Introducing controlled electrical homogeneity can be an effective way to obtain ultrahigh energy storage density in lead-free multilayers.

The utilization of antiferroelectric (AFE) materials is thought to be an effective approach to enhance the energy density of dielectric capacitors. However, the high energy dissipation and inferior reliability that are associated with the antiferroelectric-ferroelectric phase transition are the main issues that restrict the applications of antiferroelectric ceramics. Here, simultaneously achieving high energy density and efficiency in a dielectric ceramic is proposed by combining antiferroelectric and relaxor features. Based on this concept, a lead-free dielectric (Na Bi )TiO -x(Sr Bi )TiO (NBT-xSBT) system is investigated and the corresponding multilayer ceramic capacitors (MLCCs) are fabricated. A record-high energy density of 9.5 J cm , together with a high energy efficiency of 92%, is achieved in NBT-0.45SBT multilayer ceramic capacitors, which consist of ten dielectric layers with the single-layer thickness of 20 µm and the internal electrode area of 6.25 mm . Furthermore, the newly developed capacitor exhibits a wide temperature usage range of -60 to 120 °C, with an energy-density variation of less than 10%, and satisfactory cycling reliability, with degradation of less than 8% over 10 cycles. These characteristics demonstrate that the NBT-0.45SBT multilayer ceramic is a promising candidate for high-power energy storage applications.

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The Gerson-Marshall (1959) relationship predicts an increase in dielectric breakdown strength (BDS) and therefore, recoverable energy density (Wrec) with decreasing dielectric layer thickness. This relationship only operates however, if the...

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The (Nb + In) co-doped TiO2 ceramics recently attracted considerable attention due to their colossal dielectric permittivity (CP) (∼100,000) and low dielectric loss (∼0.05). In this research, the 0.5 mol. % In-only, 0.5 mol. % Nb-only, and 0.5–7 mol. % (Nb + In) co-doped TiO2 ceramics were synthesized by standard conventional solid-state reaction method. Microstructure studies showed that all samples were in pure rutile phase. The Nb and In ions were homogeneously distributed in the grain and grain boundary. Impedance spectroscopy and I-V behavior analysis demonstrated that the ceramics may compose of semiconducting grains and insulating grain boundaries. The high conductivity of grain was associated with the reduction of Ti4+ ions to Ti3+ ions, while the migration of oxygen vacancy may account for the conductivity of grain boundary. The effects of annealing treatment and bias filed on electrical properties were investigated for co-doped TiO2 ceramics, where the electric behaviors of samples were found to be susceptible to the annealing treatment and bias field. The internal-barrier-layer-capacitance mechanism was used to explain the CP phenomenon, the effect of annealing treatment and nonlinear I-V behavior for co-doped rutile TiO2 ceramics. Compared with CaCu3Ti4O12 ceramics, the high activation energy of co-doped rutile TiO2 (3.05 eV for grain boundary) was thought to be responsible for the low dielectric loss.

High fat diet (HFD) treated mouse is widely used as experimental animal model for hyperlipidemia and hyperglycemia study. Many factors contribute to establish animal model that meant to simulate high fat and glucose diet induced phenotypes. In the present study, four strains of experiment mouse treated by HFD were used to explore the impact of mouse strain on lipid profile, glucose level, and major inflammation cytokines. HFD fed Kunming and ICR mouse gained significantly higher body weight than control which was not shown by C57BL/6 and BALB/c mouse. All four strains fed by HFD has heavier liver and adipose tissue than control ones. Obvious fat droplets and enlarged adipose cells were observed in obese mouse of four strains. Additionally, obese mouse showed typical response to glucose and insulin load in OGTT and ITT. Serum TC, LDL-c, and TC/HDL-c ratio, but not TG, increased in all four strains. Major inflammatory cytokines and insulin level showed little changes in obese mouse as well (p<0.05) The present study could provide basic information for diet induced obesity developed by four commonly used experimental mouse strains.

An electrostatic capacitor has been widely used in many fields (such as high pulsed power technology, new energy vehicles, etc.) due to its ultrahigh discharge power density. Remarkable progress has been made over the past 10 years by doping ferroelectric ceramics into polymers because the dielectric constant is positively correlated with the energy storage density. However, this method often leads to an increase in dielectric loss and a decrease in energy storage efficiency. Therefore, the way of using a multilayer structure to improve the energy storage density of the dielectric has attracted the attention of researchers. Although research on energy storage properties using multilayer dielectric is just beginning, it shows the excellent effect and huge potential. In this review, the main physical mechanisms of polarization, breakdown and energy storage in multilayer structure dielectric are introduced, the theoretical simulation and experimental results are systematically summarized, and the preparation methods and design ideas of multilayer structure dielectrics are mainly described. This article covers not only an overview of the state-of-the-art advances of multilayer structure energy storage dielectric but also the prospects that may open another window to tune the electrical performance of the electrostatic capacitor via designing a multilayer structure.