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Herein, the effect of the insertion of a thin dielectric HfO2:Al2O3 (HAO) layer at different positions in the Pt/0.5Ba(Zr0.2Ti0.8)O3–0.5(Ba0.7Ca0.3)TiO3 (BCZT)/Au structure on the energy storage performance of the capacitors is investigated. A high storage performance is achieved through the insertion of a HAO layer between BCZT and Au layers. The insertion of the dielectric layer causes a depolarization field which results in a high linearity hysteresis loop with low energy dissipation. The Pt/BCZT/HAO/Au capacitors show an impressive energy storage density of 99.8 J cm−3 and efficiency of 71.0%, at an applied electric field of 750 kV cm−1. Further, no significant change in the energy storage properties is observed after passing 108 switching cycles through the capacitor. The presence of resistive switching (RS) in leakage current characteristics confirms the strong charge coupling between ferroelectric and insulator layers. The same trend of the RS ratio and the energy storage performance with the variation of the architecture of the devices suggests that the energy storage properties can be improved through the charge coupling between the layers. By combining ferroelectrics and dielectrics into one single structure, the proposed strategy provides an efficient way for developing highly efficient energy storage capacitors.

The aim of this paper is to present the mechanical properties of tungsten laminate pipes made of tungsten foil and to discuss their use in innovative high temperature energy conversion systems.Tungsten is the metal with the highest melting point of all metals and would therefore be an excellent fit for high temperature applications. But tungsten has one major drawback which is its low fracture toughness at room temperature (RT) or its high brittle-to-ductile transition 2 temperature (BDTT). However, one of the extraordinary properties of tungsten is that by cold working the BDTT can be shifted to lower temperatures. At the extreme, this results in a tungsten foil with a BDTT below -120°C combined with a RT fracture toughness of 70 MPa m 1/2 .By rolling up and joining a tungsten foil, tungsten laminate pipes can be synthesized that can dissipate at least 20 J in a Charpy impact test at RT and survive a burst test at RT at 1000 bar without any residual damage. The technical maturity of these W laminate pipes is approved by high heat flux tests performed at the Plataforma Solar de Almería, Spain, as well as at the