moments, and large coercivity of up to 169 kA/m and 105 kA/m, respectively. This ferromagnetic-like behavior is attributed to the finite size effect of antiferromagnetic nanoparticles and the presence of ferrimagnetic Mn3O4 phases.