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Dielectric capacitors prepared by antiferroelectric (AFE) materials have the advantages of large power density and fast discharge ability. It has been a focus on the improvement of the recoverable energy density (Wrec) and discharge energy–density (Wdis) in the AFE ceramics. To address the above issue, optimizing the proportion of components is proposed for enhancing ceramic antiferroelectricity, ultimately improving the breakdown strength (Eb) and Wrec. In this work, an ultrahigh Wrec (14.3 J/cm3) with an excellent energy efficiency (η) of 81.1% is obtained in (Pb0.96Sr0.02La0.02)(Hf0.9Sn0.1)O3 AFE ceramic at electric field of 490 kV/cm, which is the maximum value reported in lead-based AFE ceramics fabricated by the conventional solid-state reaction method so far. The multistage phase transition induced by the electric field is observed in the polarization–electric field (P–E) hysteresis loops. Furthermore, an outstanding power density (PD) of 335 MW/cm3 and an excellent Wdis of 8.97 J/cm3 with a rapid discharge speed (102 ns) are obtained at electric field of 390 kV/cm. In addition, (Pb0.96Sr0.02La0.02)(Hf0.9Sn0.1)O3 ceramics also possess an excellent thermal and frequency stability. These exceptional properties indicate that (Pb0.98−xSrxLa0.02)(Hf0.9Sn0.1)O3 ceramics are a potential candidate for pulsed power devices and power electronic devices. [ABSTRACT FROM AUTHOR]

Beginning with the revolutionary discovery of graphene, researchers have delved into numerous van der Waals (vdW) materials known for their exceptional electrical, optical, thermal and mechanical properties, significantly widening the boundaries of our manipulation and understanding of the physical world at the nanoscale. CuInP2S6 (CIPS), as one of the emerging two-dimensional (2D) vdW materials, has garnered considerable attention due to its vdW layered structure and room-temperature ferroelectricity. In recent years, CIPS holds broad application prospects in neuromorphic computing, artificial visual systems and memory devices, and has aroused extensive research interest in materials science and optoelectronics. In this review, we summarized the diverse properties of CIPS and the different microscopic origins of memristive behavior, and then introduced several devices based on CIPS with different design structures. Finally, the challenges that still exist in the device application are discussed, as well as possible directions for further exploration of the material in the future. [ABSTRACT FROM AUTHOR]

Negative photoconductive devices exhibit a significant reduction in conductivity under illumination, enabling high-contrast optical modulation and promising great potential in optics. In this study, an ITO/BFCO/TiO2/FTO device was simply fabricated through a synergistic application of sol-gel and magnetron sputtering techniques. Interestingly, the ferroelectric polarization can be reversibly modulated by a low bias voltage in the ITO/BFCO/TiO2/FTO device, thereby exhibiting bipolar voltage dependent reversible behavior of positive and negative photoconductivity. This mechanism has been discussed, where the combined effect of illumination and applied voltage induces internal polarization reversal in Bi2FeCrO6, leading to a transition in the resistance state from low to high. This transition results in an elevation of the energy band, thereby impeding the migration of charge carriers. Additionally, femtosecond laser transient absorption spectroscopy reveals redshift in the initial absorption peak, indicating changes in the band structure induced by illumination, crucial for understanding carrier dynamics in a non-equilibrium state. [ABSTRACT FROM AUTHOR]

Multiferroic materials have important research significance in the fields of magnetic random-access memory, ferroelectric random-access memory, resistive random-access memory, and neuromorphic computing devices due to their excellent and diverse physical properties. In this work, a solution of Bi2FeMnO6 was prepared using a solution-based method, and an Au/Bi2FeMnO6/TiO2 heterostructure device was fabricated on a Si substrate. X-ray diffraction and transmission electron microscopy data indicate that the Bi2FeMnO6 films have hexagonal R3c symmetry structures. The Bi2FeMnO6 film exhibits ferroelectricity with a fine remanent polarization. In addition, the Bi2FeMnO6-based devices have excellent switching ratios of 6.37 × 105. A larger switching ratio can provide a multi-resistance state for the device, which is beneficial for the simulation of synapses. Hence, it effectively emulates excitatory postsynaptic currents, paired-pulse facilitation, and long-term plasticity of synapses and achieves recognition accuracy of 95% in neuromorphic computing. We report a promising material for the development of various nonvolatile memories and neuromorphic synaptic devices. [ABSTRACT FROM AUTHOR]