Electrical transport in lead-free (Na_0.5Bi_0.5)_1–xSr_xTiO₃ ceramics (x = 0, 0.01 and 0.02)

ABSTRACT

Lead-free (Na_0.5Bi_0.5)_1xSr_xTiO₃ (x = 0, 0.01 and 0.02) ceramics were manufactured through a solid-state mixed oxide method and their ac (σ_ac) and dc (σ_dc) electric conductivity were studied. It is shown that the low-frequency (100 Hz–1 MHz) ac conductivity obeys a power law σ_ac ∼ ω^s characteristic for disordered materials. Both the dc and ac conductivities have thermally activated character and possess linear parts with different activation energies. The calculated activation energies are attributed to different mechanism of conductivity. Frequency dependence of σ_dc and exponent s is reasonably interpreted by a correlated barrier hopping model. The NBT-ST system is expected to be a new promising candidate for lead-free electronic materials.

KEYWORDS:

• NBT-ST
• electrical properties
• hopping
• charge carriers transport

Disclosure statement

No potential conflict of interest was reported by the authors.