Abstract

The effect of NiO doping (0–0.8 wt%) on the phase structure, microstructure, dielectric and magnetic properties of 0.99(K_0.45Na_0.52Li_0.03)(Nb_0.94Sb_0.06)O₃-0.01BiScO₃ (KNLNS-BS) ceramics was investigated. The samples were fabricated by the solid-state combustion technique with glycine used as fuel. Powders and ceramics were calcined and sintered at temperatures of 700 °C for 1 h and 1120 °C for 3 h, respectively. The phase formation from the XRD results showed a pure perovskite structure with coexisting rhombohedral and tetragonal phases in all samples. The ratio of the rhombohedral and tetragonal phases (R:T) of the 0.6 wt% NiO doped sample was 40:60, as verified by the Rietveld refinement technique. The grain morphology of the ceramics exhibited irregular polyhedron shapes and the average grain size was in the range of 1.3 ± 0.15 to 2.6 ± 0.51 µm. KNLNS-BS ceramics with 0.6 wt% added NiO had the highest density (4.40 g/cm³) and the highest maximum dielectric constant (ε_C = 5013). Without NiO doping, the ceramic showed diamagnetic behavior, whereas all of the NiO-doped ceramics exhibited paramagnetic behavior measured at a temperature of 50 K.

摘要

NiO掺杂（0–0.8 wt％）对0.99（K _0.45 Na _0.52 Li _0.03）（Nb _0.94 Sb _0.06）O ₃ -0.01BiScO ₃的相结构，微结构，介电和磁性能的影响研究了（KNLNS-BS）陶瓷。通过固态燃烧技术以甘氨酸为燃料制备样品。将粉末和陶瓷分别在700°C的温度下煅烧和烧结1 h，在1120°C的温度下烧结3 h。X射线衍射结果表明，在所有样品中钙钛矿结构均具有菱形和四方相共存。经Rietveld精炼技术验证，掺入0.6 wt％NiO的样品的菱形和四方相之比（R：T）为40:60。陶瓷的晶粒形态表现出不规则的多面体形状，并且平均晶粒尺寸在1.3±0.15至2.6±0.51μm的范围内。添加了0.6 wt％NiO的KNLNS-BS陶瓷具有最高的密度（4.40 g / cm ³）和最高的最大介电常数（ε）_C = 5013）。如果不掺杂NiO，则陶瓷表现出抗磁性能，而所有掺杂NiO的陶瓷都表现出在50 K温度下测得的顺磁性能。