The Comparison between Samarium Doped Nickel Oxide and Samarium Added Nickel Oxide on Dielectric Properties

Abstract

In this research, the effect of Samarium Oxide (Sm) doped (mol%) NiO as a dopant and added (wt%) in NiO as ceramic composite were investigated. The comparison of both doped and added ceramic in their dielectric properties was studied. Both electroceramic Ni(1-x)SmxO and NiSmO3 were prepared by using a solid-state reaction method. Samarium was added with five different concentrations, which are 0.01, 0.02, 0.03, 0.05, and 0.10 mol% for dopant and another five different concentrations which are 1, 2, 3, 4, and 5 wt% for addition in NiO. The XRD results show that both ceramic doped and added samples did not change the NiO cubic structure. Besides, a high concentration of Sm3+ causes the lattice parameter of NiO to increase. The dielectric behavior was observed in a frequency range of 100 to 100 000 Hz. The optimum composition for Ni(1-x)SmxO and NiSmO3 was obtained at × = 0.01 mol% and 5.0 wt% sample with highest ε° (2.4 × 104 and 9.3 × 104) respectively but at the same time, they exhibit high dielectric loss (tan δ) with value 4.9 and 10.5 respectively.

Sm-Doped NiO Nanoparticles for Magnetic Memory at Room Temperature

“…A slight lattice expansion from 4.17671(4) to 4.17743(4) Å is evident with increase of the Sm content from 0 to 0.5%, above which a slight contraction with a value close to ∼4.177 Å occurs. The obtained slight lattice expansion agrees with the previous report; however, we did not see any peak splitting (Figure b) . Contrary to the above observation, a contraction has also been reported from Ni 98 Sm 2 O NPs. , The ionic radius of Sm 3+ (109.8 pm) is much larger than that of Ni 2+ (83 pm), which justifies the obtained lattice expansion and suggests that Sm-doping up to 0.5–1% possibly leads to substitution of Ni 2+ ions with Sm 3+ .…”

“…The variation in the ⟨ d XRD ⟩ and η concerning Sm content is also supported by the reduced intensity of the PXRD diffractogram and the obtained ⟨ d ⟩ from FE-SEM. The above findings assert that Sm has very low solid solubility (up to 1%) in NiO; its incorporation significantly disturbs the NiO lattice structure and hinders its crystal growth, possibly through surface charge modification. ,, …”

“…Contrary to the above observation, a contraction has also been reported from Ni 98 Sm 2 O NPs. , The ionic radius of Sm 3+ (109.8 pm) is much larger than that of Ni 2+ (83 pm), which justifies the obtained lattice expansion and suggests that Sm-doping up to 0.5–1% possibly leads to substitution of Ni 2+ ions with Sm 3+ . The above finding is consistent with the observed very weak diffraction peak (marked with “*”) of the Sm 2 O 3 phase for the 2–5% samples . The formation of the Sm 2 O 3 phase can be attributed to the Sm 3+ content exceeding a percolation threshold for the incorporation into the cubic lattice.…”

“…The formation of the Sm 2 O 3 phase can be attributed to the Sm 3+ content exceeding a percolation threshold for the incorporation into the cubic lattice. At and above 2%, instead of occupying the Ni 2+ sites in the lattice, Sm 3+ ions form a more stable secondary Sm 2 O 3 phase, possibly aggregating around the grain boundary. ,, From the above discussion, we expect that the substitution of much bigger Sm 3+ ions at the Ni 2+ lattice sites produces lattice strain, altering the metal-oxide polyhedra, and leads to a decline in the crystallinity (i.e., size) of the material.…”

“…Recently, the rare earth (RE)-doped TMO has attracted immense research interest from both fundamental and application points of view as a dielectric, for biomedical near-infrared and magnetic resonance imaging, optoelectronics, and magnetic, optical, and electrical properties. − RE elements are known to significantly improve the host material’s electrical and magnetic properties if doped at an appropriate concentration. This is due to incompletely filled 4f orbits shielded by 5s 2 and 5p 6 orbits, large ionic radii that cause a lattice distortion, change in the ionic state, and reduced crystalline size of the host sample .…”