Strain-Enhanced Low-Temperature High Ionic Conductivity in Perovskite Nanopillar-Array Films.

Solid oxide ionic conductors with high ionic conductivity are highly desired for oxide-based electrochemical and energy devices, such as solid oxide fuel cells. However, achieving high ionic conductivity at low temperatures, particularly for practical out-of-plane transport applications, remains a challenge. In this study, leveraging the emergent interphase strain methodology, we achieve an exceptional low-temperature out-of-plane ionic conductivity in NaBiTiO (NBT)-MgO nanopillar-array films.

Strong Local Polarization Fluctuations Enabled High Electrostatic Energy Storage in Pb-Free Relaxors.

Electrostatic energy-storage ceramic capacitors are essential components of modern electrified power systems. However, improving their energy-storage density while maintaining high efficiency to facilitate cutting-edge miniaturized and integrated applications remains an ongoing challenge. Herein, we report a record-high energy-storage density of 20.

Design of Excellent Mechanical Performances and Magnetic Refrigeration via In Situ Forming Dual-Phase Alloys.

Magnetic refrigeration technology can achieve higher energy efficiency based on the magnetocaloric effect (MCE). However, the practical application of MCE materials is hindered by their poor mechanical properties, making them challenging to process into devices. Conventional strengthening strategies usually lead to a trade-off with refrigeration capacity reduction.

Optimized Electrocaloric Refrigeration in Lead-Free NaNbO-Based Ceramics via AFE ↔ FE Phase Transition Modulation.

An outstanding challenge for eco-friendly ferroelectric (FE) refrigeration is to achieve a large adiabatic temperature change within a broad temperature range originating from the electrocaloric (EC) effect, which is expected to be realized in antiferroelectric (AFE) materials owing to the large entropy change during electric field and thermally induced phase transition. In this work, a large EC response over a wide response temperature range can be achieved slightly above room temperature via designing the phase transition of NaNbO. An irreversible to reversible AFE-FE phase transition on heating induced by the introduction of CaZrO into NaNbO plays a key role in the optimized electrocaloric refrigeration.

Local Chemical Clustering Enabled Ultrahigh Capacitive Energy Storage in Pb-Free Relaxors.

Designing Pb-free relaxors with both a high capacitive energy density () and high storage efficiency (η) remains a remarkable challenge for cutting-edge pulsed power technologies. Local compositional heterogeneity is crucial for achieving complex polar structure in solid solution relaxors, but its role in optimizing energy storage properties is often overlooked. Here, we report that an exceptionally high of 15.

Chemical Design of Pb-Free Relaxors for Giant Capacitive Energy Storage.

Dielectric capacitors have captured substantial attention for advanced electrical and electronic systems. Developing dielectrics with high energy density and high storage efficiency is challenging owing to the high compositional diversity and the lack of general guidelines. Herein, we propose a map that captures the structural distortion (δ) and tolerance factor () of perovskites to design Pb-free relaxors with extremely high capacitive energy storage.

Superior Capacitive Energy-Storage Performance in Pb-Free Relaxors with a Simple Chemical Composition.

Chemical design of lead-free relaxors with simultaneously high energy density () and high efficiency (η) for capacitive energy-storage has been a big challenge for advanced electronic systems. The current situation indicates that realizing such superior energy-storage properties requires highly complex chemical components. Herein, we demonstrate that, via local structure design, an ultrahigh of 10.

Emergence of high piezoelectricity from competing local polar order-disorder in relaxor ferroelectrics.

Relaxor ferroelectrics are known for outstanding piezoelectric properties, finding a broad range of applications in advanced electromechanical devices. Decoding the origins of the enhanced properties, however, have long been complicated by the heterogeneous local structures. Here, we employ the advanced big-box refinement method by fitting neutron-, X-ray-based total scattering, and X-ray absorption spectrum simultaneously, to extract local atomic polar displacements and construct 3D polar configurations in the classical relaxor ferroelectric Pb(MgNb)O-PbTiO.

Achieving giant electrostrain of above 1% in (Bi,Na)TiO-based lead-free piezoelectrics via introducing oxygen-defect composition.

Piezoelectric ceramics have been extensively used in actuators, where the magnitude of electrostrain is key indicator for large-stroke actuation applications. Here, we propose an innovative strategy based on defect chemistry to form a defect-engineered morphotropic phase boundary and achieve a giant strain of 1.12% in lead-free BiNaTiO (BNT)-based ceramics.