Details

Autor(en) / Beteiligte

• Anantharamaiah, P. N
• Rao, B. Prerna
• Shashanka, H. M
• Chelvane, J. A
• Khopkar, V
• Sahoo, B

Titel

Role of Mg and In substitution on magnetic, magnetostrictive and dielectric properties of NiFeO ceramics derived from nanopowders

Ist Teil von

• Physical chemistry chemical physics : PCCP, 2021-01, Vol.23 (2), p.1694-175

Erscheinungsjahr

2021

Quelle

Alma/SFX Local Collection

Beschreibungen/Notizen

• The effect of Mg 2+ and In 3+ substitution on the structural, magnetic, magnetostrictive and dielectric properties of NiFe 2 O 4 samples derived through sintering of nanocrystalline ceramic powders is investigated. Namely, NiFe 2 O 4 , NiMg 0.2 Fe 1.8 O 4 and NiIn 0.2 Fe 1.8 O 4 nanopowders were synthesized by a tartrate-gel route followed by calcination at 500 °C, pelletization and sintering at 1200 °C for 2 h. The average particle size was found to decrease from ∼13 nm (for NiFe 2 O 4 ) to ∼9 nm and ∼7 nm for as-synthesized Mg 2+ and In 3+ substituted NiFe 2 O 4 samples (after calcination), respectively. However, after sintering a better grain growth occurs for the In 3+ substituted sample, as confirmed through the microscopy and dielectric results. Due to the replacement of smaller Fe 3+ cations by larger In 3+ and Mg 2+ cations at the tetrahedral (T d ) and octahedral (O h ) interstitial positions, respectively, in the spinel structure of NiFe 2 O 4 , the lattice parameters increase in both the cases. The T d site occupation of In 3+ leads to higher magnetization for the NiIn 0.2 Fe 1.8 O 4 sample, but O h site occupation of Mg 2+ leads to lower magnetization for the NiMg 0.2 Fe 1.8 O 4 sample, in comparison to the pure NiFe 2 O 4 sample. Furthermore, the Curie temperatures ( T C ) and magnetocrystalline anisotropy constants ( K 1 ) for both the samples are considerably lower than the parent compound, with all the parameters being the lowest for the In 3+ substituted sample because the T d occupation of non-magnetic In 3+ drastically decreases the A-O-B magnetic superexchange interactions. The above alteration to the magnetic interactions alters the magnitude of maximum magnetostriction ( λ max ), which is explained based on the occupation of the Mg 2+ and In 3+ cations in our samples. The obtained magnetostriction properties of our samples are very useful for magnetostriction based sensor application. The effect of Mg 2+ and In 3+ substitution on the structural, magnetic, magnetostrictive and dielectric properties of NiFe 2 O 4 samples derived through sintering of nanocrystalline ceramic powders is investigated.