Charge carrier transport mechanisms in perovskite CdTiO3 fibers

Abstract

Mechanism behind the high thermoelectric power factor of SrTiO3 by calculating the transport coefficients J. Appl. Phys. 113, 053705 (2013); 10.1063/1.4788809Generation-dependent charge carrier transport in Cu(In,Ga)Se2/CdS/ZnO thin-film solar-cells Electrical transport properties of electrospun cadmium titanate (CdTiO 3 ) fibers have been investigated using ac and dc measurements. Air annealing of as spun fibers at 1000 • C yielded the single phase perovskite fibers having diameter ∼600 nm -800 nm. Both the ac and dc electrical measurements were carried out at temperatures from 200 K -420 K. The complex impedance plane plots revealed a single semicircular arc which indicates the interfacial effect due to grain boundaries of fibers. The dielectric properties obey the Maxwell-Wagner theory of interfacial polarization. In dc transport study at low voltages, data show Ohmic like behavior followed by space charge limited current (SCLC) with traps at higher voltages at all temperatures (200 K -420 K). Trap density in our fibers system is N t = 6.27 × 10 17 /cm 3 . Conduction mechanism in the sample is governed by 3-D variable range hopping (VRH) from 200 K -300 K. The localized density of states were found to be N(E F ) = 5.51 × 10 21 eV −1 cm −3 at 2 V. Other VRH parameters such as hopping distance (R hop ) and hopping energy (W hop ) were also calculated. In the high temperature range of 320 K -420 K, conductivity follows the Arrhenius law. The activation energy found at 2 V is 0.10 eV.

Determination of density of states, conduction mechanisms and dielectric properties of nickel disulfide nanoparticles

“…23 The capacitance was estimated by using the relation C = R 1−n n Q 1 n where value of n estimates deviation from ideal Debye behavior, n = 1 for pure capacitor and is zero for pure resistor. 24 The units of Q are Fs…”

Richardson-Schottky transport mechanism in ZnS nanoparticles

“…The slope of the double logarithmic graph directly gives the value of exponent n. The value of exponent n is larger than one (1) and increases with increasing temperature verifying some non-ohmic conduction mechanism in nanoparticles. 21,22 This non ohmic behavior at higher field region indicates that conduction is governed by other processes like Richardson-Schottky (RS) mechanism, Poole Frenkel (PF) mechanism and Space charge limited current (SCLC) mechanism. [21][22][23] To investigate high field conduction mechanism in ZnS nanoparticles, temperature dependent dc transport data has been further evaluated in terms of current density or conductance as a function of applied voltage or applied field.…”

“…21,22 This non ohmic behavior at higher field region indicates that conduction is governed by other processes like Richardson-Schottky (RS) mechanism, Poole Frenkel (PF) mechanism and Space charge limited current (SCLC) mechanism. [21][22][23] To investigate high field conduction mechanism in ZnS nanoparticles, temperature dependent dc transport data has been further evaluated in terms of current density or conductance as a function of applied voltage or applied field. 31,32 The graph between logarithmic conductance (G) and square root of the applied voltage (V) has been plotted as shown in Fig.…”

“…[20][21][22][23][24][25] The detailed study of DC conduction mechanism in ZnS nanoparticles is still lacking in literature because no comprehensive report has been found so far. For synthesis of cubic ZnS nanoparticles, there exist several techniques such as solvo thermal method, hydrothermal method, solid state reaction method, sol-gel processing and chemical co-precipitation method.…”

An Investigation of Ac Impedance and Dielectric Spectroscopic Properties of Conducting Chitosan-silane Crosslinked-poly (Vinyl Alcohol) Blended Films

“…The circuit consists of one RC loop connected in series whereas CPE 1 represents the constant phase element which was used to accommodate the non-ideal capacitor behavior. In addition CPE 2 was used to model the electrode effect at all temperatures 34 . The capacitance (C) was calculated using the expression: Where, n is empirical constant represents, the deviation from ideal Debaye behavior and its value is 0 < n < 1 [35] .…”