It is common that the as-sintered bulk ceramics or powders undergo mechanical and/or heat treatment for further investigating the structure or properties. However, if their structures change during these procedures, it would mislead their structure-properties relation and subsequently lead to the wrong design of the desired ceramic products. In this work, we reported the mechanical/heat treatment effect on the structures of AgNbO3-based antiferroelectric/ferroelectric (AFE/FE) materials. The results revealed that the structure of AgNbO3-based systems with chemical compositions close to/in the AFE/FE phase boundary strongly depends on the history of polishing/grinding and/or annealing processing. Manual polishing/grinding (or milling) ceramic bulk/powders can induce a phase transition from AFE(Pbcm) to FE(R3c), and the transition can be reversed via the heat treatment, which is intimately related to a temperature-driven phase transformation having a metastable AFE phase. Our finding thus provides new insight into phase transitions in AgNbO3-based systems, suggesting that the proper parameters of processing need to be considered to enable the development of an understanding of structure-property relationships in ceramic materials.

The bulk photovoltaic (BPV) effect in ferroelectric (FE) materials enables the direct conversion and exchange of information between the optical and electrical domains in applications such as photonic computing and photodetection. Although the above-bandgap open-circuit voltage in the FE BPV effect permits a much higher photovoltage in comparison to the semiconductor PV effect, there are still challenges. For example, when requiring a reduction in the thickness of materials for device fabrication and integration, the photovoltage tends to diminish. In this paper, we demonstrate that interfacial strain-induced structurally orientated domains can enhance the BPV effect of FE films, with a 50 nm thick BaTiO3 film, grown on a silicon substrate, shown to exhibit an open-circuit photovoltage of over 1.07 V - the highest reported value for traditional ferroelectric films under 300 nm thickness. This work offers new insights into the role of crystal orientation in FE BPVs as well as points to the potential use of ferroelectric materials in various photoelectrical applications, such as high-speed data processing and transmission in photonic computing systems, when integrated with silicon.

Oxide semiconductors have emerged as common channel materials in transistors and hold promise for next-generation electronics, yet achieving high mobility typically requires costly vacuum-based techniques. Here, ultrathin (5 nm) indium native oxide (InOx) prepared by ambient-air liquid-metal printing (LMP) at a low temperature (250 °C) is applied as a semiconducting channel in a field-effect transistor (FET). The resulting InOx is found to be polycrystalline, with large lateral grains that extend vertically throughout the film thickness. InOx FETs in a transfer length method configuration demonstrate a high conductivity mobility (μCON) of 125 cm2 V-1 s-1, with systematic analysis of contact resistance confirming the potential for channel length scaling. Integration with atomic-layer-deposited gate dielectrics further reveals excellent compatibility; for instance, an InOx FET integrated with HfO2 exhibits a high field-effect mobility (μFE) of 107 cm2 V-1 s-1, an on/off current ratio (ION/IOFF) of >107, a subthreshold swing (SS) of 204 mV dec-1, and a gate leakage of <10-6 A cm-2, while maintaining stable performance over 104 endurance cycles without degradation. Postfabrication oxygen plasma treatment is applied to achieve enhancement-mode operation, and a depletion-load inverter is demonstrated, exhibiting a voltage gain of 69.8 V/V. These results demonstrate the great potential of LMP InOx as a semiconducting channel in high-performance and power-efficient transistors for next-generation oxide electronics.

3D perovskite nanocrystals have emerged as promising fillers incorporated into PVDF films for flexible piezoelectric nanogenerators (PENGs). Nevertheless, their stability issues, such as moisture sensitivity and thermal degradation, cause reduced long-term reliability and durability of perovskite-based PENGs, hindering their practical application. Herein, we demonstrate the high-performance PENGs using in situ grown 2D perovskite (PEA2MA2Pb3Br10) nanocrystals (2D PSK NCs) in the PVDF matrix. The interaction between 2D PSK NCs and PVDF dipoles enhances the electroactive phase content to 86.35% and the piezoelectric coefficient to 35.16 pm/V of the composite films. Therefore, the unpolarized 17.3 wt.% 2D PSK NCS@PVDF-based PENG demonstrates outstanding piezoelectric outputs with an ultra-high voltage of 66.54 V and a decent current density of 1.166 µA/cm2 under periodic vertical impact, corresponding to 2.74- and 7.29-fold increases over the pure PVDF-based device. Notably, the PENG also performs under different light conditions. The addition of 2D PSK NCs absorbed photons leads to enhanced piezoelectric output in sunlight. Additionally, the composite films display remarkable hydrophobicity and mechanical durability, sustaining stable operation for over 12000 continuous impact cycles. The energy generated from the PENG can charge capacitors and power small electrical devices, such as a calculator and commercial light-emitting diodes.

The strategic selection of alkali metal nitrates in molten salt synthesis critically governs the structural evolution and electrocatalytic performance of iridium oxide hydrate (IrOx·nH2O) catalysts for oxygen evolution reaction (OER). While NaNO3-mediated synthesis has shown superior catalytic activity, we systematically investigated LiNO3 and KNO3 as alternative molten salt media to elucidate structure-property relationships. X-ray pair distribution function (PDF) analysis revealed that the LiNO3-derived catalysts retained a significant amount of unreacted amorphous IrCl3 precursor, yielding the poorest electrocatalytic efficiency. This incomplete conversion is attributed to the exceptionally high viscosity of molten LiNO3, which severely restricts precursor diffusion and crystal growth. In contrast, KNO3-mediated synthesis produced a local structure that can be described as a mixture of hollandite- and rutile-type motifs, delivering intermediate performance. The emergence of rutile-type IrO6 octahedral connectivity due to localized thermal hotspots arising from the lower thermal conductivity of molten KNO3 relative to NaNO3 promotes temperature-induced phase transformations. These findings establish a fundamental correlation between the physicochemical properties of molten salts and catalyst architecture, demonstrating that NaNO3-facilitated hollandite-type local structures optimize ion transport pathways and electrocatalytic activity. This work highlights the critical importance of rational molten salt selection in the design of high-performance OER catalysts.

As promising candidates for next-generation energy storage devices in electrical and electronic systems, lead-free multilayer ceramic capacitors face increasingly high performance requirements. To counteract the usual trade-off between energy storage density and efficiency, we here propose a high-entropy design that directly harnesses diverse oxide symmetries to targetedly engineer competing orders and tune the composition into the crossover region between relaxor ferroelectric and superparaelectric states. Atomic-scale structural analysis reveals high-entropy ceramic develops pronounced local polarization fluctuation and dispersed oxygen octahedral rotations, which enhance relaxor behavior and reduce switching barrier. Consequently, superior recoverable energy density of 20.64 J cm-3 and high efficiency of 94.2% are obtained in our designed high-entropy Bi0.5Na0.5TiO3-based multilayer ceramic capacitors, along with excellent thermal/anti-fatigue stability and charge-discharge capabilities. This work provides a transferable strategy to engineer competing orders in lead-free dielectric materials and successfully achieves high-entropy multilayer ceramic capacitors with superior energy storage performance.

Tetragonal tungsten bronze (TTB) ceramics have emerged as promising candidates for dielectric energy storage due to their intrinsic multi-site architectures. However, the limited energy storage performance achieved so far remains insufficient for advanced electronic and pulsed power applications. Here, we propose a targeted polar-entropy regulation strategy via minor multi-element substitution at the polar-active B-sites, enabling precise modulation of polar displacements and weakened coupling among polar nanoregions. Atomic-scale characterization reveals site-dependent structural responses, which collectively reshape local polarization configurations and dipolar correlations. As a result, we demonstrate the feasibility of TTB ceramics for state-of-the-art multilayer energy-storage device applications, achieving an outstanding recoverable energy density (Wrec) of 17.6 J·cm-3 with a high efficiency of 96.8%, corresponding to a high figure of merit (WF) of 550. Moreover, excellent thermal stability (ΔWrec ≤ 2.0%) is achieved, and a highest Wrec of 15.0 J·cm-3 is maintained over a wide temperature range (-40 to 125 °C). This work offers new insights into polarization regulation and provides an effective pathway for developing high-performance energy storage dielectric capacitors.

The solar-powered CO2 conversion via the photocatalysis route offers a sustainable pathway toward carbon neutrality while mitigating energy/environmental pressure. Nevertheless, the selective and efficient conversion of CO2 via photoreduction to C2 products remains a formidable challenge. Here, we engineered a dual-single-atom photocatalyst by controllably embedding Pd and Cu single atoms into a TiO2 matrix. The optimized catalyst (Cu0.5Pd0.5/TiO2) exhibits the outstanding yield (119.2 µmol/gcat) and selectivity (84.8%) for acetic acid production from CO2 photoreduction, performed in seawater and in a photothermal-aided reactor. Various in situ/ex situ characterizations were employed to investigate atomic-level structure-performance correlation and reaction mechanism in practical condition. In situ x-ray photoelectron spectroscopy, in situ atomic force microscopy-Kelvin probe force microscopy, transient-state surface photovoltage, and in situ electron paramagnetic resonance (EPR) collectively indicate that loading Pd and Cu single atoms onto TiO2 apparently accelerates charge kinetics. This modification results in increased photogenerated electrons for CO2 reduction, facilitating C─C coupling and hydrogenation reactions. Additionally, in situ infrared (IR) spectroscopy and theoretical computations affirm the pivotal function of Pd single atoms for lowering the energy barrier to form the *OCCO intermediate, apparently improving selectivity for acetic acid production. Overall, our work presents an innovative approach to tackle kinetic and thermodynamic challenges for light-induced CO2-to-C2 conversion.

High-entropy metal-organic frameworks are commonly realized within framework families that are already accessible as isostructural single-metal analogues. As a result, multimetal incorporation usually preserves pre-existing topologies rather than generating structurally distinct frameworks. In zeolitic imidazolate frameworks (ZIFs), this challenge is amplified by strong metal-imidazolate preference, rendering structurally distinct high-entropy ZIFs particularly elusive. Here we report an entropy-assisted coligation strategy that enables the synthesis of a genuinely distinct high-entropy zeolitic imidazolate framework (HE-ZIF), [Fe0.26Ni0.23Mn0.26Co0.2Zn0.05(C2O4)(Hmim)2]n from an equimolar five-metal system. In contrast to conventional ZIF chemistry, this HE-ZIF does not inherit the tetrahedral topology of known single-metal ZIFs. Instead, three-dimensional electron diffraction resolves a new monoclinic structure featuring multimetal nodes, reduced metal-imidazolate coordination, and enhanced linker flexibility. Synchrotron powder diffraction further confirms that this distinct framework is retained as the bulk single phase. Residual coordination maps derived from density functional theory calculations show that increasing configurational complexity progressively balances metal-ligand coordination preferences, enabling coligation inaccessible in low-entropy systems. This design extends to additional multimetal compositions. As a proof of concept, incorporation of HE-ZIF into a perfluorosulfonic acid matrix improves proton conductivity by more than 55% relative to Nafion at 70 °C, demonstrating functional utility of the resulting coordination environment.

Photocatalytic conversion of methane (CH4) to liquid oxygenates under mild conditions remains challenging due to the need to simultaneously regulate C–H bond activation, oxygen activation, C–C coupling, and over-oxidation. This paper reports a Ru-modified TiO2 photocatalyst (0.5RT) that integrates isolated Ru atoms, neighbouring Ru configurations, and possible subnanometric RuOx–like clusters on TiO2. Advanced structural characterization techniques such as Aberration-corrected HAADF-STEM and X-ray absorption spectroscopy reveal that these Ru species are highly dispersed and primarily coordinated by oxygen on TiO2. In this CH4/O2/H2O system, Ru–O–Ti atomic sites promote interfacial charge transfer and CH4 polarization, while RuOx-like clusters enhance reactant adsorption and promote O2 activation. Additionally, neighbouring Ru configurations facilitate the local coexistence of methyl-related intermediates and oxygenated C1 intermediates, thereby promoting acetate formation. Therefore, 0.5RT produces liquid oxygenate production yield of 668 μmol gcat-1 acetic acid (CH3COOH) and 653 μmol gcat-1 formic acid (HCOOH) after 4 h of irradiation, with a CH3COOH/HCOOH molar yield ratio of 1.02. Mechanistic insights from in situ spectroscopies and density functional theory calculations reveal that Ru atomic sites promote C–H polarization, whereas RuOx-like clusters promote O2 adsorption and O–O bond weakening. Their close proximity favours C–C coupling toward CH3COOH formation.

Photocatalytic oxygen reduction offers a sustainable route to hydrogen peroxide (H2O2) production; however, rapid charge-carrier recombination and sluggish oxygen-reduction reaction (ORR) kinetics remain the primary bottlenecks. Herein, an atomically correlated phosphorus-sulfur co-doped graphitic carbon nitride (g-C3N4), referred to as P-S:gCN, is demonstrated to enable efficient H2O2 photogeneration in O2-saturated water without sacrificial agents. Introducing atomically correlated P-S sites within the heptazine framework creates an asymmetric charge distribution that suppresses trap-mediated recombination and promotes efficient charge separation. These coupled heteroatom sites also enhance oxygen adsorption and activation on the catalytic surface, directing the reaction through the selective 2e- ORR pathway to increase H2O2 generation. Under visible-light irradiation, P-S:gCN achieves an apparent quantum yield of 6.80% at 420 nm and a solar-to-chemical conversion efficiency of 0.49% in pure water. Combined experimental and theoretical evidence reveals that atomically correlated P-S sites regulate charge transport, suppress recombination, and promote selective 2e- ORR more effectively than isolated dopants. This atomically correlated dual-site engineering opens avenues for tuning charge transport, electronic structure, and the stability of reaction intermediates in metal-free photocatalytic systems.

Multilayer ceramic capacitors (MLCCs) are promising candidates for miniaturizing advanced electronic systems, owing to their high-power density and rapid discharge capabilities. However, simultaneously achieving high energy density and near-zero energy loss remains a long-standing challenge, hindering their application potential as next-generation energy-storage devices. Here, we propose a bottom-up self-assembly strategy within a disordered (Sr0.2Ca0.2Pb0.2Na0.2La0.2)TiO3 high-entropy ceramic matrix to construct a nanodomain configuration. The high-entropy design guarantees a locally compositional inhomogeneous platform with fully lowered energy barrier for dipole switching, and the subsequent substitution of strong polar Bi effectively facilitates the progress of nanodomain assembly. The synergistic regulation of lattice structure and anisotropic domain configuration gives rise to relaxor antiferroelectric-like polarization behavior, simultaneously enabling high polarization intensity and fast dipole switching. Consequently, a concurrent breakthrough with a high energy density of 24.7 J cm-3 and an ultrahigh efficiency of 96.5% is achieved in the antiferroelectric-like high-entropy superparaelectric MLCCs. This work establishes a new opportunity for manipulating polarization profiles and designing high-performance energy storage dielectrics.

The development of multilayer ceramic capacitors (MLCCs) with high energy storage performance (ESP) is crucial for keeping pace with the ongoing trend toward miniaturization and integration in next-generation pulsed-power systems. Nevertheless, current research strategies of tailoring device performance based on bulk ceramic properties typically involve premature polarization saturation and limit the potential for performance breakthroughs in MLCCs. To address this issue, we construct a novel polarization configuration comprising polar clusters embedded within a glass-like matrix. This configuration successfully enables high-polarity near-linear characteristics under high electric fields, avoiding the energy density limitations imposed by premature polarization saturation in conventional relaxors. As a result, the fabricated MLCCs exhibit ultrahigh ESP with a recoverable energy density of 24.8 J cm-3 and an efficiency of 92.4%, along with exceptional reliability and discharge characteristics, demonstrating enormous application potential. This work highlights the superiority of developing high-polarity near-linear dielectrics over existing strategies for achieving ultrahigh-ESP MLCCs and proposes a feasible approach via high-entropy engineering to construct a self-assembled glass-like matrix and polar clusters.

The catalytic conversion of bioethanol to ethylene (C2H4) and acetylene (C2H2) offers a transformative approach to sustainable production of two industrial cornerstones for organic compound and polymer syntheses, thereby offering significant economic and environmental advantages. In contrast, current methods for the synthesis of these C-2 hydrocarbons rely on energy- and carbon-intensive processes that require high temperatures and pressures. The present work addresses these limitations with a novel, low-energy, bioethanol-conversion strategy operating at room temperature and ambient pressure using sono-piezo-photocatalysts. A novel heterostructure of graphene oxide fragments (GO) and sodium bismuth titanate (NBT) within a core-shell microstructure achieved outstanding C2H4 and C2H2 production rates of 134.1 and 55.5 mu mol/g/h, respectively. The conversion mechanism is driven by (1) bubble collapse during ultrasound irradiation, generating localized high temperatures (approximate to 4000 K) and pressures (approximate to 100 MPa), and (2) piezo-photocatalytic tuning of GO/NBT by enhanced charge separation and transfer. DFT simulations revealed detailed sono-piezo-photocatalytic conversion pathways, showing significant reductions in energy barriers for C2H4 (22.0 kcal mol(-1)) and C2H2 (48.0 kcal mol(-1)) formation. These findings emphasize the critical role of the catalyst in cleaving both C & horbar;H and C & horbar;O bonds effectively, leading to the desired product formation.

Threshold switching and negative differential resistance in V(3)O(5 )are assisted by a thermally induced insulator-metal transition that occurs at 420 K and provide the basis for fabricating a scalable relaxation oscillator. This study presents a detailed investigation of the dynamics of two capacitively coupled V3O5 oscillators, showcasing their potential for neuromorphic computing and nonlinear signal processing. The coupled oscillators exhibit rich synchronization dynamics, broadly falling within three distinct synchronization regimes: (i) no coupling, where oscillators operated independently; (ii) weak coupling, featuring phase-tuning and higher-order synchronization; and (iii) strong coupling, associated with out-of-phase and burst synchronization. Phase-tuning in the weak coupling regime enables precise control of phase differences, supporting phase-based information encoding, while burst synchronization, emerging under strong coupling with a slow oscillator and a fast oscillator, enhances information transmission efficiency, mirroring biological spiking patterns. These dynamics are shown to be accurately reproduced by an LTspice model that includes thermally driven conduction in the V3O5-based threshold-switching device. These results establish V3O5 as a viable platform for developing scalable, tunable, and energy-efficient neuromorphic architectures and bioinspired signal processing systems.

Indium oxide (In2O3) is a widely used catalyst for CO2 reduction, yet its inherent properties, such as a wide band gap and low-active surface, necessitate a modification to achieve broad-wavelength absorption and enhanced surface activity. However, simultaneously achieving these goals through a single material modulation approach remains challenging. Here, we present a simple yet innovative strategy to develop a black catalyst, BixIn2-xO3-y, comprising notably low-coordinated bismuth on oxygen-defect-laden In2O3. This approach induces local structural and charge carrier changes, resulting in remarkably high visible light absorption and preeminent surface activity. In situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) confirms the spontaneous dissociation of CO2 species into CO even in the dark on the BixIn O-2-x(3-y) surface, underscoring the catalyst's enhanced activity. Compared to pristine In2O3, BixIn2-xO3-y exhibits approximately 24 times greater CO production. Characterization techniques, including extended X-ray absorption fine structure (EXAFS) and X-ray absorption near-edge structure (XANES) analyses, along with density functional theory (DFT) calculations, reveal that oxygen vacancies in the reduced sample decrease both the average coordination number of bismuth and its effective oxidation state. Our findings indicate that the unusually low-coordinated bismuth dopant preferably promotes the formation of oxygen vacancies close to bismuth (Bi-V-o) rather than near indium, which induces local structural and charge carrier changes. These Bi-V-o clusters enhance light harvesting, charge separation, and CO2 adsorption/activation/reduction. Importantly, our approach demonstrates promise for a wide range of applications, addressing key challenges in catalyst modification for CO2 reduction and offering opportunities for further advancement in this field.

The development of advanced environmentally friendly energy storage capacitors is critical to meet escalating demands of pulsed power systems. However, challenges persist in enhancing both the recoverable energy density (Wrec) and efficiency (η) simultaneously. In the present study, a strategy involving domain configuration modulation, achieved by simple single rare earth ion doping, was proposed to enhance the energy-storage performance of BaTiO3. The designed Ba1-1.5xLaxTiO3 (BLT-x) ceramics exhibited an ultrahigh Wrec of 9.2 J cm-3 and η of 85.0% when x = 0.10. Furthermore, the origin of the superior performance was revealed through first-principles calculations and atomic-scale displacement analysis. The introduction of La generated intense structural fluctuations in the ordered ferroelectric domains, leading to relaxors with weakly coupled polar nanoregions and delayed saturation polarization. Such factors, combined with enhanced Eb, contributed to elongated P-E loops and ultimately ultrahigh Wrec and η. Meanwhile, the BLT-0.10 ceramic demonstrated exceptional temperature stability (-40-120 °C), frequency stability (10-250 Hz) and fatigue stability (106 cycles), along with notable charging-discharging capabilities. The present research not only provides a potential candidate for advanced pulsed power systems, but also offers a novel strategy for achieving superior energy-storage performance in perovskite ferroelectrics through single rare earth ion-doping.

Ferroelectric photovoltaics have attracted increasing attention since their discovery in the 1970s, due to their above-bandgap photovoltage and polarized-light-dependent photocurrent. However, their practical applications have been limited by their weak visible light absorption and low photoconductivity. Intrinsic modification of the material, such as bandgap tuning through chemical doping, has proven effective, but usually leads to the degradation of ferroelectricity. Recently, various nanostructures, such as multilayer heterojunctions, nanoparticles, vertically aligned nanocomposites and polar nanoregions, have been developed to enhance photovoltaic performance. These approaches enable the nanoassembly of materials in a lower-dimension manner to optimize the bulk photovoltaic effect whilst effectively preserving or even inducing ferroelectricity. This review highlights the fabrication processes of these emerging ferroelectric nanostructures and evaluates their photovoltaic performance.

Anomalous photovoltaic effect of ferroelectrics is receiving intensive research interests. However, many ferroelectric materials struggle to effectively harness the solar spectrum due to their large bandgaps. AgNbO3 has partial visible-light response, but weak photoelectric/photovoltaic performance. Here, we prepare and report the photoelectric/photovoltaic performance of Ag1-xKxNbO3 solid-solution ceramics. The results indicate that all the investigated ceramics exhibit a narrow bandgap (Eg approximate to 1.95 eV); mechanical polishing further improves lightabsorption, enhancing photoelectric response. Composition-driven improvements in photoelectric/photovoltaic performance were observed, which is closely linked to the enhanced ferroelectricity. The poling electric-field effect on photoelectric/photovoltaic performance and ferroelectric properties reveals that the open-circuit voltage (Voc) and short-circuit current (Jsc) are directly proportional to the remnant polarization until the applied field reaches 100 kV/cm. Upon illuminating the polarization-saturated ferroelectric ceramic (x = 0.07) surface, the maximum Voc (=8 V) and Jsc (=1 mu A/cm2) were achieved, which are 10 times and 35 times larger, respectively, than those of AgNbO3 ceramics.