Impure Materials Research Articles

Electrochemical Impact of Inhomogeneous Binder Distribution in Lithium-Ion Battery Electrodes

In recent years, the application possibilities of the lithium-ion battery (LIB) have increased significantly. Moreover, the demand for LIBs will rise in the next few years, especially in the automotive sector. This leads to an increasing importance of careful management of the limited lithium resources. Battery production offers high savings potential, as the current scrap rate is around 5-30% [1,2]. The scrap arises in the various process steps such as electrode production, battery conditioning or even from impure raw materials. Especially during the electrode production including mixing, coating, drying and calendaring, various defects can be implemented into the electrodes. Defects such as compositional inhomogeneities (e.g., inhomogeneous binder distribution), microstructural inhomogeneities (e.g., thickness variations), line defects, point defects or even foreign particle contamination can lead to increased scrap rates [3].For the detection of defects, there are already a few established methods such as computed thermography, camera-based optical systems, or post-mortem analyses. However, the detection of the defects might not be sufficient to evaluate the electrode usability since the influence might still be tolerable. Therefore, the impact of the defect type, size, and concentration and resulting determination of the tolerance limits is decisive for the reduction of production waste.In this work we focus on the influence of compositional inhomogeneities on the battery performance. Compositional inhomogeneities like inhomogeneous binder distribution can modify the local electrode characteristics e. g. porosity/tortuosity. This can lead to local higher or lower c-rate followed by faster or slower local degradation. In worst case these inhomogeneities can cause lithium plating or short circuits and shorten the lifetime of LIBs significantly.To determine the criticality and establish tolerance limits, we produced and analyzed defective and defect-free electrodes. For the determination of the impact of the inhomogeneities we developed a special experimental setup that allows us the analysis of the internal dynamics of the interaction between defect-containing (selective modification of the binder content) and defect-free (target binder content) electrodes. Therein, compensating currents continuously redistribute the inhomogeneous charges in electrodes with different binder content. This balancing effect was studied in terms of the caused accelerated aging.This experimental approach provides a foundation for further investigation and for deep understanding of the effect of electrode defects. This knowledge represents a basis for further developing of effective quality assurance strategies and reducing scrap rates accompanying by careful management of the limited lithium resources.[1] Gaines, L.; Dai, Q.; Vaughey, J. T.; Gillard, S.: Direct Recycling R&D at the ReCell Center. Recycling. 2021, 6 (2), 31. DOI: 10.3390/recycling6020031. [2] Brückner, L.; Frank, J.; Elwert, T.: Industrial Recycling of Lithium-Ion Batteries—A Critical Review of Metallurgical Process Routes. Metals 2020, 10 (8), 1107. DOI: 10.3390/met10081107. [3] du Baret de Limé, A.; Lein, T., Maletti, S.; Schmal, K.; Reuber, S.; Heubner, C. and Michaelis, A.: Impact of Electrode Defects on Battery Cell Performance: A Mini Review. Batteries & Supercaps 2022, 5, e202200239, doi.org/10.1002/batt.202200239.

Distribution of Heterogeneous, Highly Impure Soy Material in a Deep Air Channel

The paper highlights a lack of machines and equipment capable of cleaning highly impure soybean material efficiently and productively. Most of the existing grain cleaning machines are designed for the materials conforming to GOST 17109-88 that specifies weed and oilseed impurity contents of 2 and 6 percent, respectively. In reality, a typical soybean post-harvest waste often contains 20 to 60 percent of material unsuitable for extracting raw protein, that makes this type of material completely non–separable for this type of machine. (Research purpose) The research aims to determine the optimal efficiency of separating heterogeneous bulk mixtures in a vertically ascending air channel. (Materials and methods) To accomplish this, the authors employed a rotary batch classifier RBK 30 and a prototype sample of a precision air classifier PAC with column air flow accelerators. The paper defines impurity separation completeness and soybean waste separation efficiency in a novel pneumatic classifier, considering the accelerator thickness and the height above the processed material. (Results and discussion) The findings reveal that traditional pneumatic channels achieve no more than 20 percent of separation efficiency for highly impure soybean material, while the precision air classifier demonstrates approximately a 45 percent separation. (Conclusions) Typical air flow machines struggle with high impurity of material. The separation efficiency of highly impure material can be enhanced by equalizing the air flow velocity inside and above the layer of the separated material and installing a core air flow accelerator. The study indicates that the material being processed can be separated by air flow, provided a specialized pneumatic separation channel is used. Due to the ratio of the core accelerator height and the height above the material, the air flow velocity inside and above the separated layer is equalized.

Photoluminescence of CdTe and CdZnTe compounds doped with 2% selenium

The addition of 2 % of selenium in CdTe and CdZnTe (CZT) exhibited an additional acceptor-bound exciton in photoluminescence (PL). From the PL and inductively coupled plasma mass spectrometer (ICP/MS) analyses, the additional acceptor-bound exciton emission is associated with a Cu impurity in the relatively low-purity (5N) precursor CdSe starting material. In addition, thermal quenching of the acceptor/donor bound exciton emissions do not require a shift to any higher excited states or to the free exciton state. ICP/MS analysis also showed a higher concentration of Sn in CdZnTeSe (CZTS) compared to CdTe and CZT which is known to form a deep level trap at around EC – 0.83 eV. The trapping and de-trapping times indicate that the Sn-related deep trap acts as an electron trapping center. The relatively low electron mobility-lifetime product of CZTS might be correlated with the concentration of Sn in the impure CdSe material. Pulse height spectra using an Eu-152 gamma-ray source was taken for a 2-mm-thick planar CZTS detector. The spectra clearly showed all the expected gamma peaks with energy lower than 344.3 keV.

Is One of the Least Coordinating Anions Suitable to Serve as Electrolyte Salt for Magnesium‐Ion Batteries?

AbstractWeakly coordinating anions (WCAs) are considered promising candidates for application as electrolytes in multivalent post‐lithium batteries. One strong candidate as electrolyte salt for Mg battery application is [Mg(L)x][Al(ORF)4]2 (L=MeCN (acetonitrile), DME (1,2‐dimethoxyethane); x=3, 6; RF=C(CF3)3) that contains [Al(ORF)4]− as one of the least coordinating WCAs known. Here we present a novel synthetic route, for which vibrational, NMR and XRD analyses show the formation of a clean, pristine electrolyte salt without the common contaminants found in published synthetic routes. The electrochemistry of this pristine and pure [Mg(DME)3][Al(ORF)4]2 electrolyte (0.2 m in DME) was investigated via cyclic voltammetry (CV). In contrast to previous publications using impure materials, the CV showed no sign for Mg deposition from the pristine electrolyte for all conditions tested. This also holds when including the additives LiCl, NaCl, MgCl2, Li[BH4] or a mixture of MgCl2/Mg[HMDS]2 (HMDS=hexamethyldisilazide) in THF. Quantum chemical calculations suggested the possibility of anion decomposition at the negative electrode, leading to an electronically insulating MgF2 layer (rutile structure) on all the electrode materials tested. This hypothesis was confirmed by an XPS investigation of electrodes exposed to the electrolytes containing the WCAs [Al(ORF)4]− and [Al(OC(H)(CF3)2)4]− at negative potentials, which only showed the presence of MgF2 for the [Al(ORF)4]− electrolyte, but not for the related [Al(OC(H)(CF3)2)4]− electrolyte (which allowed to deposit magnesium reversibly on the electrode).

Prospects of conducting polymer as an adsorbent for used lubricant oil reclamation

Lubricant oil is used for reducing friction, dust, corrosion and protection against wear between metallic parts which are in contact with each other in different types of machines and engines. Used lubricant oils (ULOs) are highly polluted materials and it is harmful to nature. These pollutants contains toxic materials such as Poly-aromatic hydrocarbons (PAHs), Polychlorinated biphenyls (PCBs), and soot, air dust and heavy metals, makes black oil as a serious hazard. If not properly handled or disposed of, this can lead to significant health and environmental problems. Hence, the controlling of waste oil needs a sustainable solution for effective management and protection of the environment. Treatment of used lubricant oil is one of the simplest routes to discard polluted materials from waste oil. Over the decades, researchers have investigated several reported methods for refining used lubricant oil. Meanwhile, Adsorption is an effective pre-treatment strategy for preliminary purification of used lubricant oil. Conducting polymers (CPs) have attracted a lot of attention due to its unique electronic and optical properties. In this review, various types of conducting polymer based adsorbents are discussed to remove impure toxic materials from any type of aqueous solution. Thus, the main purpose of this review is to explore how conducting polymer and its composites can use for refining used lubricant oil. Waste lubricating oil can be pretreated in advance by filtering it via a column packed with conducting polymer-based clay composites.

Use of dilatometer to screen refractory raw materials

AbstractSudden shortage of a particular raw material due to freight disruptions, competitive market, and COVID restrictions have frequently forced the refractory industry to rapidly develop alternative formulations using available low‐cost materials. These alternative ingredients might cursorily appear to have similar total impurity content, but the presence of certain impurity combinations depending on the refractory type can produce more fluid liquid phase at high temperature, thereby drastically reducing hot strength. Undetected by the commonly used X‐ray fluorescence (XRF) analysis, the low‐cost material might differ in mineral‐phase content, whose phase transformations during firing might create excessive expansion producing warpage of the refractory along with a high porosity reducing strength and corrosion resistance. Finally, those cheap raw materials might have similar sieve analysis to that of the standard ingredient but might have much lower tapped density, which would introduce detrimental porosity into the resulting refractory. Hence, time‐consuming trials are often performed. Dilatometer studies on pressed or cast samples in a single test can identify reaction temperatures of spinel or mullite formation, which expand during firing, along with the amount of expansion and exact times at which firing needs to be done. It can also compare relative shrinkage due to liquid‐phase formation among impure raw materials like recycled grogs or low‐grade ores. Finally, dilatometric step scan is shown as a fast technique to prepare in‐house, low‐cost reactive spinel powder, which can also work for mullite.

Structural Insights into the Vapochromic Behavior of Pt- and Pd-Based Compounds

Anionic complexes having vapochromic behavior are investigated: [K(H2O)][M(ppy)(CN)2], [K(H2O)][M(bzq)(CN)2], and [Li(H2O)n][Pt(bzq)(CN)2], where ppy = 2-phenylpyridinate, bzq = 7,8-benzoquinolate, and M = Pt(II) or Pd(II). These hydrated potassium/lithium salts exhibit a change in color upon being heated to 380 K, and they transform back into the original color upon absorption of water molecules from the environment. The challenging characterization of their structure in the vapochromic transition has been carried out by combining several experimental techniques, despite the availability of partially ordered and/or impure crystalline material. Room-temperature single-crystal and powder X-ray diffraction investigation revealed that [K(H2O)][Pt(ppy)(CN)2] crystallizes in the Pbca space group and is isostructural to [K(H2O)][Pd(ppy)(CN)2]. Variable-temperature powder X-ray diffraction allowed the color transition to be related to changes in the diffraction pattern and the decrease in sample crystallinity. Water loss, monitored by thermogravimetric analysis, occurs in two stages, well separated for potassium Pt compounds and strongly overlapped for potassium Pd compounds. The local structure of potassium compounds was monitored by in situ pair distribution function (PDF) measurements, which highlighted changes in the intermolecular distances due to a rearrangement of the crystal packing upon vapochromic transition. A reaction coordinate describing the structural changes was extracted for each compound by multivariate analysis applied to PDF data. It contributed to the study of the kinetics of the structural changes related to the vapochromic transition, revealing its dependence on the transition metal ion. Instead, the ligand influences the critical temperature, higher for ppy than for bzq, and the inclination of the molecular planes with respect to the unit cell planes, higher for bzq than for ppy. The first stage of water loss triggers a unit cell contraction, determined by the increase in the b axis length and the decrease in the a (for ppy) or c (for bzq) axis lengths. Consequent interplane distance variations and in-plane roto-translations weaken the π-stacking of the room-temperature structure and modify the distances and angles of Pt(II)/Pd(II) chains. The curve describing the intermolecular Pt(II)/Pd(II) distances as a function of temperature, validated by X-ray absorption spectroscopy, was found to reproduce the coordinate reaction determined by the model-free analysis.

Identification of ginseng radix in Chinese medicine preparations by nested PCR-DNA sequencing method and nested PCR-restriction fragment length polymorphism

Ginseng Radix, the dried root of Panax ginseng, is easily confused with other herbs of the Panax species by appearance. In Chinese medicine preparations, it is difficult to identify misuse of Ginseng Radix. In this study, the nested PCR and DNA sequencing methods were established for the identification of Ginseng Radix, whereas the combination of nested PCR and restriction fragment length polymorphism (RFLP) could differentiate Ginseng Radix from other Panax species and thus certify the use of impure raw material of Ginseng Radix in Chinese medicine preparations. Nested PCR and DNA sequencing methods were applied to verify ginseng ingredients in the preparations. Of the 58 samples analyzed, 48 samples contained P. ginseng, 8 P. quinguefolius, and 2 P. notoginseng. Utilizing restriction enzyme BstYI and DdeI, nested PCR products of the samples were digested for restriction fragment lengths of polymorphism (RFLP). It was proven that 23 of the 58 samples contained a mixture of Ginseng Radix and Panacis quinquefolii Radix. Twenty-five samples contained pure raw material of Ginseng Radix. Ginseng components of 10 samples were confirmed using a substitute of P. quinguefolius or P. notoginseng. The RFLP results were consistent with those of the sequencing method results.

Physical models to evaluate the performance of impure phase change material dispersed in building materials

Abstract Currently, the introduction of phase change materials (PCM) in building materials is recognized as a popular technique for reducing interior temperature fluctuations and improving the energy efficiency of buildings. Conventionally, PCM in construction materials is different with bulk PCM as it incorporates impurities and acts as a binary mixture. For this reason, physical models to describe heat transfers inside such materials are highly requested. This paper presents four physical approaches that can be applied to examine heat transfer in impure PCM dispersed inside a building material. These models have been successfully verified and tested using experimental results from the literature. A significant hysteresis is observed during the phase transition as a result of thermal gradients within the composite material as well as the non-symmetric enthalpy profile as a function of temperature.

A generalized self-consistent approach to study position-dependent mass in semiconductors organic heterostructures and crystalline impure materials

Abstract The purpose of this study is to generalize the Coordinate Integral Transform recently introduced in literature for the self-consistent solution of Schrodinger equation in one-dimensional systems with position-dependent mass. It was revealed that the present generalized approach reveals several motivating properties in material sciences and may be used to model and solve a large number of problems arising in solid state sciences ranging from semiconductors heterostructures to organic semiconductors and crystalline solids subject to impurities.

Eutectic Synthesis of the P2-Type NaxFe1/2Mn1/2O2 Cathode with Improved Cell Design for Sodium-Ion Batteries

An engaging area of research in sodium-ion batteries (SIBs) has been focusing on discovery, design and synthesis of high-capacity cathode materials in order to boost energy density to levels close enough to the state-of-the-art lithium-ion batteries. Of particular interest, P2-type layered oxide, Na2/3Fe1/2Mn1/2O2, has been researched as a potential cathode in SIBs based on its high theoretical capacity of 260 mAh/g and use of non-critical materials. However, the reported synthesis methods are not only complex and energy-demanding, but also often yield inhomogeneous and impure materials with capacities less than 200 mAh/g under impractical test conditions. Here, we report a novel synthesis route using low temperature eutectic reaction to produce highly homogeneous and crystalline, and impurity-free P2-NaxFe1/2Mn1/2O2 with enhanced Na-ion diffusivity and kinetics. The overall electrochemical performances of the Na-ion cells have been improved by pairing the P2-cathode with pre-sodiated hard carbon anodes, leading to reversible capacities in the range of 180 mAh/g. This new approach is a contribution towards the simplification of synthesis and scalability of sodium-based cathodes with high crystallinity and fine-tuned morphology, and the realization of a sodium-ion battery system with lower cost and improved electrochemical performance.

Oxidation of SiCf-SiC CMC cladding tubes for GFR application in impure helium atmosphere and materials interactions with tantalum liner at high temperatures up to 1600°C

The oxidation kinetics of SiCf-SiC cladding tube segments and sandwich tubes with an inner tantalum layer in impure helium atmosphere prototypical for GFRs was investigated at ambient pressure in the temperature range between 900 °C and 1600 °C using a thermogravimetric device. The transition from passive oxidation (formation of a protective silica scale) to active oxidation (volatilization of silica due to the formation of SiO and other volatile species) occurred between 1200 °C and 1300 °C. Hence, during target operational temperatures of 900–1000 °C, the CMC cladding material should withstand long-term operation with respect to oxidation and corrosion. At higher temperatures beyond 1300 °C, i.e. under accident conditions, volatilization of composite constituents would lead to serious degradation of the SiC-based cladding tubes. Severe interactions between the tantalum layer and silicon carbide with the formation of Ta silicides and carbides were found to become significant at temperatures higher than 1300 °C.

Dynamic Heat Transfer Study of a Triangular-Shaped Latent Heat Storage Unit for the Attic Space of a Domestic Dwelling

Abstract A two-dimensional (2D) numerical study is carried out to investigate the thermal performance of an impure phase-change material (PCM) in an equilateral triangular-shaped double pipe heat exchanger. To tackle the irregular boundaries, a nonorthogonal body-fitted coordinate (BFC) transformation technique is employed. The nondimensional transformed curvilinear conservation equations for mass, momentum, and energy are written in terms of physical variables and they are solved using a control-volume based finite difference method on a staggered grid arrangement. The developed model is then used to study the effects of the inner tube wall temperature, the initial temperature of the solid PCM, and the shape, as well as the position of the inner tube in the annulus on the melting characteristics, and cumulatively stored energy. Various quantities such as average Nusselt numbers over the inner tube surface, the total and complete melt fractions, and the latent and total stored energies all as a function of the melting time are reported. A correlation for the average Nusselt number on the inner tube wall is also provided. The numerical results show that the shape and the placement of the inner tube are crucial for the efficient design of a latent heat thermal energy storage (LHTES) system. The storage of energy is greatly influenced by the change of the inner tube wall temperature compared to the change of initial solid PCM temperature.

Energy Storage by Melting Commercial Change Phase Materials in Hexagonal-Shaped Heat Exchangers

A two-dimensional melting of a technical-grade phase-change material is modeled. The phase-change material is placed in the annular space formed by an outer regular hexagonal tube and an inner tube. A nonorthogonal boundary fitted coordinate method is implemented on a staggered grid arrangement. The mushy region of the impure phase-change material has been accommodated through the enthalpy-porosity scheme. A set of parametric studies is carried out. Selected results are presented as a function of time for the velocity and temperature fields, the cumulatively stored energy, the total melt fraction, and the average Nusselt number on the inner tube. The oblate-shaped inner tube results in the highest melting rate and stores the maximum energy among the studied units irrespective of the shape and vertical position of the inner tube. Among the three vertical positions of the inner circular tube, when the center of the inner tube is placed at one-third height from the base of the outer tube, it shows the greatest thermal efficiency, and the worst performance is obtained for the upper position of the inner tube at the two-thirds height of the outer tube. With the increase in the Rayleigh number (wall temperature), the amount of energy storage is enhanced.

Transient melting of an impure paraffin wax in a double-pipe heat exchanger: Effect of forced convective flow of the heat transfer fluid

A transient 2-D numerical study is carried out on the melting (energy storage) of an impure phase change material (paraffin wax) embedded in the annular gap formed by an outer equilateral pipe and an inner tube carrying the heat transfer fluid. A non-orthogonal curvilinear coordinate method is used to account correctly for the irregular boundaries of the annular domain. A set of parametric studies is performed by varying the bulk temperature and mass flow rate of the heat transfer fluid (HTF). Besides, numerical simulations are also made to ascertain the effects of the various cross-sectional shapes and positions of the inner tube as well as the initial state of the solid PCM on the melting process. The temporal velocity and temperature profiles are shown in addition to the cumulatively stored energy and total melt fraction as a function of the melting time. The results indicate that the bulk temperature of the HTF imposes a significant effect on the melting process compared to its mass flow rate. The lower eccentric position of the inner circular tube provides the maximum energy storage capacity compared to its concentric position. The concentrically placed circular inner tube provides the maximum energy storage in the annulus relative to the other two cross-sectional inner tubes namely prolate- and oblate-shaped elliptical tubes.

Mid-infrared optical properties of pyrolytic boron nitride in the 390–1050 °C temperature range using spectral emissivity measurements

This paper shows a systematic experimental and theoretical study on the temperature dependence of the infrared optical properties of pyrolytic boron nitride (pBN), from 390 to 1050°C for wavelengths between 4 and 16μm. The temperature dependence of these properties has never been analyzed before. The measured emissivity spectra were fitted to a dielectric function model and an effective medium approximation. The phonon frequencies and dielectric constants agreed well with room temperature experimental values from the literature, as well as with ab initio and first principles calculations. In addition, the phonon frequencies of the perpendicular mode and the dielectric constants of the parallel mode showed an appreciable parabolic temperature dependence, which justifies the interest of more theoretical efforts in order to explain this behavior. Finally, the results of this work demonstrate that thermal emission spectroscopy allows obtaining the values of the optical and dielectric parameters of impure ceramic materials in a simple manner as a function of temperature.

Modeling of the melting characteristics of commercial paraffin wax in an inverted equilateral triangular enclosure: Effect of convective heat transfer boundary conditions

ABSTRACTA horizontal double-pipe heat exchanger with an inverted outer equilateral triangular tube is modeled to numerically investigate the low-temperature thermal energy storage capability of an impure phase change material (PCM). The energy source fluid (hot water) flows through the inner tube and transfers heat to the PCM (heat sink) residing in the annular gap. The results show that the inlet temperature of the heat transfer fluid (HTF) has a significant effect on the melting process compared with the mass flow rate (MFR). The configuration, as well the concentricity/eccentricity of the inner tube has a great influence on the energy storage.

2-D numerical investigation of melting of an impure PCM in the arbitrary-shaped annuli

A transient numerical study is carried out using a boundary-fitted coordinate (BFC) technique to model the melting characteristics of an impure phase-change material (PCM) in the annular gap formed by an inverse outer equilateral triangular-shaped enclosure and various shaped inner tubes. A control-volume based finite difference method is used to solve the non-dimensional transformed curvilinear conservation equations for mass, momentum, and energy in terms of the physical variables. An enthalpy-porosity scheme is used to model the mushy region melting problem. The developed code is verified with the available experimental data. The effects on the melting characteristics of the PCM of the inner tube wall temperature (Rayleigh number), the initial condition of the PCM, the cross-sectional shape as well as the vertical position of the inner tube inside the annulus are ascertained. The velocity and temperature fields, the total and complete melt fractions, and the latent and total stored energies as a function of the melting time are reported. From the predicted results it is found that the heat exchanger with a vertically placed eccentric inner circular tube provides the maximum energy storage capacity. The wall temperature of the inner tube, as well as the initial temperature of the solid PCM, both has a significant influence on the melting rate of the impure PCM.

Improved electrochemical performance of Li4Ti5O12 by reducing rutile TiO2 phase impurity and particle size

Pure lithium titanate (Li4Ti5O12) powder having particle size of 100 (±38) nm has been prepared by solid-state synthesis method, using planetary ball milling at lower speed of 900 rpm as compared to high energy ball milling (3000 rpm) and characterized by X-ray diffractometer, field emission scanning electron microscopy and thermogravimetric analysis. Electrochemical performance of Li-ion battery cells is determined by charging–discharging and cyclic voltammetry tests. The material has shown very high discharge capacity of 171 and 108 mAhg−1 measured at current rates of 0.1C and 5C, respectively, as compared to 160 and 71 mAhg−1 for impure Li4Ti5O12 material (containing rutile phase of TiO2) having particle size 213 (±45) nm. Capacity retention of pure Li4Ti5O12 was 91% after 100 cycles, whereas the impure Li4Ti5O12 has shown the retention ability of 85%.

Robust insulating La and Ti co-doped BiFeO3 multiferroic ceramics

Low resistivity and high dielectric loss are two major problems associated with the fabrications of BiFeO3 multiferroic ceramics. Adapting co-doping on the A- and B-sites, robust insulating Bi0.98La0.02Fe0.99Ti0.01O3 ceramics with resistivity ~1011 Ω m measured applying electric field 90 kV/cm and dielectric loss tanδ below 0.02 over frequency range of 100 Hz–2 MHz were prepared using a refined solid state reaction electroceramic processing. Intentional La/Ti co-substitution was experimentally illustrated to form ternary solid solution, which enhances thermodynamic stability of BiFeO3 perovskite phase, allowing obtain high resistive low dielectric loss bismuth ferrite ceramics. Meanwhile, passive unknown impure ions from Bi2O3 and TiO2 raw oxides were also found combining synergetic effect available to obtain low dielectric loss ceramics. In contrast to the traditional method introducing vacancies via doping heterovalent ions, various kinds of vacancies were introduced in advance into the ceramic samples through controlling chemical stoichiometry via employing impure raw materials, and they are experimentally demonstrated responsible for dielectric loss relaxation behaviors and high dielectric loss observed in the Bi0.98La0.02Fe0.99Ti0.01O3 ceramics.