Polarization-electric Field Hysteresis Loops Research Articles

Machine Learning Based Distinguishing between Ferroelectric and Non‐Ferroelectric Polarization–Electric Field Hysteresis Loops

AbstractThe polarization–electric field (P–E) hysteresis loop is one of the most important criteria for identifying ferroelectricity. However, a P–E loop with apparent hysteresis window can be generated from non‐ferroelectric sources such as leakage current. So far distinguishing between ferroelectric and non‐ferroelectric loops is still performed in a manual way, which can be error prone and time consuming, particularly when the loops are not easily distinguishable and the number of loops to be identified is large. Here, two machine learning (ML) approaches are developed, one using the polarization values along the P–E loops as the input dataset (termed as “value‐based” approach) and the other using the loop images as the input dataset (termed as “image‐based” approach), to identify the P–E loops as ferroelectric or non‐ferroelectric. The value‐ and image‐based ML approaches achieve identification accuracies as high as 93.08% and 87.42%, respectively. In addition, it is tested that both approaches complete an identification of about 160 loops in very short time (≈1.0 s). The high accuracy and efficiency therefore demonstrate that the ML approaches significantly outperform the manual way for distinguishing ferroelectric from non‐ferroelectric P–E loops, which may greatly facilitate the research on ferroelectrics.

High thermally stable dielectric permittivity, polarization enhancement and electrostrictive properties in Zr-substituted bismuth sodium titanate lead-free ferroelectric ceramics

Zr-substituted (Bi0.5Na0.5)(Ti1−xZrx)O3 (BNTZ) with x = 0.02–0.4 ceramics were prepared using solid-state reaction technique and their structural, dielectric and ferroelectric properties were investigated systematically. X-ray diffraction results suggest that Zr4+ ion can enter the (Bi0.5Na0.5)TiO3 (BNT) crystal lattices at a limited value and a secondary phase appears in BNTZ ceramics when the x exceeds 0.1. Temperature-dependent dielectric permittivities of BNTZ ceramics show only one dielectric peak from room temperature to 500 °C for each composition, and this dielectric peak becomes broad gradually as x increases from 0.02 to 0.4. The permittivity of x = 0.4 varies less than ±10% between room temperature and 300 °C, indicating a superior thermal stability of the permittivity. Polarization enhancement is revealed by the polarization-electric field hysteresis loops and highest ferroelectric properties are obtained in x = 0.04. The electric-field-induced strains of x = 0.04 show a monotonous increase as temperature increases from 30 °C to 150 °C. At 80 kV/cm, a high strain level of 0.268% is achieved. Our results suggest that the introduction of Zr4+ ion could effectively tailor the dielectric and ferroelectric properties of BNT ceramics and x = 0.4 composition could find potential application in high temperature capacitor devices.

Structural Tailing and Pyroelectric Energy Harvesting of P(VDF-TrFE) and P(VDF-TrFE-CTFE) Ferroelectric Polymer Blends.

The copolymer P(VDF-TrFE) is a normal ferroelectric because the bulky TrFE monomer improves its crystalline chain structure, while the terpolymer P(VDF-TrFE-CTFE) is a relaxor ferroelectric because the third monomer CTFE makes it amorphous. Herein, in order to induce a crystalline beta phase in the terpolymer, we blended a small amount of crystalline P(VDF-TrFE) into P(VDF-TrFE-CTFE) and investigated the effect of blending on the pyroelectric energy harvesting (PyEH) properties. The polarization-electric field hysteresis loops at different temperatures and energy densities were investigated. The PyEH energy density (ND) is compared with the electrical energy density (UE). The UE and ND at the ferroelectric–paraelectric transition temperature for the χ = 0.1 blend are reported as 3.18 and 5.04 J/cm3, respectively, which are higher than the other polymer blends. Interestingly, the ND of the χ = 0.9 blend is found to be 3.44 J/cm3 when operated at lower and higher temperatures, that is, at TL = 25 °C and TH = 40 °C, respectively, which is the highest possible energy density at the lowest possible transition temperature for the polymer blends.

Fabrication of bimorph lead zirconate titanate thick films on metal substrates via the cold sintering-assisted process

A novel process was developed for the fabrication of 5–50 µm lead zirconate titanate (PZT) thick films on metal substrates. Tape cast PZT with a methyl cellulose binder was burned out at 275 °C, humidified, and then partially densified at 300 °C by cold sintering with a wet lead nitrate liquid phase. Lamination of the green tape on dense metal foils led to incomplete densification due to constrained sintering. However, when metal foils were replaced with tape cast Cu, fully sintered PZT/Cu/PZT composites were acquired after a secondary heat treatment at 800 °C. The PZT films has a relative permittivity over 500 and a loss tangent ~12% at 100 Hz because of a Cu2O interface between the PZT and Cu presumably formed during the cold sintering process. The polarization-electric field hysteresis loop shows a remanent polarization over 20 µC/cm2, and the e31,f of the samples is -4.7 C/m2.

Structural and electrical characterization of hydrothermally deposited piezoelectric (K,Na)(Nb,Ta)O3 thick films

(K0.89Na0.11)(Nb0.85Ta0.15)O3 thick films were epitaxially grown at 200 °C on (001)La:SrTiO3 and (001)cSrRuO3//(001)SrTiO3 substrates by hydrothermal method, and their crystal structures and electrical properties were investigated. Film thickness increased with deposition time and reached 6 µm in 10 h. High-temperature X-ray diffraction measurement showed that successive phase transitions from orthorhombic to tetragonal and from tetragonal to cubic phases take place at 120 and 400 °C, respectively. Microstructure analyses were performed by using electron microscopy, which revealed the existence of two types of stripe patterns with a width of 100 nm or less. In addition, scanning transmission electron microscopy–energy-dispersive X-ray spectroscopy elemental mapping showed that Nb/(Nb + Ta) ratio of the deposited films abruptly changed around 700 nm in thickness. Annealing at 500 °C led to the reduction in leakage current density from 102 to 10–5 A/cm2 at 30 kV/cm, showing that annealing is an effective way to improve insulation. Relative dielectric constant (er) decreased linearly with increasing frequency, reaching 450 at 10 kHz. Polarization–electric field hysteresis loop and field-induced stain curve were measured by piezoelectric force microscopy, which showed remanent polarization (Pr) of 30 µC/cm2 and piezoelectric constant (d33,PFM) of 70 pm/V. These results demonstrate that (K,Na)(Nb,Ta)O3 thick films with superior electrical properties can be fabricated by the low-temperature deposition technique.

Phase transitions and piezoelectricity enhancement around MC → O phase transition in PMN-0.34PT single crystals

Abstract Phase transitions of Pb(Mg1/3Nb2/3)O3-0.34PbTiO3 (PMN-0.34 PT) have been studied by using dielectric constant variations, polarization-electric field hysteresis loops, and polarizing light microscopy (PLM). Even without the assistance of electric field, orthorhombic (O) phase exists in the [001]C-oriented PMN-0.34 PT single crystals during the heating process, which is confirmed by the polarizer/analyzer extinction angle from full-angle in situ PLM observation combined with the grayscale image analysis. The phase transition sequence is monoclinic (MC) → O → MC → tetragonal (T) → cubic (C), which is different from the commonly accepted MC → T → C sequence. The existence of the O phase accompanies with much enhanced dielectric and piezoelectric performance, which indicates a new mechanism to produce large piezoelectricity in PMN-PT single crystals.

Optical and electrical properties of ferroelectric Bi0.5Na0.5TiO3-NiTiO3 semiconductor ceramics

(1-x)Bi0.5Na0.5TiO3-xNiTiO3 semiconducting ferroelectric ceramics (named (1-x)BNT-xNTO) were successfully prepared by using a solid state reaction method. All samples shows normal polarization-electric field hysteresis loops, and a maximum polarization Pmax is obtained in the x = 0.06 composition. The diffuse factor γ decreases slightly from 1.732 to 1.571 with the addition of NiTiO3. In addition, Ni doping can substantially reduce the band gap of Bi0.5Na0.5TiO3 materials to ~2 eV. In a 0.94BNT–0.06NTO compound, the XPS spectra shows that the chemical formula is accurately [Bi0+, Bi3+]0.5Na0.5[Ti3+, Ti4+]O2.25-0.06Ni[Ti3+, Ti4+]O2.67. Moreover, the short-circuit current (Jsc) in the composition is 1.36 nA/cm2, and the open-circuit voltaic (Voc) is 0.35 V for photovoltaic effects. The novel BNT system, which illustrates three narrow band gaps and relatively high polarization values, has broad application prospects for ferroelectric photovoltaic devices.

Evolution of domain structure in PbZr0.52Ti0.48O3 thin film by adding dysprosium

In this study, we improve the thermal stability of PbZr0.52Ti0.48O3 thin film by Dy doping (Dy = 0–4 at.%). The PZT solution is prepared from lead acetate trihydrate, zirconium n-propoxide, and titanium (IV) isopropoxide to have the composition in the morphotropic phase boundary of PbZr(1-x)TixO3 (x = 0.48 at.%); using a spin coater, the solution is then deposited onto a Pt coated Si substrate. The polarization-electric field hysteresis loop shows that the polarization density (μC/cm2) of Dy-doped PZT thin films are enhanced as the amount of Dy increases. Local symmetry study using convergent beam electron diffraction technique then reveals that the Dy doping induces phase transition from P4mm-like to Pm-like symmetry, which has not been found in PZT.

Magnetic and multiferroic properties of dilute Fe-doped BaTiO3 crystals

Combining and coupling both magnetic and electric properties in one single phase multiferroic material has attracted high interest recently to enable a broad range of novel devices and applications. To evaluate one potential route toward new multiferroics, we have studied 0.5% Fe-doped BaTiO3 single crystals and measured the ferroelectric, magnetic, and multiferroic properties. X-ray absorption spectroscopy shows the presence of Fe3+, and magnetic measurements confirmed that this has a significant impact on the magnetic properties. Doping of iron introduces paramagnetism from lone iron atoms as well as what appears to be a weak ferromagnetism. Multiferroicity and magnetoelectric (ME) coupling were observed in the polarization-electric field hysteresis loops with an applied magnetic field, yet there was no direct evidence that ME coupling persists when the sample was in the defect dipole-aligned state.

Effect of L-asparagine as dopant on the growth and characteristics of ammonium tetroxalate dihydrate single crystal

Abstract Single crystals of L-asparagine doped ammonium tetroxalate dihydrate were grown using slow evaporation solution growth technique with deionized water as a solvent. The shift and intensity of the peaks in the single crystal X-ray diffraction and Fourier transform infrared analyses confirmed the inclusion of L-asparagine in the ammonium tetroxalate dihydrate crystal structure. The optical transmission characteristics viz. optical band gap, optical conductivity, etc., were determined. Thermal studies revealed the occurrence of anomalies at 135.3 °C and 221.7 °C leading to the possibility of phase transitions and thereby, ferroelectric behavior. Vickers microhardness studies enabled determination of various microhardness parameters. Dielectric behavior was analyzed by varying the temperature and frequency. Anomalies were observed at 135 °C and 221 °C suggesting the existence of ferroelectric nature of the compound. Self-defocusing effect was observed. The polarization-electric field hysteresis loops showed a pinched effect due to defects induced by inclusion of dopant. The crystals were characterized by single crystal XRD, FT-IR, DRS, UV-Vis-NIR, Vickers microhardness test as well as thermal and dielectric techniques. In brief, L-asparagine as a dopant in ammonium tetroxalate dihydrate altered various physical properties of the crystals. They were highly transparent in the visible region with a wider optical band gap, softer material than the parent, higher phase transition temperature of 135 °C, negative nonlinearity and self-defocusing ability.

Structure, dielectric, and ferroelectric properties of Ba0.85Ca0.15Zr0.1Ti0.9O3 ceramics sintered at various temperatures

The Ba0.85Ca0.15Zr0.1Ti0.9O3 (referred to as BCZT) ceramic powders were synthesized by the sol–gel method followed by calcining, and then the ceramics were obtained by sintering at different temperatures varied from 1200 to 1350 °C. The effects of sintering temperature on the microstructure, impedance spectroscopy, dielectric, and ferroelectric properties for BCZT ceramics have been thoroughly investigated. The pure perovskite structure and homogenous microstructure with high relative density (> 90%) for all BCZT ceramics are identified by XRD analysis and SEM measurement, and the stability is identified by the variable-temperature dielectric characterization. The impedance spectroscopy and well-defined polarization–electric field hysteresis loops for BCZT samples were detected at room temperature. In particular, the BCZT ceramic sintered at 1300 °C resulted the highest dielectric constant (er ~ 2170), the lowest dielectric loss (tan δ ~ 0.027), and the highest grain boundary resistance (Rgb ~ 8.9 × 107 Ω cm).

Understanding the effects of electric-field-induced phase transition and polarization loop behavior on the energy storage performance of antiferroelectric PbZrO3 thin films

Antiferroelectric PbZrO3 (PZO) thin-films were fabricated by pulsed laser deposition (PLD) and sol-gel techniques to investigate the effect of antiferroelectric-ferroelectric (AFE-FE) phase transition on the energy storage performance. The (100)-oriented PLD thin-films have a square-double polarization-electric field (P-E) hysteresis loop with a sharp-phase transition and the (111)-oriented sol-gel thin-films have a slanted P-E loop with a diffused-phase transition. The difference in the phase transition fields between PLD and sol-gel thin-films could be attributed to their difference in crystalline orientations. In this case, the antipolar AFE phase is along the [110]-direction of the original tetragonal-cell under zero electric-field, while the antipolar AFE phase switches into the polar FE phase under a strong enough electric-field and the tetragonal-cell becomes rhombohedral with the polar direction of [111]. Due to the larger maximum polarization and slimmer P-E loop, the higher recoverable energy-storage (Ureco) of 19.4 J/cm3 and larger energy-efficiency (η) of 70.8%, are achieved in sol-gel thin-films. More importantly, this film shows excellent charge-discharge cycling endurance of both Ureco and η values after 1010 cycles and good thermal-stability under a wide operating temperature. From the viewpoint of applications, the sol-gel method is considered to be a promising approach towards producing low-cost PZO thin-films for high-efficiency energy-storage devices over a broad temperature range.

Direct and Indirect Measurement of Large Electrocaloric Effect in B <sub>2</sub>O <sub>3</sub>-ZnO Glass Modified Ba <sub>0.65</sub>Sr <sub>0.35</sub>TiO <sub>3</sub> Bulk Ceramics

Barium strontium titanate (Ba0.65Sr0.35TiO3-BST) added with a 0.5 wt% of B2O3-ZnO glass phase was prepared via a solid-state reaction approach. The lattice structures and morphologies of the ceramics were analyzed using X-ray diffraction and scanning electron microscopy technologies. The dielectric and ferroelectric properties of the glass added BST ceramics were characterized using a precision impedance analyzer and a ferroelectric polarization-electric field (P-E) hysteresis loop tester, respectively. The electrocaloric effect (ECE) was directly measured by a computer controlled thermocouple and high-voltage power supply, and also indirectly calculated using the Maxwell relation and the polarization extracted from the P-E loops as a function of temperature and electric field. The results indicate that when added with 0.5wt% of B2O3-ZnO glass phase, the breakdown electric field of BST ceramic can be increased, and the adiabatic temperature change ΔT was enhanced from 1.70 K to 2.29 K.

Phase field simulation of misfit strain manipulating domain structure and ferroelectric properties in PbZr<sub>(1–<i>x</i>)</sub>Ti<i><sub>x</sub></i>O<sub>3</sub> thin films

Ferroelectric domain structures and ferroelectric properties in the hetero-epitaxially constrained ferroelectric thin films can be manipulated by substrate misfit strain. In this work, three kinds of phase structures of PbZr<sub>(1–<i>x</i>)</sub>Ti<i><sub>x</sub></i>O<sub>3</sub> thin films, including tetragonal, tetragonal- rhombohedral-mixed and rhombohedral phases, are investigated. Firstly, the ferroelectric domain structures at different substrate misfit biaxial strains are obtained by the phase-field simulation. Then we calculate the polarization-electric field hysteresis loops at different misfit strains, and obtain the coercive field, saturation polarization, and remnant polarization. In the tetragonal PbZr<sub>(1–<i>x</i>)</sub>Ti<i><sub>x</sub></i>O<sub>3</sub> (<i>x</i> = 0.8) thin film, compressive strain contributes to the formation of out-of-plane c1/c2 domain, and tensile strain favors in-plane a1/a2 domain formation. With the increase of compressive strain, the tetragonal phase and the rhombohedral phase coexist in PbZr<sub>(1–<i>x</i>)</sub>Ti<i><sub>x</sub></i>O<sub>3</sub> (<i>x</i> = 0.48) film near the morphotropic phase boundary, while the tensile strain reduces the rhombohedral domain size. In the rhombohedral PbZr<sub>(1–<i>x</i>)</sub>Ti<i><sub>x</sub></i>O<sub>3</sub> (<i>x</i> = 0.2) film, the rhombohedral domains are steady states under compressive strain and tensile strain. As the misfit strain changes from –1.0% to 1.0%, the value of the coercive field, saturation polarization and remnant polarization decrease. Among them, for tetragonal-rhombohedral mixed phase, the reductions of saturation field and remnant polarization are larger than for tetragonal phase and rhombohedral phase. The coercive field of mixed phase decreases rapidly under the compressive strain, but deceases slowly under the tensile strain. It is worth noting that the remnant polarization decreases faster than the saturation polarization in three components of ferroelectric thin film. Due to the electromechanical coupling, when <i>x</i> = 0.48 at the morphotropic phase boundary it is shown that the remnant polarization reduction is faster than those of the other two types of ferroelectric thin films, and the small coercive field is obtained in the case of large tensile strain. Therefore, tensile strain can effectively improve the energy storage efficiency in ferroelectric thin films, and the efficiency of <i>x</i> = 0.48 thin film increases significantly compared with that of <i>x</i> = 0.8 or 0.2 thin film. Both the ratio of rhombohedral/tetragonal phase and the domain size will play a significant role in ferroelectric performance. Therefore, our results contribute to the understanding of the electromechanical coupling mechanism of PbZr<sub>(1–<i>x</i>)</sub>Ti<i><sub>x</sub></i>O<sub>3</sub>, and provide guidance for the experimental design of ferroelectric functional thin film materials.

Direct and indirect measurements of the electro-caloric effect in (Bi,Na)TiO3-SrTiO3 ceramics

The electrocaloric effect (ECE) in lead-free (Bi0.5Na0.5)TiO3-SrTiO3 (BNT-ST) ceramics was investigated by direct and indirect measurements. Polarization-electric field hysteresis loops of the BNT-ST ceramics changed from well-saturated shapes at room temperature to constricted shapes around the depolarization temperature due to an electric field-induced phase transition. A large adiabatic temperature change due to ECE (ΔTEC) was obtained around the phase transition temperature (TFR) by indirect measurements, which was confirmed by direct measurements. The 0.85BNT-0.15ST sample showed a large negative ΔTEC in the indirect measurements below TFR where the polarization increases, while the directly measured ΔTEC displayed positive values. It suggests that the indirect method using the Maxwell relation is not valid in the temperature range where the polarization increases with temperature. The X-ray diffraction structural refinements showed that the poled 0.85BNT-0.15ST sample has mixed phases of a rhombohedral R3C and a tetragonal P4bm in the temperature range where the polarization increases below TFR.

Normal/relaxor ferroelectric characteristics of lead-based PZT–PXN ceramics prepared by columbite/wolframite precursors method

The influences of the relaxor ferroelectric modification on dielectric and ferroelectric properties of the normal ferroelectric in (1-y)Pb(Zr1/2 Ti1/2)O3–(y)Pb(X1/3Nb2/3)O3 or (1-y)PZT–(y)PXN systems, with X = Co2+, Ni2+, and Zn2+, and y = 0.1–0.5, using columbite/wolframite precursor method have been investigated. The columbite of CoNb2O6, NiNb2O6, and ZnNb2O6 and wolframite ZrTiO4 were weighed and introduced into the batch calculation. The dielectric constant of the samples showed a maximum dielectric constant at y = 0.2 for all systems, while the transition temperature decreased with increasing relaxor compounds in the system. In addition, the polarization-electric field (P–E) hysteresis loops of the ceramic systems also changed significantly with the relaxor materials content, and reached maximum around y = 0.2–0.3. These results clearly showed the significance of relaxor materials content in controlling the electrical properties of the PZT–PXN ceramic systems. Interestingly, the morphotropic phase boundary (MPB) lied at y = 0.2–0.3 compositions.

Dependence of dielectric and energy storage properties on sintering temperature in lead lanthanum zirconate titanate antiferroelectric ceramics

The effect of sintering temperature on the phase evolution, microstructures, dielectric properties and energy-storage properties of lead lanthanum zirconate titanate antiferroelectric ceramics has been investigated. Scanning electron microscopy images showed that a gradual increase in grain size with increasing sintering temperature. The dielectric measurements revealed that the variation of sintering temperature did not lead to a systematic trend. A correlation between the dielectric properties and microstructures was established. The room temperature dielectric properties demonstrated that both the dielectric constant and saturation polarization increased with increasing sintering temperature up to 1180 °C and then slightly decreased. Furthermore, as for the sintering temperature dependence of energy storage properties, it has shown that with the increase of sintering temperature, both the charged density and discharged density first increased and then decreased. There is an intermediate optimum sintering temperature range (1180 ∼ 1200 °C) in which the samples have better energy storage performance. The dependence of released energy and power densities on the sintering temperature was also investigated. These charge-discharge measurement results were consistent with the calculated values obtained from polarization-electric field hysteresis loops.

A novel method of preparing antiferroelectric silver niobate AgNbO3 ceramics

Lead-free antiferroelectric silver niobate AgNbO3 ceramics have attracted growing interest for their superior energy storage density. The ceramics are commonly prepared by the conventional solid-state reaction method using Ag2O and Nb2O5 as the raw materials. An O2 atmosphere is maintained to prevent the possible decomposition of Ag2O during sintering, which increases the complexity of the process. In this work, we prepared successfully the pure phase AgNbO3 ceramics in air with the hydrothermally synthesized AgNbO3 powders. In comparison with the ceramics prepared by the conventional solid-state reaction method, the ceramics prepared by the hydrothermally synthesized powders have a broader antiferroelectric phase region and show pinched polarization-electric field hysteresis loops at moderate electric fields.

Tuning the electrocaloric effect in 0.94Bi0.5Na0.5TiO3-0.06BaTiO3 ceramics by relaxor phase blending

The pseudo-first-order phase transition in 0.94Bi0.5Na0.5TiO3-0.06BaTiO3 ceramics leads to a sharp increase in temperature change (ΔT) in the vicinity of the ferroelectric-to-relaxor transition temperature TFR (~100 °C) [Appl. Phys. Lett. 110 (2017) 182904]. In this study, we add the 0.78Bi0.5Na0.5TiO3-0.06BaTiO3-0.16(Sr0.7Bi0.2)TiO3 relaxor phase to the 0.94Bi0.5Na0.5TiO3-0.06BaTiO3 ferroelectric matrix to tune its electrocaloric effect. The results show that the addition of the relaxor phase plays a vital role in phase and local-structure evolution. A transition occurs between the ferroelectric and ergodic relaxor phases when the mass fraction of the latter increases to 30% (x = 0.3), as verified by X-ray diffraction analysis, Raman spectroscopy, and polarization-electric field (P-E) hysteresis loops. Furthermore, addition of the relaxor phase reduces the TFR from 76 °C at x = 0.1–55 °C at x = 0.2; however, this transition disappears at x = 0.3 and 0.4 composite. In-situ piezo-force microscopy (PFM) images illustrate that domains can be written into x = 0.1 and 0.2 ceramics with a valley in the piezoresponse curves. Increasing the temperature agitates the domain arrangement and decreases the contrast for PFM images; this indicates a gradual phase transition in the composite. The temperature corresponding to maximum ΔT exhibits a downward shift (0.58 K at 80 °C for x = 0.1 and 0.5 K at 65 °C for x = 0.2), while the temperature-ΔT curves are flat when x = 0.3 and 0.4. Moreover, the maximum ΔT shows a decrease with an increase in the relaxor phase content; this is believed to be related to a decrease in the latent heat due to a pseudo-first-order to second-order transition. Thus, we suggest that the incorporation of a relaxor phase into ferroelectric matrices is an effective technique to tune their electrocaloric effect and improve the thermal stability of ceramic composites.

Bi(Mg0.5Ti0.5)O3-doped NaNbO3 ferroelectric ceramics: Linear regulation of Curie temperature and ultra-high thermally stable dielectric response

Sodium niobate (NaNbO3, NN)-based ferroelectric ceramics have been extensively studied owing to their antiferroelectric (AFE) nature. However, the dielectric properties of NN-based ceramics, which would be beneficial to capacitor devices, gain less research interest. In this study, (1−x)NaNbO3-xBi(Mg0.5Ti0.5)O3 (NN-xBMT, x = 0, 0.01, 0.02, 0.03, 0.04, 0.05) ferroelectric ceramics were manufactured by a traditional solid state method. Structure and dielectric/ferroelectric properties were studied in detail by X-ray diffraction, dielectric spectrum as well as polarization-electric field hysteresis loops. All ceramic samples show an AFE P phase in the doping range. As x increases, the grain size of studied compositions gradually decreases from 5.36 μm in x = 0 to 2.05 μm in x = 0.05. In addition, the incorporation of BMT plays a regulatory role to the Curie temperature TC of ceramic samples, which decreases almost linearly from 375 °C x = 0 to 216 °C x = 0.05 at a rate of 33 °C/1 at. %. However, the degree of diffusion for each composition does not change significantly. More importantly, ultra-high thermally stable dielectric responses in a wide temperature range are obtained in NN-xBMT. Especially in x = 0.03, its permittivity is around 500 at room temperature and shows a variation less than 4.4% from 30 to 150 °C. Our results may have some guiding significance for the preparation of NN-based ceramics with specific TC, and are significantly important for capacitor applications requiring a wide temperature range stability.