Small polaron conduction in lead modified lanthanum ferrite ceramics

Investigation on electrical conductivity and dielectric property of La0.8Pb0.2(Fe,Ti)0.5O3ceramic nanoparticles

“…Lanthanum orthoferrites (LaFeO 3 Þ are an attractive class of research materials because of their comprehensive physical properties and application in advanced technology. [1][2][3] Modification of their structure has been shown to play an important role in the optimization of their structural, optical and electrical properties. [2][3][4][5] In this context, cation substitution has been reported to produce cation displacement, which in turn contributes to the structural changes that result in the generation of dielectric dipoles.…”

“…[1][2][3] Modification of their structure has been shown to play an important role in the optimization of their structural, optical and electrical properties. [2][3][4][5] In this context, cation substitution has been reported to produce cation displacement, which in turn contributes to the structural changes that result in the generation of dielectric dipoles. [1][2][3][4] Thus, Ti-substitution on the Fe site of LaFeO 3 introduced weak ferromagnetic ordering correlated with the 3d 0 valence electron of Ti-ions, resulting in a dielectric constant in the range of $ 10 3 .…”

“…[2][3][4][5] In this context, cation substitution has been reported to produce cation displacement, which in turn contributes to the structural changes that result in the generation of dielectric dipoles. [1][2][3][4] Thus, Ti-substitution on the Fe site of LaFeO 3 introduced weak ferromagnetic ordering correlated with the 3d 0 valence electron of Ti-ions, resulting in a dielectric constant in the range of $ 10 3 . 2 Pb-substitution on the La site of La 1Àx Pb x FeO 3 demonstrated typical colossal dielectric constant (higher than 10 4 ) behavior for x > 0:1 in the temperature range of 300-450 K, and the highest dielectric constant was found to be $ 30:000 for the sample with x ¼ 0:2.…”

“…2 Pb-substitution on the La site of La 1Àx Pb x FeO 3 demonstrated typical colossal dielectric constant (higher than 10 4 ) behavior for x > 0:1 in the temperature range of 300-450 K, and the highest dielectric constant was found to be $ 30:000 for the sample with x ¼ 0:2. 3,4 Moreover, the presence of a hopping polaron as the charge carrier was detected in the relaxation and conduction process. 3 Motivated by the magnetic ordering and high dielectric constant introduced by Ti-and Pb-substitution, we decided to modify LaFeO 3 by simultaneously substituting the La and Fe sites with Ti-and Pb-ions.…”

“…3,4 Moreover, the presence of a hopping polaron as the charge carrier was detected in the relaxation and conduction process. 3 Motivated by the magnetic ordering and high dielectric constant introduced by Ti-and Pb-substitution, we decided to modify LaFeO 3 by simultaneously substituting the La and Fe sites with Ti-and Pb-ions. The resulting La 0:8 Pb 0:2 (Fe, Ti) 0:5 O 3 (LPFTO) material was synthesized by sol-gel and sintering methods.…”