Temperature dependent conductivity mechanisms observed in Pr2NiTiO6

Abstract

The crossover between two different conduction mechanisms (variable range and small polaron hoppings) is probed utilizing a conjunction of thermally varying conductivity and impedance in polycrystalline Pr2NiTiO6 (PNT). A combination of X-ray diffraction (XRD) and Raman spectroscopic investigations authenticates the lower symmetric monoclinic structure for PNT. The conductivity, impedance and relaxation spectra highlight the combined contributions of the electrodes, grain-boundaries and grain microstructures to the carrier dynamics in PNT. The relaxation mechanism has a non-ideal nature with distribution of relaxation times as observed from the dielectric and impedance spectroscopic revelations. The dc resistivity investigation points towards a transition in the conduction mechanism showing a gradual crossover at temperature 490 K, from small polaron hopping to Mott's variable range hopping due to reduced activation energy.

Existence of nearest-neighbor and variable range hopping in Pr2ZnMnO6 oxygen-intercalated pseudocapacitor electrode

“…With the increasing frequency, after a certain value of frequency, the dipoles lag behind the applied field and do not respond with the field, resulting in a sudden drop in the value of ε'. The maximum value of tanδ is around 0.4 -0.5 for GBs and 0.2 -0.25 for Gs, as described by other researchers [20,42].…”

“…To determine the hopping model involved in the system, we plotted the 𝜎 𝑑𝑐 values against the inverse of temperature (10 3 /T) in the inset of Figure 9(b). The linear trend of the curve indicates the activation of the nearest neighbor hopping model at high-temperature regions [61,62]. The activation energy value was calculated as 0.308 eV using Equation 8.…”

“…This type of carrier dynamics basically occurs at correspondingly low temperatures. However, some literature [20] reported that VRH can also occur at and above room temperature.…”

Structural, magnetic and magnetocaloric properties in distorted RE 2NiTiO6 double perovskite compounds

“…Based on this background, we found that the RE 2 NiTiO 6 compounds containing light RE ions have unique properties in the areas of optics, electricity and magnetism through the results of the relevant literatures [37][38][39]. However, there are few reports on the RE 2 NiTiO 6 compounds containing heavy RE ions to date, especially in term of the magnetic and MCE properties.…”

Dielectric, AC Conductivity, and DC Conductivity Behaviours of Sr2CaTeO6 Double Perovskite

“…Mechanisms that are commonly utilised to elucidate the AC conductivity properties of perovskites related to the variation in s at different temperatures. For instance, variable range hopping (VRH), small polaron hopping (SPH), quantum mechanical tunnelling (QMT), non-overlapping small polaron tunnelling (NSPT), and overlapping large polaron tunnelling (OLPT) mechanisms [18,[41][42][43][44][45][46]. According to the pattern in Figure 8b, a variation in s values from 298 K to 323 K could be linked to NSPT or SPH.…”