Absence of ferromagnetism in Mn-doped tetragonal zirconia

Abstract

International audienceIn a recent letter, it has been predicted within first principle studies that Mn-doped ZrO2 compounds could be good candidates for spintronics application because expected to exhibit ferromagnetism far beyond room temperature. Our purpose is to address this issue experimentally for Mn-doped tetragonal zirconia. We have prepared polycrystalline samples of Y0.15(Zr0.85−yMny)O2 (y = 0, 0.05, 0.10, 0.15, 0.20) by using standard solid state method at equilibrium. The obtained samples were carefully characterized by using x-ray diffraction, scanning electron microscopy, elemental color mapping, x-ray photoemission spectroscopy, and magnetization measurements. From the detailed structural analyses, we have observed that the 5% Mn doped compound crystallized into two symmetries (dominating tetragonal and monoclinic), whereas higher Mn doped compounds are found to be in the tetragonal symmetry only. The spectral splitting of the Mn 3s core-level x-rayphotoelectron spectra confirms that Mn ions are in the Mn3+oxidation state and indicate a local magnetic moment of about 4.5 μ B/Mn. Magnetic measurements showed that compounds up to 10% of Mn doping are paramagnetic with antiferromagnetic interactions. However, higher Mn doped compound exhibits local ferrimagnetic ordering. Thus, no ferromagnetism has been observed for all Mn-doped tetragonal ZrO2 samples

Oxygen vacancy induced photoluminescence properties and enhanced photocatalytic activity of ferromagnetic ZrO2 nanostructures on methylene blue dye under ultra-violet radiation

“…They explained that the RTFM is attributed to Zr-related vacancies in the lattice. Thus, the origin of RTFM in ZrO 2 nanostructures has not been addressed properly in previously reported studies [10][11][12][13][14][15] and therefore further investigations are needed to address the origin of RTFM in ZrO 2 nanostructures. Thus, the origin of RTFM in different crystalline phases of ZrO 2 nanostructures is still open for scientific community for further investigations.…”

“…Further, Hong et al [13] reported that the cubic Mn doped ZrO 2 thin films were ferromagnetic at T C above 400 K. The intrinsic ferromagnetism was mainly due to the MnAMn interactions via oxygen intermediates. In an another interesting report, Srivastava et al [14] had reported that no long range ferromagnetic order was observed in Mn doped tetragonal ZrO 2 nanostructures prepared by solid state method. Wang et al [15] had also reported the presence of RTFM in ZrO 2 nanostructures.…”

Adjusting the Magnetic Properties of ZrO2:Mn Nanocrystals by Changing Hydrothermal Synthesis Conditions

“…Clavel et al reported paramagnetic behavior for nanosized ZrO 2 :Mn samples prepared by the benzyl alcohol route [24]. Paramagnetic behavior was reported for polycrystalline Y-stabilized tetragonal zirconia with up to 10% of Mn prepared by the solid state method by equilibrium [25]. For samples doped with higher Mn content (15% and 20% of Mn), local ferrimagnetic ordering was observed due to the Mn 3 O 4 secondary phase.…”

“…For all of the samples, the negative values of the Curie-Weiss temperature θ were determined, which indicates that antiferromagnetic (AF) interactions are predominant in the measured samples. The negative values of the Curie-Weiss temperature have already been reported for ZrO 2 :Mn [14,[23][24][25]. In our paper, we focus on the influence of the synthesis procedure on the resultant magnetic properties, e.g., the Curie-Weiss temperature.…”

Regulation of the magnetic behavior by adjusting oxygen stoichiometry in ZrOx film

“…% Mn. However, Srivastava et al [11] indicated that Y-stabilized zirconia with up to 10% of Mn were found to be paramagnetic, while 15% and 20% Mn-doped show ferromagnetic behavior due to the Mn 2 O 3 secondary phase. Obviously, the field has suffered from the intense controversy on the mechanism of FM.…”