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 development of strategies to monitor the applications of pesticides is of primary importance. In the present report, two aspects of the surface‐enhanced Raman scattering (SERS) effect of the fungicide thiram were investigated: quantitative analysis using the standard addition method and the thiram adsorption mechanism onto Ag nanostructures using theoretical approach. Experimentally, SERS intensity varies linearly from 1.0 × 10−8 to 4.0 × 10−7 mol/L with thiram concentration leading to a limit of detection of 1.2 × 10−8 mol/L for the band at 560 cm−1 and 1.7 × 10−9 mol/L for 1386 cm−1. The loss of linearity (above 10−6 mol/L) was associated with changes in the Ag colloid aggregation, also indicated by complementary analyses via UV‐Vis extinction spectroscopy, dynamic light scattering, and zeta potential. The differences in the spectral profiles observed for thiram Raman powder and SERS are ascribed to S–S cleavage, leading the degraded thiram adsorbing to Ag surface not only through S atoms but also through methyl groups.

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In this work, the ferroelectric and fatigue characteristics of Au/0.5Ba(Zr 0.2 Ti 0.8 )O 3 -0.5(Ba 0.7 Ca 0.3 )TiO 3 (BCZT)/Si metal−ferroelectric−semiconductor (MFS) structures are investigated. Moreover, the effect of introducing a thin dielectric HfO 2 − Al 2 O 3 (HAO) layer with different thicknesses between the BCZT layer and the Si substrate on the ferroelectric characteristics in the metal−ferroelectric−insulator−semiconductor (MFIS) configuration is evaluated. It is evidenced that the insertion of the HAO layer with a thickness of 8 nm improves the memory window of the capacitance−voltage (C−V) curves by 106% compared to the value obtained in the MFS structure and reduces the leakage currents. Furthermore, the Au/BCZT/HAO (8 nm)/Si structure shows a remarkable remnant polarization (P r ) of 7.8 μC/cm 2 , with a coercive voltage of 1.9 V. The obtained value for P r corresponds to a six times enhancement when compared to the value obtained in the Au/BCZT/Si structure. In addition, the fatigue studies reveal that the P r obtained in the Au/BCZT/HAO/Si structure slightly decreases (3%) with continuous cycling, up to 10 9 cycles. The present work evidences that Au/BCZT/HAO/Si structures are promising for nonvolatile memory applications.

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