The effects of Ba2+ content on depolarization temperature and pyroelectric properties of lead-free 0.94Na0.5Bi0.5TiO3–0.06Ba1+xTiO3 ceramics

Abstract

Lead-free 0.94Na 0.5 Bi 0.5 TiO 3 -0.06Ba 1?x TiO 3 (NBT-0.06B 1?x T) ceramics (0.0 B x B 0.03) were synthesized by a conventional solid-state reaction process. X-ray diffraction shows that the compositions are at the morphotropic phase boundary where rhombohedral and tetragonal phase coexist. Grain size slightly changes with the increase of Ba 2? content and reaches the minimum at x = 0.02. The depolarization temperature (T d ) decreases with the extra Ba 2? content but the lowest T d was obtained at x = 0.01-0.02. The pyroelectric coefficient (p) was measured as a function of Ba 2? content, and increased from 2.90 9 10 -4 to 3.54 9 10 -4 C m -2°C-1 , and from 55.3 9 10 -4 to 740.7 9 10 -4 C m -2°C-1 for x = 0.00 and 0.02 at RT, and depolarization temperature (T d ) respectively. The pyroelectric coefficient (p) shows a large increase with rising the temperature and reaches the maximum value at the depolarization temperature (T d ). The figures of merits of F i , F v and F D have all been improved with the addition of extra barium. These improved pyroelectric properties indicate that NBT-0.06B 1?x T is a promising material for pyroelectric applications or a wide range of temperature.

Enhancement of pyroelectric properties of lead-free 0.94Na0.5Bi0.5TiO3-0.06BaTiO3 ceramics by La doping

“…The coexistence of rhombohedral and tetragonal in NBT-xBT at x = 0.06-0.07 was reported in literature [4,20,22,27] . Therefore, the NBT-0.06BT-xLa phase structure (Sample A-D) is consistent with that reported in literature [15,22,24,28,29] . for the mass transportation.…”

“…of NBT-0.06BT-xLa, 0.0 ≤ x ≤ 1.0 (%) was measured at RT and at 90 °C for Sample A or Td for Samples (B, C, and D). The calculations of FOMs were calculated using Equations (2-6) [4,15,17] :…”

“…°C-1 at Td (87 °C ) [4] . Balakt et al investigated the effects of Ba 2+ content on the pyroelectric properties of NBT-0.06BT ceramics [15] . They found that !…”

“…shows huge enhancement from 55.3 to 740.7 (x10 -4 C.m -2 . °C-1 ) at Td for composition NBT-0.06B1.02TiO3 [15] .…”

Enhanced pyroelectric properties in (Bi0.5Na0.5)TiO3–BiAlO3–NaNbO3 ternary system lead‐free ceramics

“…Moreover, the p of BNT–BT ceramics can be significantly enhanced from 3.15 × 10 −8 to 6.99 × 10 −8 Ccm −2 K −1 through a modulation of Na + /Bi 3+ molar ratio . Doping with elements such as Ba, Mn, and La is another effective way to improve the pyroelectric properties. Recently, a rather high p of 7.42 × 10 −8 Ccm −2 K −1 in BNT–BT ceramics was achieved by Balakt et al through La doping .…”