Superlinear dependence of the conductivity, double/single Jonscher variations and the contribution of various conduction mechanisms in transport properties of La0.5Ca0.2Ag0.3MnO3 manganite

Structural, morphological, and electrical properties of silver-substituted ZnAl2O4nanoparticles

“…In addition, it was confirmed by Moualhi et al that the presence of silver leads to the coexistence of multiple conduction mechanisms in the same material. 19–21 In the present work, it was confirmed that increasing the rate of silver element enhance the quality of surface of the studied system, which induces the diminution of the number of the resistive barriers. This implies the diminution of the activation energy value by increasing the rate of the silver element.…”

“…In the literature, various experimental instigations conrm that the substitution by silver element affects the physical properties of the materials. [19][20][21] Accordingly, it is found that the presence of silver permits the activation of tunneling conduction processes. In addition, it was conrmed by Moualhi et al that the presence of silver leads to the coexistence of multiple conduction mechanisms in the same material.…”

“…[14][15][16] In recent years, nanocrystalline materials like ZnAl 2 O 4 spinels have attracted considerable interest in the eld of catalysis because they can be used as carriers of noble metals to substitute for more traditional materials. 17,18 Typically, the use of silver as a doped element improves the electrical inhomogeneity on the grain and the surface microstructure, [19][20][21] and catalytic activities. Additionally, when the highly conductive metal Ag provides a conduction path between the grains, the resistivity of the spinel will be reduced, greatly improving the activity, selectivity, recycling, and reproducibility of catalytic systems, making the material useful for potential of application.…”

Fundamental Behaviors, and Contributions of Hopping and Tunneling Mechanisms to the Transport Characteristics of the La0.5Ca0.5MnO3 Phase Separated Perovskite

“…Figure (a–e) shows the conductivity spectra for the half-doped La 0.5 Ca 0.5 MnO 3 compound at various temperature ranges. Various approaches were proposed to analyze the electrical conductivity spectra for many materials classes. − Bruce and Jonscher’s power laws were extensively exploited to investigate the electrical conductivity response of manganites. ,, In addition, the superlinear power law (SPL) and the nearly constant loss were used to comprehend the dynamics of the charge carriers and to analyze the strong frequency dependence of the conductivity within the oxide structures. ,− At low temperatures, the reported results suggest that each spectrum can be divided into three frequency ranges. For each frequency range, the conductivity variation obeys a specific law.…”

“…In oxide materials, the semiconductor behavior is often described by the significant involvement of different conduction processes. ,− Based on the Mott studies, − the semiconductor character of the materials correlates with the contribution of the small polaron hopping (SPH) mechanism at high temperatures. The variable range hopping (VRH) model was proposed to describe the electrical response of materials below T = θ D /2 (θ D defines the Debye temperature). − Experimentally, the Debye temperature can be estimated from the evolution of ln­(σ dc T) versus 1/(k B T), at high temperatures, where the deviation from linearity gives θ D /2.…”