In this research paper,we utilized the traditional high-temperature solid-state reaction method to fabricate the K_(0.495)Na_(0.520)NbO_(3),K_(0.480)Na_(0.535)NbO_(3)and K_(0.475)Na_(0.540)NbO_(3)(abbreviated as KNN-1...In this research paper,we utilized the traditional high-temperature solid-state reaction method to fabricate the K_(0.495)Na_(0.520)NbO_(3),K_(0.480)Na_(0.535)NbO_(3)and K_(0.475)Na_(0.540)NbO_(3)(abbreviated as KNN-1,KNN-2,and KNN-3,respectively)lead-free ion deficient ceramics for understanding the influence of ionic deficiency on the crystalline structure and dielectric/piezoelectric properties of the samples.X-ray diffraction patterns of these samples exhibited a perovskite tetragonal phase.Dielectric anomalies around 287℃and 471℃were identified as ferroelectric to ferroelectric and ferroelectric to paraelectric-transition temperatures for KNN-2 at 1 kHz.It was found that the composition KNN-2 exhibit relatively high Curie temperature i.e.,471℃.The conductivity plots confirm that the activation energies are frequency-dependent.The impedance behavior in our ceramic samples can be analyzed with the bulk/grain effect.The slope of Z′with temperature shows negative temperature coefficient of resistance(NTCR)type behavior in proposed KNN ceramics material.展开更多
基金the DST(INT/RUS/RFBR/P-299)New DelhiRFBR(#17-58-45026 IND_a)Moscow for financial support.
文摘In this research paper,we utilized the traditional high-temperature solid-state reaction method to fabricate the K_(0.495)Na_(0.520)NbO_(3),K_(0.480)Na_(0.535)NbO_(3)and K_(0.475)Na_(0.540)NbO_(3)(abbreviated as KNN-1,KNN-2,and KNN-3,respectively)lead-free ion deficient ceramics for understanding the influence of ionic deficiency on the crystalline structure and dielectric/piezoelectric properties of the samples.X-ray diffraction patterns of these samples exhibited a perovskite tetragonal phase.Dielectric anomalies around 287℃and 471℃were identified as ferroelectric to ferroelectric and ferroelectric to paraelectric-transition temperatures for KNN-2 at 1 kHz.It was found that the composition KNN-2 exhibit relatively high Curie temperature i.e.,471℃.The conductivity plots confirm that the activation energies are frequency-dependent.The impedance behavior in our ceramic samples can be analyzed with the bulk/grain effect.The slope of Z′with temperature shows negative temperature coefficient of resistance(NTCR)type behavior in proposed KNN ceramics material.
