Electron-pinned Defect-dipoles Research Articles

Mechanisms of enhanced performance in Zr4+/Ta5+ codoped rutile-TiO2 ceramics via broadband dielectric spectroscopy.

Aliovalent dopant codoped rutile-TiO2 materials have garnered attention due to their excellent performance properties, characterized by low loss tangent (tanδ), high dielectric permittivity (ε'), and stable ε' over a broad temperature range. This performance is primarily due to the electron-pinned defect-dipoles (EPDDs) of the complex defects [Formula: see text]Ti3+-[Formula: see text]Ti3+BTi. Notably, the excellent dielectric properties in ZrxTa2.5%Ti0.975-xO2 (Zr-TTO) ceramics can be achieved using the traditional mixed oxide method without the EPDDs, due to the absence of A3+ (acceptor doping ions). Instead, the existence of localized free electrons and oxygen vacancies ([Formula: see text]) in Zr-TTO structures, due to doping ions and the sintering process, was confirmed by X-ray photoelectron and Raman spectroscopies. These ceramics exhibited ε'~ 2 × 104 and tanδ < 0.03 at 1kHz and 25°C in the 2.5-10%Zr-TTO samples. Moreover, all ceramics demonstrated a maximum ε' change (∆ε') of less than ±15% over the temperature range suitable for X7R and X8R type ceramic capacitors. Significantly, the change in ε' related to relative humility was calculated to be less than ±0.5% over the range of 50-95% RH, indicating the environmental stability of the dielectric properties, which is essential for capacitor applications. Investigations suggested that at least four mechanisms contributed to this system: the intrinsic effect of ionic polarization, Ti4+ · e- -[Formula: see text]- Ti4+ · e- and Ti4+ · e- - [Formula: see text] defects, interfacial polarization at insulating grain boundaries, and non-Ohmic contact between the surface sample and the metal electrode.

Giant dielectric properties and temperature stability of triple–doped AlxIn0.05−xTa0.05Ti0.9O2 ceramics

AlxIn0.05−xTa0.05Ti0.9O2 ceramics with x ranging from 0 to 0.05 were synthesized using a conventional solid–state reaction method. All samples achieved a pure rutile–TiO2 phase. Additionally, the lattice parameters of the samples increased with higher Al doping concentrations. The ceramics exhibited a dense microstructure and uniform dispersion of dopants. Raman spectroscopy revealed a decrease in oxygen vacancies in the structure with increasing Al3+ concentration. The presence of Ti3+ in the structure was confirmed by X–ray photoelectron spectroscopy. The dielectric properties of all samples were investigated as functions of frequency and temperature. The triple–doped AITTO ceramics demonstrated a high dielectric constant (ε′) of ∼2×104 and low dielectric loss (tanδ) ranging from 0.029 to 0.04, along with excellent temperature stability of ε′ at 1 kHz, showing a Δε′/ε′30 of less than ±15% over a temperature range of −60 to 210 °C. Notably, the tanδ of the triple–doped AITTO ceramics remained below 0.04 even at 200 °C. Impedance spectroscopy was utilized to analyze the electrical properties of the grains and grain boundaries. The observed dielectric properties are attributed to the formation of electron–pinned defect–dipoles, along with the impacts of both internal and surface barrier layer capacitors.

Colossal permittivity and excellent temperature stability of BaTiO3 based fine ceramics with controlled grain growth

Dielectric materials with colossal permittivity (CP, εr > 104) have attracted the increasing interest of researchers due to their enormous potential in the fields of sensor, capacitor, energy storage, etc. However, for the explored CP materials, their grains are too large to apply. To control grain growth, the sintering aids of MgO–Al2O3–SiO2 (MAS) cordierite glass and common suppression grain growth of MgO have been introduced to BaTiO3-0.004Y2O3-0.006MnO2 ceramics derived from the commercial BaTiO3 powder with the average grain size of 300 nm. After controlling grain growth, the fine grains with the average grain size of dg ∼300 nm and CP are achieved in BaTiO3 based ceramics sintered in reducing atmosphere. Notably, excellent temperature stability with Δεr/εr25°C lower than 17 % is gained for the present BaTiO3 based ceramics in the temperature range of −60 to 155 °C, meeting the X8S specification (ΔC/C25°C ≤±22 %, −55 °C–150 °C). Based on the X-ray photoelectron spectroscopy (XPS) and Raman spectra, the outstanding dielectric properties of the present BaTiO3 based ceramics is ascribed to the electron-pinned defect-dipole (EPDD) effect induced by YTi′−YBa∙, TiTi′−Vo∙∙−TiTi′ and YTi′−Vo∙∙−TiTi′ defect dipoles. The present BaTiO3 based fine ceramics with colossal permittivity (∼2.9 × 104), low loss (∼0.03) at 1 kHz and room temperature, excellent temperature stability and high resistivity of 3.54 × 109 Ω cm is a promising candidate for the multilayer ceramics capacitor (MLCC).

Experimental and theoretical investigations on the lattice defects and sintering atmosphere tuning the colossal permittivity of SrTiO3 ceramics

The Sr0.995La0.005TiO3 ceramics were fabricated with traditional solid-state methods under diverse sintering atmospheres. The dielectric properties have a significant correlation with the sintering atmosphere, while showing favorable temperature and frequency stability. As sintered in a mixed hydrogen-nitrogen atmosphere, Sr0.995La0.005TiO3 ceramics exhibited a colossal permittivity (ԑr ∼ 31307), low dielectric loss (tanδ ∼ 0.038) and good frequency stability synergistic temperature stability (−70 °C-180 °C, ΔC/C25°C ≤ ±15 %). The association mechanism of oxygen vacancies, lattice defects, and dielectric characteristics is evaluated in the context of experiments and first-principles. The phase structure and microstructure analysis revealed that the ceramics contained a two-phase structure with a SrTiO3 phase and a TiO2 second phase. The analysis of elemental valence and dielectric characterization demonstrated that defective dipoles, oxygen vacancies, and defect clusters resulting from non-homogeneous ion substitution are the major reasons for contributing to the colossal permittivity and low dielectric loss of the ceramics. This revealed that the electron-pinned defect dipole (EPDD) effect dominates in Sr0.995La0.005TiO3 ceramics. In addition, it can be established that the SrTiO3 phase and TiO2 phase contribute to the EPDD effect simultaneously, with SrTiO3 main phase taking the main role. According to the ELF plot analysis, when the content of oxygen vacancies is high, electrons accumulate at oxygen vacancies and defect clusters, leading to a high localization of electrons, which contributes to colossal permittivity and low dielectric loss of ceramics. The results are promising in colossal permittivity (CP) materials.

X9R-type SrTiO3 based ceramics with colossal dielectric permittivity and low loss derived from defect engineering and high-energy ball milling

The miniaturization of electronic components has become a megatrend in the future, making colossal dielectric permittivity materials receive unprecedented attention. In this work, we proposed a universal route to achieve colossal dielectric permittivity, low loss factor and excellent dielectric temperature stability in rare earth doped perovskite oxide SrTiO3. Sm doped SrTiO3 ceramics prepared by high-energy ball milling exhibit ultrahigh dielectric permittivity 441,543, low loss factor 0.02, good dielectric temperature stability (<15 %) in the temperature range of −55–200 °C, and very high resistance 109Ω, which meets the EIA X9R standard, XPS and impedance spectra indicate that the electron-pinned defect-dipoles effect is the origin of colossal dielectric permittivity and low loss factor. This work shows that Sm-doped SrTiO3 activated by high-energy ball milling has broad prospects in the applications of thermally-stable miniaturized capacitors.

Enhanced dielectric properties and improved thermal stability in TiO2-based ceramics by Cu and Nb co-doping

TiO2-based ceramics have application potential in multilayer ceramic capacitors because of its large dielectric constant and low dielectric loss. In this work, Cu2+, Nb5+ co-doped TiO2 ceramics (CNTO) with colossal permittivity and low loss were designed and prepared via an oxide mixed method, and the effect of Cu2+, Nb5+ co-doped amount on dielectric properties were systematically investigated. Remarkably, the compositions of (Cu1/3Nb2/3)0.005Ti0.995O2 and (Cu1/3Nb2/3)0.01Ti0.99O2 exhibit large dielectric permittivity (εr) of ∼27,060 and ∼41,200 accompanied with low dielectric loss (tan δ) of ∼0.011 and ∼0.032 at 1 kHz, respectively. Based on dielectric properties, relaxation behavior assessments and X-ray photoelectron spectroscopy analysis, we confirmed that the high dielectric permittivity of CNTO ceramics mainly originates from the electron-pinned defect-dipole (EPDD) effect. Moreover, the temperature stability value of εr keeps stable of ±7.5% at 1 kHz from −200 to 200 °C for (Cu1/3Nb2/3)0.005Ti0.995O2 and from 10 to 200 °C for (Cu1/3Nb2/3)0.01Ti0.99O2 ceramics, which separately meet the X9F and Z9F capacitor requirements, respectively. The findings presented in this work might have important strategic significance for promoting the miniaturization of electronic components.

Effect of different defects on the polarization mechanism of (Nb,Ga) codoped TiO2 single crystals

Various defects have a profound impact on the dielectric properties and polarization mechanisms of (Nb,Ga) codoped TiO2 crystals. However, the research conducted in this area remains limited. To address this, we grew (Nb,Ga) codoped TiO2 crystals via the Verneuil method and investigated their dielectric properties under various atmospheric annealing conditions. Annealing in oxygen reduces the number of defects. In this case, the point defects associated with oxygen vacancies is unable to fully form the ideal complex defect clusters which can form effective pegging of free electrons. On the other hand, the defects are mainly in the form of simple defect clusters that causes hopping polarization. Annealing under mixed gas (Ar:H2 = 95%:5%) increases the number of defects and contains more free carriers, which migrate to the interface between the sample and the electrode, leading to interfacial polarization. Both hopping polarization and interfacial polarization are slow polarization, resulting in an increase in dielectric loss and a decrease in frequency stability. Annealing in air or nitrogen atmospheres forms ideal defect dipole clusters, where the electron-pinned defect dipoles (EPDD) are predominantly polarized, resulting in superior dielectric properties. It has been clarified that EPDD as the main polarization form can yield better dielectric properties. By focusing on single crystals as the research subject, we effectively eliminate the influence of grain boundaries, enabling a more accurate assessment of the effects of various crystal defects on dielectric properties. This study holds substantial implications for the advancement of TiO2-based dielectric materials, offering valuable insights into their performance optimization.

Large permittivity, low loss and defect structure in (Nb, Zn) co-doped SnO2 ceramics studied through a combined experimental and DFT calculational method

Dielectric ceramics with high permittivity and low loss are widely used in electronic components and devices. In this study, (Nb, Zn) co-doped NbxZnySn1-x-yO2 with different doping levels and Nb/Zn ratios was designed to tune the defect structure toward the optimal dielectric performance. The lattice parameters firstly increased from x = y = 0.01 to 0.03 and then decreased, while the oxygen vacancy concentration decreased with doping. The co-doped sample with x = y = 0.02 exhibits stable permittivity up to 800 with an ultra-low loss tanδ ∼0.03 at 40 Hz. DFT calculation showed that the oxygen vacancy was formed with single-Zn doping and co-doping at low doping level, while the hole was generated at higher doping level. The achieved large permittivity and low loss of the sample are related to both Electron-Pinned Defect Dipoles (EPDD) and Hole-Pinned Defect Dipoles (HPDD) effects in the lattice, which was determined by the relative positions of donor and acceptor dopants.

Synthesis and Dielectric Relaxation Studies of KxFeyTi8-yO16 (x = 1.4–1.8 and y = 1.4–1.6) Ceramics with Hollandite Structure

Some solid solutions with the chemical composition KxFeyTi8-yO16 (KFTO) and a hollandite-like structure were successfully synthesized by modified sol–gel method. The obtained powders were characterized using X-ray diffraction (XRD) and scanning electron microscopy (SEM). The ceramic pellets based on KFTO powders were obtained by compressing and sintering at 1080 °C for 4 h. The sinters were characterized by X-ray and impedance spectroscopy. XRD results show that KFTO powders have a mono-phase tetragonal structure at x = 1.4–1.8 and y = 1.4–1.6. However, it was recognized that the hollandite-like phase could be broken during sintering to form TiO2 and Fe2TiO5 crystals distributed throughout the volume of the ceramics. A frequency dependency of dielectric properties for the sinters was studied by impedance spectroscopy. It was found that an increase in the TiO2 (rutile) phase during the sintering contributes to a decrease in dielectric losses. At the same time, the KFTO ceramics with reduced content of potassium had increased permittivity. The contribution of electron-pinned defect dipoles (EPDD) and internal barrier layer capacitance (IBLC) in the permittivity of the obtained ceramics was estimated using the Havriliak–Negami equation. It is shown that the KFTO ceramics have the polydisperse characteristic of dielectric relaxation. The observed grain and grain boundary dipole relaxation times were 1.03 × 10−6 to 5.51 × 10−6 s and 0.197 to 0.687 s, respectively.

High breakdown electric field in (Ta1−xPrx)0.03Ti0.97O2 colossal permittivity ceramics through defect chemistry optimization

In this work, a novel (Ta1−xPrx)0.03Ti0.97O2 (x = 0.3, 0.5, 0.7 and 0.9) ceramic was fabricated via a solid-state reaction (SSR) method using an efficient defect engineering strategy, and the microstructure, breakdown electric field and charge transport processes were investigated in detail. All co-doped ceramics exhibit a pure rutile structure and the grain size is effectively refined by Pr/Ta ion doping. Notably, the ceramic sample with x = 0.9 displays a low tanδ of 0.018 and a large ε' of 1.74 × 104, enhancing temperature stability from RT to 200 ◦C (Δε′(T)/ε′30 = 1.5%, at 1 kHz) and Eb of 2.07 kV/cm. XPS and complex impedance spectroscopy analyses show that the excellent electrical properties of (Ta1−xPrx)0.03Ti0.97O2 ceramics originate from grains with electron-pinned defect dipoles (EPDD) and insulating grain boundaries. The (Ta1−xPrx)0.03Ti0.97O2 ceramics possess enhanced breakdown field strength and excellent giant dielectric properties, making them potential candidates for capacitors.

Dielectric Responses of (Zn0.33Nb0.67)xTi1−xO2 Ceramics Prepared by Chemical Combustion Process: DFT and Experimental Approaches

The (Zn, Nb)-codoped TiO2 (called ZNTO) nanopowder was successfully synthesized by a simple combustion process and then the ceramic from it was sintered with a highly dense microstructure. The doped atoms were consistently distributed, and the existence of oxygen vacancies was verified by a Raman spectrum. It was found that the ZNTO ceramic was a result of thermally activated giant dielectric relaxation, and the outer surface layer had a slight effect on the dielectric properties. The theoretical calculation by using the density functional theory (DFT) revealed that the Zn atoms are energy preferable to place close to the oxygen vacancy (Vo) position to create a triangle shape (called the ZnVoTi defect). This defect cluster was also opposite to the diamond shape (called the 2Nb2Ti defect). However, these two types of defects were not correlated together. Therefore, it theoretically confirms that the electron-pinned defect-dipoles (EPDD) cannot be created in the ZNTO structure. Instead, the giant dielectric property of the (Zn0.33Nb0.67)xTi1−xO2 ceramics could be caused by the interfacial polarization combined with electron hopping between the Zn2+/Zn3+ and Ti3+/Ti4+ ions, rather than due to the EPDD effect. Additionally, it was also proved that the surface barrier-layer capacitor (SBLC) had a slight influence on the giant dielectric properties of the ZNTO ceramics. The annealing process can cause improved dielectric properties, which are properties with a huge advantage to practical applications and devices.

Controllable low-temperature flash sintering and giant dielectric performance of (Zn, Ta) co-doped TiO2 ceramics

In this study, the challenge of high-temperature and long-time sintering of (Zn, Ta) co-doped TiO 2 ceramics is solved successfully using flash sintering technology. Joule heating and a high heating rate make the sample compact rapidly at low temperatures (1050 °C in 24 min). When the electric field was equal to 200 V/cm, high permittivity (ε' ∼ 1.32 × 10 4 ), low dielectric loss tangent (tan δ ∼ 0.27), and nonlinear coefficient ( α ∼ 5.8) values were obtained. Flash sintered samples have more free electrons, resulting in a high dielectric constant. Further, the higher the electric field, the smaller the grain resistance of the sample; this condition is conducive to reducing dielectric loss. giant dielectric performance is explained by the combined action of the electron-pinned defect dipole theory and the internal barrier layer capacitance effect. Therefore, this study provides a promising prospect for the green preparation of co-doped TiO 2 giant dielectric ceramics.

Colossal permittivity of (Tm+Nb) co-doped rutile-TiO2 ceramics with ultralow dielectric loss and excellent thermal stability

(Tm0.5Nb0.5)xTi1−xO2 (x = 0, 0.01, 0.02, 0.04 and 0.06) (TNTO) ceramics were prepared by solid-state reaction method. The effect of (Tm+Nb) co-doping concentration on the phase, microstructure and dielectric properties of the fabricated ceramics were investigated. A ultralow dielectric loss (0.006, at 1 kHz) and colossal permittivity (CP) (2.17 ×104, at 1 kHz) were obtained in the prepared TNTO ceramics (x = 0.01). The dielectric properties of the (Tm0.5Nb0.5)0.01Ti0.99O2 ceramics show excellent temperature- and frequency-stability in the range of − 150–260 °C (Δε′ (T)/ε′30< ± 15%, at 1 kHz) and 20–106 Hz. It was found that, the dielectric properties of (Tm+Nb) co-doped TiO2 ceramics have three significant temperature-dependent relaxations caused by electron-pinned defect-dipoles (EPDD) effect, internal barrier layer capacitance (IBLC) effect and electrode effect, respectively. The reported (Tm+Nb) co-doped TiO2 ceramics with ultralow dielectric loss and excellent thermal stability could be considered as one of the most promising candidates for applications in microelectronics.

Acceptor-donor concentration dependent polaronic relaxation, pinned electron defect dipole characteristic and colossal permittivity in co-doped rutile (Zn1/3Nb2/3)xTi(1-x)O2 (x = 0.02, 0.04, 0.06 and 0,08) ceramics

Colossal permittivity with low loss tangent has been achieved by co-substitution of Zn and Nb in TiO2. Incorporation of the divalent and pentavalent ions has been confirmed by structural and Raman spectroscopic analysis. Specific ratio of acceptor-donor pairs led to observation of colossal permittivity (∼104) with a low loss tangent (<0.1). Evidence of localized donor electrons in the dielectric response shows the generation of electron pinned defect dipoles. Low-temperature dielectric relaxation has been observed which correspond to the polaronic conduction following Arrhenius law. As the acceptor-donor content increases, the polaronic relaxation dynamics occurs at higher temperatures. This also reveals that the defect complexes are strongly correlated. Permittivity values corresponding to the loss tangent minima have been compared as a function of acceptor-donor content. Finally, optimum sintering temperature, frequency, measurement temperature, and composition have been identified.

Third-order optical nonlinearity of indium-doped rutile TiO2 thin films

Rutile TiO2 and Ti0.9In0.1O2 thin films were fabricated using a pulsed laser deposition method. We employed the optical transmission spectra to reveal the good transparency of the films in the visible spectral range of 330 to 900 nm. The absorption edge of the Ti0.9In0.1O2 film is blue-shifted compared with that of undoped TiO2 film. The third-order optical nonlinearity of the films was investigated by using a z-scan method with a pulse laser operating at 532 nm with a duration of 55 ps. The results show that the Ti0.9In0.1O2 and TiO2 films exhibit nonlinear saturable absorption and negative nonlinear refraction. The doping of In ions does not change the nonlinear optical absorption of the TiO2 film significantly. However, the nonlinear refractive index of Ti0.9In0.1O2 film is about two times larger than that of undoped TiO2 film. The local electron-pinned defect-dipoles and widening bandgap in the Ti0.9In0.1O2 film can be used to explain the observed results.

Defect engineering in rare‐earth‐doped BaTiO3 ceramics: Route to high‐temperature stability of colossal permittivity

AbstractHigh‐performance colossal‐permittivity (CP) materials have huge potential applications in the miniaturization of electronic components and high‐energy storage applications. Here, we report CP behavior in rare‐earth Ln‐doped BaTiO3 (Ln = La, Ce, Pr, Nd, Sm, Gd, Dy, Ho, and Er) ceramics. CP (&gt;1 × 105) and low loss (&lt;5% at 1 kHz) were achieved. Additionally, all ceramic samples with excellent temperature stability over a wide temperature range (25–250°C). X‐ray photoelectron spectroscopy verified the existence of point defects (Ti3+ and ) in Ln‐doped BaTiO3 ceramic samples annealed in an N2 atmosphere. Electron paramagnetic resonance further demonstrated the existence of Ti3+. The coupling of point defects forms an electron‐pinned defect‐dipoles (EPDD) effect and induces strong hopping polarization. In addition, an internal barrier layer capacitance (IBLC) effect and a surface barrier layer capacitor (SBLC) effect are identified by impedance spectroscopy and DC bias voltage. The CP is attributed to the combined effect of EPDD, IBLC, and SBLC. Furthermore, the high‐temperature stability of CP is related to the strong coupling of defect‐dipole complexes.

Origin of colossal dielectric performance of rutile-TiO2 by substitution with Y3++Ta5+ dopants: DFT calculations and experimental study

Highly compacted microstructures of Y3++Ta5+ co-doped TiO2 (YTTO) ceramics were fabricated. The YTTO ceramics contain not only the rutile structure but also contains the secondary phase of the microwave dielectric YTaTiO6 particles. The decrease in the mean grain size of the YTTO was attributed to the inhibited grain growth due to the pinning effect of the YTaTiO6 phase particles. The YTTO can exhibit a colossal permittivity (εˊ ∼ 8.5 × 104) and low dielectric loss (tanδ ∼ 0.021). Moreover, the excellent temperature stability of εˊ was found to be less ±15% over a wide temperature range. The semiconducting and highly insulating parts in the YTTO ceramics were proved using impedance spectroscopy. The reduction of Ti4+ to Ti3+ was partially existed due to the substitution of donor Ta5+, leading to the semiconducting grains. The DFT calculation showed that the defect structure of Y23+V0··Ti3+ was not preferable to create. Therefore, the electron-pinned defect-dipoles were theoretically predicted to be not formed. Instead, the interfacial polarization at the interface between semiconducting grain and insulating grain boundary/microwave YTaTiO6 phase plays a primary role in the overall dielectric properties.

Giant dielectric response and relaxation behavior in (Tm + Ta) co-doped TiO2 ceramics.

Dielectric materials with huge dielectric constants are attracting attention due to the growing demand for microelectronics and high energy-storage devices. In this work, Tm + Ta co-doped TiO2 ceramics were prepared by a solid-state reaction (SSR) method, and the microstructure and dielectric behavior were investigated. A ultrahigh permittivity (εr ∼ 2.26 × 104) and very low loss (tan δ ∼ 0.011) are achieved at 1 kHz for (Tm0.5Ta0.5)0.01Ti0.99O2 ceramics. XPS analysis confirms that the high dielectric constant and low dielectric loss are attributed to the electron pinned defect dipole (EPDD) response formed by the coupling of Ti3+ and oxygen vacancies. In addition, impedance analysis and frequency dependent dielectric constant under a DC bias indicate that the presence of the internal barrier layer capacitance (IBLC) response and electrode response at low to medium frequencies (<106 Hz) also contribute significantly to the dielectric constant. The findings reported in this work provide valuable insights into the simultaneous realization of a low dielectric loss and high permittivity in Tm + Ta co-doped TiO2 ceramics and other related dielectric ceramics.

Intrinsic Enhancement of Permittivity with Ultralow Dielectric Loss in Donor-Acceptor Co-Doped Rutile TiO2 Ceramics

The immense potential of colossal dielectric materials for use in high-energy-density storage applications has driven much recent development and research. The discovering of such dielectric materials with the required high permittivity and low dielectric loss is still a highly challenging. Herein, the donor-acceptor co-doped TiO2 has been developed based on (Mg0.5W0.5) x Ti1- x O2, (In0.5W0.5) x Ti1- x O2 and (Ni0.5Nb0.5) x Ti1- x O2; where x = 0.005–0.01, that manifests high permittivity (>104). The resulted permittivity attains the quadruple than that of pure TiO2 ceramic with low dielectric loss of ∼0.02 over a broad temperature range. This performance is corresponded to the electron-pinned defect-dipoles, providing the extra dielectric response to those of rutile TiO2 host ceramics. This research offers the way to develop functional colossal-dielectric materials by engineering complex defects into the bulk that will help for further discovery of promising new dielectric materials in future.

High dielectric performance and multifarious polarizations in (Lu + Ta) co-doped TiO2 ceramics

ABSTRACT Materials with high dielectric constant have broad application prospects in energy storage elements. In this work, (Lu0.5Ta0.5)xTi1-xO2 ceramics (x = 0, 0.01, 0.02 and 0.04) were synthesized by a standard conventional solid-state reaction. Remarkably, (Lu0.5Ta0.5)0.01Ti0.99O2 ceramic exhibits a high dielectric permittivity (2.55 × 104), low dielectric loss (0.012) and excellent stabilities of frequency and temperature (−150–150°C and 20–5 × 106 Hz). The formation mechanism of excellent dielectric properties was studied based on analysis of the XRD, SEM, XPS, complex impedance and electric modulus. Colossal permittivity (CP) and low tan δ were attributed to the internal barrier layer capacitance (IBLC) effect, electron-pinned defect-dipole (EPDD) effect and electrode effect. This work has important guidance for the further research of giant dielectric materials.