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Amidst the swift expansion of the electric vehicle industry, the imperative for alternative battery technologies that balance economic feasibility with sustainability has reached unprecedented importance. Herein, we utilized Perovskite-based oxide compounds barium titanate (BaTiO3) and strontium titanate (SrTiO3) nanoparticles as anode materials for lithium-ion batteries from straightforward and standard carbonate-based electrolyte with 10% fluoroethylene carbonate (FEC) additive [1M LiPF6 (1:1 EC: DEC) + 10% FEC]. SrTiO3 and BaTiO3 electrodes can deliver a high specific capacity of 80 mA h g−1 at a safe and low average working potential of ≈0.6 V vs. Li/Li+ with excellent high-rate performance with specific capacity of ~90 mA h g−1 at low current density of 20 mA g−1 and specific capacity of ~80 mA h g−1 for over 500 cycles at high current density of 100 mA g−1. Our findings pave the way for the direct utilization of perovskite-type materials as anode materials in Li-ion batteries due to their promising potential for Li+ ion storage. This investigation addresses the escalating market demands in a sustainable manner and opens avenues for the investigation of diverse perovskite oxides as advanced anodes for next-generation metal-ion batteries. [ABSTRACT FROM AUTHOR]

This paper presents the research results of multiferroic ceramic composites obtained with three sintering methods, i.e., free sintering FS (pressureless), hot pressing HP, and spark plasma sintering SPS. The multiferroic composite was obtained by combining a ferroelectric material of the PZT-type (90%) and zinc-nickel ferrite (10%). Research has shown that the combination of a magnetic material and ferroelectric materials maintains the multiferroic good ferroelectric and magnetic properties of the composites for all sintering methods. A sample sintered with the HP hot pressing method exhibits the best parameters. In the HP method, the composite sample has high permittivity, equal to 910 (at room temperature) and 7850 (at the phase transition temperature), residual polarization 2.80 µC/cm2, a coercive field of 0.95 kV/mm, and the magnetization of 5.3 and 4.95 Am2/kg at −268 °C and RT, respectively. Optimal technological process conditions are ensured by the HP method, improving the sinterability of the ceramic sinter which obtains high density and proper material compaction. In the case of the SPS method, the sintering conditions do not allow for homogeneous growth of the ferroelectric and magnetic component grains, increasing the formation of internal pores. On the other hand, in the FS method, high temperatures favor excessive grain growth and an increase in the heterogeneity of their size. In obtaining optimal performance parameters of multiferroic composites and maintaining their stability, hot pressing is the most effective of the presented sintering methods. [ABSTRACT FROM AUTHOR]

Solid electrolytes with high lithium-ion conductivity and superior stability are key components in the development of all-solid-state lithium-ion batteries. In this study, novel quaternary solid electrolytes Li 2x-y Sr 1-x-y La y TiO 3 (x = 3y/4, y = 1/7, 2/7, 3/7, 1/2, 15/28, and 4/7) were synthesized by conventional solid-state reaction approach. X-ray diffraction analysis revealed that with the increase in La3+ content, Li 2x−y Sr 1−x−y La y TiO 3 structure changes from cubic to tetragonal perovskite-type structure. Electrochemical impedance spectroscopy revealed that with the increase in y-value, enhanced conductivity was initial observed, followed by a decrease. Li 15/56 Sr 1/16 La 15/28 TiO 3 electrolyte exhibited optimal total Li-ion conductivity of 4.84 × 10−4 S cm−1, electronic conductivity of 6.84 × 10−10 S cm−1, and activation energy of 0.29 eV. On the other hand, cyclic voltammetry revealed unstable Li 1/8 Sr 1/8 La 1/2 TiO 3 , Li 15/56 Sr 1/16 La 15/28 TiO 3 , and Li 2/7 La 4/7 TiO 3 specimens at voltages of less than ~2 V, indicative of their incompatibility with lithium metal or Li 4 Ti 5 O 12 in all-solid-state batteries. Charge-discharge tests confirmed the utility of electrolytes as solid separators with good performance in semi-solid-state batteries. Overall, these results are beneficial for future research on solid electrolytes and their applications in all-solid-state lithium-ion batteries. [ABSTRACT FROM AUTHOR]

The paper presents the technology of ferroelectric-ferromagnetic ceramic composites obtained from PLZT powder (the chemical formula Pb0.98La0.02(Zr0.90Ti0.10)0.995O3) and ferrite powder (Ni0.64Zn0.36Fe2O4), as well as the results of X-ray powder-diffraction data (XRD) measurement, microstructure, dielectric, ferroelectric, and magnetic properties of the composite samples. The ferroelectric-ferromagnetic composite (P-F) was obtained by mixing and the synthesis of 90% of PLZT and 10% of ferrite powders. The XRD test of the P-F composite shows a two-phase structure derived from the PLZT component (strong peaks) and the ferrite component (weak peaks). The symmetry of PLZT was identified as a rhombohedral ferroelectric phase, while the ferrite was identified as a spinel structure. Scanning electron microscope (SEM) microstructure analysis of the P-F ceramic composites showed that fine grains of the PLZT component surrounded large ferrite grains. At room temperature P-F composites exhibit both ferroelectric and ferromagnetic properties. The P-F composite samples have lower values of the maximum dielectric permittivity at the Curie temperature and a higher dielectric loss compared to the PLZT ceramics, however, the exhibit overall good multiferroic properties. [ABSTRACT FROM AUTHOR]

Abstract: Due to increasingly global environmental and energy crises, visible light semiconductor photocatalyst with a tunable bandgap and optical properties have received attention. This study aid in the design of bifunctional MTaO3/SrTiO3(010) (M=Na, K) heterostructure photocatalyst material for environmental remediation. In this study, the stability, electronic and optical properties of coupled MTaO3 and SrTiO3 are systematically studied using the hybrid HSE06 method. The MTaO3/SrTiO3(010) heterostructure show high photocatalytic activity under visible light irradiation with good stability and reduced bandgap compared to the bulk SrTiO3. The heterostructures formed a type‐II band alignment to accelerates the interfacial charge transfer process and the photocatalytic activity. By comparing the relative ratio of effective mass, we could conclude that MTaO3/SrTiO3(010) heterostructure has not only superior mobility of charge carriers but also higher separation of photoinduced electrons and holes. The band alignment results showed that the MTaO3/SrTiO3(010) heterostructure are highly efficient for pollutants degradation and energy conversion. Significantly, the origin of the enhanced photocatalytic activity is observed from the O 2p state of SrTiO3 to the Ta 5d state of MTaO3. In summary, this study shows a key role of SrTiO3 as an electron donor to enhance the optical properties and stability of MTaO3/SrTiO3(010) heterostructure. [ABSTRACT FROM AUTHOR]

Abstract: This paper contains the results of research on chemical-looping combustion (CLC). CLC is one of the most promising combustion technologies and has the main advantage of producing a concentrated CO2 stream, which is obtained after water condensation and without any energy penalty for CO2 separation. The objective of this work was to study the chemical-looping reaction performance of novel perovskite-type oxygen carriers. The Sr(Mn1−x Ni x )O3 family was tested for its suitability as an oxygen carrier in hydrogen (syngas component) combustion for power generation. Sr(Mn1−x Ni x )O3 perovskite-type oxides with x = 0, 0.2, 0.5, 0.8, and 1.0 were prepared. Thermogravimetric measurements were performed to investigate the oxidation/reduction of the obtained materials. Reactivity tests were performed under isothermal conditions during multiple redox cycles using a thermogravimetric analyzer (TGA). For the reduction reaction, 3% H2 in Ar was used, and air was used for the oxidation cycle. The effect of reaction temperature (600–800 °C) and the number of reducing/oxidizing cycles (up to 5 cycles) on the performance of the oxygen-carrier samples developed in this study were evaluated. The stability, oxygen transport capacity, and reaction rates were analyzed on the basis of thermogravimetric TG results. The Sr(Mn1−x Ni x )O3 oxides showed stable chemical-looping performance with rapid changes in their oxygen content (2–3 min) while maintaining their chemical properties. The cyclic redox reaction revealed that Sr(Mn1−x Ni x )O3 exhibits excellent structural stability and provides a continuous oxygen supply during redox reactions. Good oxygen capacity was maintained during the cycling hydrogen combustion tests. These new perovskite-type materials were characterized using scanning electron microscopy (SEM) and X-ray diffraction (XRD) measurements and by surface area (BET), particle size distribution (PSD) and melting behavior analyses. The Sr(Mn1−x Ni x )O3 oxides exhibited high melting temperatures and small surface areas. The promising results obtained from chemical-looping combustion experiments indicate that the Sr(Mn1− x Ni x )O3 oxides are potentially useful oxygen carriers for chemical-looping combustion processes where hydrogen is one of the fuel components. [Copyright &y& Elsevier]

Abstract: Nanostructured perovskite-type Sr1− a Ce a FeO3− x , (0⩽a<0.15) powders have been prepared by citrate–nitrate smoldering auto-combustion. Their phase structure and stability, surface and morphological properties, reduction behavior and interaction with oxygen have been investigated by X-ray Powder Diffraction combined with Rietveld Analysis, 57Fe Mössbauer and X-ray Photoelectron Spectroscopies, N2-adsorption method, Temperature Programmed Reduction and Oxidation experiments. Our results reveal that citrate–nitrate auto-combustion method is effective in obtaining single phase Sr1− a Ce a FeO3− x . The Sr1− a Ce a FeO3− x structure is cubic only for a⩾0.06, while for a<0.06 remains tetragonal. Moreover, for a⩾0.06 after semi-reductive treatment under inert gas, an expanded cubic phase is obtained instead of the brownmillerite-type structure, which is known to have ordered vacancies. Stabilization of octahedral Fe3+ by cerium doping appears to be the main factor in determining the structural properties of Sr1− a Ce a FeO3− x . The highest oxygen consumption for Ce-doped SrFeO3 occurs for a=0.06. Preliminary impedance measurements show that Sr0.94Ce0.06FeO3− x has the lowest area-specific resistance. [Copyright &y& Elsevier]