The Korean Society of Surface Science and Engineering

Owing to its distinctive and valuable physical properties, lead scandium niobate (Pb(Sc_1/2Nb_1/2)O₃) has continued to attract significant research interest across various scientific disciplines, despite its limited environmental compatibility. In the present study, the structural characteristics and physical properties—including ferroelectric behavior—of disordered Pb(Sc_1/2Nb_1/2)O₃ ceramics synthesized at temperatures ranging from 1320℃ to 1380℃ were systematically examined. Among the synthesized samples, the specimen sintered at 1350℃ for 2 hours exhibited the most complete perovskite singlephase structure. Under these optimized conditions, a broad relaxation phenomenon associated with space-charge and dipolar interactions was observed across a wide temperature range. The corresponding dielectric constant and dielectric loss were approximately 36,720 and 0.039, respectively. The complex admittance of Pb(Sc_1/2Nb_1/2)O₃ was measured as the temperature was increased in 30℃ increments from room temperature, enabling detailed analysis of its frequency-dependent electrical response. The results indicate that the frequency response is strongly correlated with the polarization mechanism and energy dissipation processes intrinsic to ferroelectric materials. Furthermore, Pb(Sc_1/2Nb_1/2)O₃ exhibited a pronounced frequency dependence within the phase transition region and evident thermal hysteresis between heating and cooling cycles. The critical exponents derived from the heating and cooling experiments were 1.15 and 1.58, respectively, confirming the material’s diffuse phase transition behavior.

키워드 Pb(Sc_1/2Nb_1/2)O₃; Frequency dependence; Complex admittance; Dielectric relaxation.