Electrical properties of bulk and nano Li2TiO3 ceramics: A comparative study

Abstract

Nanocrystalline and bulk Li 2 TiO 3 having monoclinic structure were prepared by mechanical alloying as well as conventional ceramic route. Complex impedance analysis in the frequency range of 100 Hz-1 MHz over a wide range of temperature (50-500 ℃) indicates the presence of grain boundary effect along with the bulk contribution. The frequency-dependent conductivity plots exhibit power law dependence, suggesting three types of conduction in the material: low-frequency (100 Hz-1 kHz) conductivity showing long-range translational motion of electrons (frequency independent), mid-frequency (1-10 kHz) conductivity showing short-range hopping of charge carriers and high-frequency (10 kHz-1 MHz) conductivity showing conduction due to localized orientation of hopping mechanism. The electrical conductivity measurement of nanocrystalline and bulk Li 2 TiO 3 with temperature shows the negative temperature coefficient of resistance (NTCR) behavior. The activation energy (0.77 eV for nano sample and 0.88 eV for bulk sample) study shows the conduction mechanism in both samples. The low activation energies of the samples suggest the presence of singly ionized oxygen vacancies in the conduction process.

Transport Properties of Nanostructured Li2TiO3 Anode Material Synthesized by Hydrothermal Method

“…At high frequencies, however, Z (ω) becomes almost temperature independent so that the Z (ω) curves at different temperatures merge approximately in a single curve. This is due to the release of space charges caused by reduction in barrier properties of the material [38]. This unique curve at high frequency shows a dip, which is associated to charge carrier hopping in the material.…”

“…However, β-Li 2 TiO 3 is a wide gap semiconductor with an indirect band gap at Γ-C (E g ≈ 3.9 eV) with low electrical conductivity of 10 −11 S cm −1 at room temperature [35][36][37] and it was considered as a material with electrochemical inactiveness similarly to the rock-salt Li 2 MnO 3 [38]. However, synthesis of nanocrystalline LTO, under the form of nanoparticles, nanorods, nanoflowers and nanofibers, provides more active surface area and shorter diffusion paths for Li + ions in the structure, which makes the material electrochemically active and improves the rate capability [39,40].…”

7313 Published By: Blue Eyes Intelligence Engineering & Sciences Publication Retrieval Number C6011098319/2019©BEIESP DOI: 10.35940/ijrte.C6011.098319 Journal Website: www.ijrte.org Structural, Dielectric and Electrical Properties of Fe Doped La0.7Ba0.3MnO3Solid Solutions for Cathode Materials

“…It is clearly evident that the magnitude of Z′ is high at low temperature and decreases with increase in frequency, which shows a typical negative temperature coefficient of resistance type behavior [18]. The value of Z′ decreases with increase in both temperature and frequency shows the incease in the electrical conductivity [19,20]. Z′ merges in high frequency region at all temperatures showing the reduction of barier properties in the material [21,22].…”

A Comprehensive Study on Li4si1-xtixo4 Ceramics for Advanced Tritium Breeders

“…Neutrons generated from the reaction between deuterium (D) and tritium (T) can react with Li element to produce tritium, thus achieving tritium self-sustaining of a D-T fusion reactor [1][2][3]. With preferable chemical stability, efficient tritium extraction, high temperature resistance and no magnetohydrodynamic effect, lithium-based ceramics have long been recognized as promising TBMs [2,[4][5][6]. However, the overall performance of conventional lithium ceramics (i.e.…”