Characterization of structural and electrical properties of Ca0.61Nd0.26TiO3 ceramic tailored by complex ions (Al0.5Nb0.5)4

• Published in: Journal of alloys and compounds Vol. 899; p. 163234
• Main Authors: Xiong, Zhe, Zhang, Xing, Fang, Zixuan, Wu, Wenjuan, Li, Lezhong, Tang, Bin, Zhang, Shuren
• Format: Journal Article
• Language: English
• Published: Lausanne Elsevier B.V 05.04.2022; Elsevier BV
• Subjects: B-site substitution; Ceramics; Dielectric loss; Dielectric properties; Electrical properties; Electrical resistivity; Grain size; Insulation; Microwave dielectric ceramics; Miniaturization; Ordering structure; Permittivity; Perovskite structure; Perovskites; Raman spectra; Structural analysis; Structure-property relation; Transmission electron microscopy; Dielectric loss; Microwave dielectric ceramics; B-site substitution; Ordering structure; Structure-property relation
• ISSN: 0925-8388; 1873-4669
• DOI: 10.1016/j.jallcom.2021.163234

•The Q×f value increased by 60% in (Al0.5Nb0.5)4+-doped Ca0.61Nd0.26TiO3 ceramics.•The right amount of (Al0.5Nb0.5)4+ substitution could restrain the reduction of Ti4+.•The short-range ordering structure contributed to the enhancement of the Q×f value. Miniaturization and low power dissipation are a trend for the development of ceramic-based microwave devices. Therefore, the decrease of the dielectric loss properties of microwave dielectric ceramic material compounds with a high dielectric constant is considered a quite important subject. In this work, the Ca0.61Nd0.26TiO3 material configuration with orthorhombic perovskite structure was thoroughly investigated by applying the strategy of (Al0.5Nb0.5)4+ substitution at the B-site. More specifically, the Ca0.61Nd0.26Ti1-x(Al0.5Nb0.5)xO3 sample with a nearly 60% increase in the quality factor (Q×f) was obtained. Also, the relationship between the structural and the electrical properties of Ca0.61Nd0.26Ti1-x(Al0.5Nb0.5)xO3 (0 ≤ x ≤ 0.15) samples were explored via performing X‐ray diffraction (XRD) measurements, Raman spectra, transmission electron microscopy (TEM) and calculation of the insulation resistance, etc. The extracted outcomes divulged that samples at x = 0–0.12 formed a single perovskite-structured phase, while the grain size of samples decreased by increasing the x value, leading to a drop decline of both the dielectric constant (εr) and electrical conductivity. Additionally, insights from the acquired Raman spectra confirmed that the stressed-rigid oxygen octahedral networks could lower the positive τf value of Ca0.61Nd0.26TiO3-based ceramic compounds. Interestingly, as the doping content of (Al0.5Nb0.5)4+ increased, the Ti3+ in samples was restrained at x = 0.04, whereas the insulation properties of the samples increased. Hence, the conductivity loss was declined. Furthermore, the TEM images illustrated the appearance of a 1: 1 ordered structure at the B-site of the (Al0.5Nb0.5)4+-doped samples. As a result, the Q×f value of the samples raised from 11,095GHz at x = 0–17,802 GHz at x = 0.12, enhanced by 60%. On top of that, for the sample with x = 0.15, the existence of the Ca2Nb2O7 phase deteriorated the microwave dielectric properties of the Ca0.61Nd0.26Ti1-x(Al0.5Nb0.5)xO3 samples, and especially Q×f value.