Changjian Li

Lone-pair-induced local free volume in layered Bi _1.9 Te _1.1 O _5.05 stabilizes interstitial oxygen and enables two-dimensional oxide-ion transport. This design delivers an oxide ion conductivity of 1.41 × 10 ⁻³ S cm ⁻¹ at 650 °C, providing a new strategy for developing interstitial oxide-ion conductors.

The exponential surge in demand for high‐efficiency, low‐latency data processing has created an urgent need for “more‐than‐Moore” strategies to enable high‐throughput computing. Ternary logic offers inherent advantages in data density, interconnection complexity, and computational throughput, but existing implementations are overly complex and rely on multiple binary transistors combined with additional components to achieve ternary states. This paper presents a ternary field‐effect transistor using antiferroelectric gating, which provides distinct ternary conduction states at the single‐transistor level that are robust and dynamically reconfigurable. A simple inverter based on a single ternary transistor is also demonstrated, which reduces transition time by 82% compared with a much more complex complementary metal‐oxide‐semiconductor device. Antiferroelectric field‐effect ternary transistors may pave the way for broad adoption of ternary logic systems.

Inspired by surface functionalization in perovskite exsolution catalysts, planar defects outperform low-dimensional defects in shaping nanoparticle (NP) exsolution behavior. However, their specific impact remains elusive owing to controlled synthesis challenges and entangled coexisting material features. We fabricated Ruddlesden–Popper (RP) fault-engineered LaNi0.5Fe0.5O3 film through a dual modulation strategy, and combined advanced electron microscopy, spectroscopy and electrochemical tests for systematic investigation. Moderate RP faults induce lattice perturbation and charge redistribution, creating facile and directional diffusion pathways to optimize surface metallic NP exsolution. The upshifted d-band center of the improved surface area yields 101.2 mA cm–2 oxygen evolution reaction (OER) current density at 1.6 V (∼950% higher than the defect-free counterpart) and a 67 mV dec–1 Tafel slope. However, excessive RP faults disrupt the long-range lattice order, hindering surface NP exsolution and lowering OER activity. This work reveals the RP fault-NP exsolution coupling mechanism, guiding rational design of high-performance exsolution electrocatalysts.

While non-trivial spin-orbit coupling (SOC) was predicted early in high-temperature cuprate superconductors (HTCS), its precise role and microscopic consequences remain unresolved. This challenge is primarily hindered by the lack of suitable detection methods. Here we report a significant electrical magnetochiral anisotropy (EMCA) in an archetypal high-temperature cuprate superconductor NdBa₂Cu₃O_7-δ, which is ascribed to the SOC effect under inversion and time-reversal symmetry violations in HTCS. Notably, a peculiar angular dependence of EMCA on the magnetic field orientation is observed, where an unprecedented higher-order EMCA effect is discovered. Based on Ginzburg-Landau theory analysis, the higher-order EMCA effect is intrinsically linked to magnetic-field-induced finite-momentum pairing states in HTCS. Our findings provide crucial insights into the exotic physics associated with SOC in HTCS, and pave the way for exploring high-temperature superconducting quantum electronics.

Metal–organic framework (MOF) pyrolysis is widely used to produce functional nanomaterials, yet it is still commonly regarded as a simple thermal decomposition or templating process. Here, we show that a Cu(II)–1,2,3‐triazolate (trz) MOF functions as a nanoreactor in which intrinsic metal–linker chemistry governs the evolution of both phase and morphology. Strikingly, the triazole ring remains preserved throughout the pre‐pyrolysis phase transitions that lead to the formation of Cu atomic clusters. These highly reactive Cu clusters and the preserved triazolate are essential for the subsequent formation of metal nitride, as they enable efficient nitridation at an unusually low temperature. Without introducing any external nitrogen source, the Cu clusters react with NH ₃ released from linker decomposition, leading to the formation of Cu ₃ N rather than crystallization into metallic Cu particles. By combining in situ and ex situ characterization, we show that copper, nitrogen species, and the carbonizing matrix evolve sequentially rather than independently. As a result, Cu ₃ N is selectively stabilized over metallic Cu within a fibrous N‐doped carbon network. Beyond offering a self‐nitridation route to Cu ₃ N, this work highlights the critical role of transient intermediates in directing MOF pyrolysis outcomes and redefines MOF pyrolysis as a chemically interactive process.

Metal–organic framework (MOF) pyrolysis is widely used to produce functional nanomaterials, yet it is still commonly regarded as a simple thermal decomposition or templating process. Here, we show that a Cu(II)–1,2,3‐triazolate (trz) MOF functions as a nanoreactor in which intrinsic metal–linker chemistry governs the evolution of both phase and morphology. Strikingly, the triazole ring remains preserved throughout the pre‐pyrolysis phase transitions that lead to the formation of Cu atomic clusters. These highly reactive Cu clusters and the preserved triazolate are essential for the subsequent formation of metal nitride, as they enable efficient nitridation at an unusually low temperature. Without introducing any external nitrogen source, the Cu clusters react with NH ₃ released from linker decomposition, leading to the formation of Cu ₃ N rather than crystallization into metallic Cu particles. By combining in situ and ex situ characterization, we show that copper, nitrogen species, and the carbonizing matrix evolve sequentially rather than independently. As a result, Cu ₃ N is selectively stabilized over metallic Cu within a fibrous N‐doped carbon network. Beyond offering a self‐nitridation route to Cu ₃ N, this work highlights the critical role of transient intermediates in directing MOF pyrolysis outcomes and redefines MOF pyrolysis as a chemically interactive process.

Bi2O2Se (BOS), due to its high carrier mobility, strong spin–orbit coupling effect, and air stability, has garnered significant attention in the field of 2D semiconductors for next-generation electronics, spintronics, and photodetector and memristor applications. Currently, BOS is dominantly prepared by chemical vapor deposition and molecular beam epitaxy methods, while pulsed laser deposited (PLD) BOS films are less explored, and the film quality is significantly inferior compared to other preparation methods. In this work, we systematically investigated the PLD growth conditions and defined a growth window (deposition temperature of 340–370 °C and energy density lower than 0.9 J/cm2) for BOS. Atomically flat, high-quality epitaxial and stoichiometric BOS thin films are achieved. Atomic-scale structural and elemental analyses show a unique interfacial region of 2-unit-cell-thick Sr1−xBixTiO3+δ, which accommodates the interfacial strain. The epitaxial BOS film exhibited a Hall mobility of 3103 cm2 V−1 s−1 at 2 K and displayed Shubnikov–de Haas (SdH) oscillations between 2 and 6 K. This observation of SdH oscillations, the first reported for PLD-grown BOS, underscores the high quality of the film. Our work demonstrates the feasibility of enhancing the electrical transport properties of PLD-grown BOS, thereby facilitating future studies in nanoelectronics.

Layered Indium phosphorus trichalcogenides (In _4/3 P ₂ X ₆ ) have received significant attention due to their ordered indium vacancies and stacking‐dependent properties, enabling applications in electronics, catalysis, and energy storage. However, the vacancy‐governed stacking polytypes and atomic structures in In _4/3 P ₂ X ₆ remain elusive. Moreover, the facile reconstruction of the indium vacancies upon external stimulus makes their direct visualization challenging. Here, a low‐dose aberration‐corrected scanning transmission electron microscopy (STEM), four‐dimensional STEM (4D‐STEM) techniques, and density functional theory (DFT) are employed to systematically explore the atomic structure of In _4/3 P ₂ X ₆ and the magnetic properties of doped In _4/3 P ₂ X ₆ . The indium vacancies with glide‐reflection symmetric ordering in In _4/3 P ₂ X ₆ are resolved at the atomic scale, driving armchair‐type interlayer gliding with an unconventional step in In _4/3 P ₂ Se ₆ and zigzag‐type gliding in In _4/3 P ₂ S ₆ , yielding ABC and nearly‐ABC stacking polytypes, respectively. DFT calculations reveal that both gliding modes are energetically favorable, with their distinctions arising from the ligand‐modulated interlayer charge distributions. Besides, filling the indium vacancies with magnetic dopants induces tunable magnetic ordering in In _4/3 P ₂ X ₆ , and also drives a structural transition to an MPX ₃ ‐like phase and a non‐magnetic paramagnetic (PM)−FM transition. This study sheds light on vacancy‐governed structure in In _4/3 P ₂ X ₆ and highlights it as an excellent matrix for designing novel functional 2D magnets via doping engineering.

The sensitivity and reliability of piezoelectric accelerometers heavily rely on the piezoelectric coefficient and temperature stability of their core components. However, the inherent nature of polycrystalline phase boundaries in lead-free piezoceramics poses a significant challenge in simultaneously achieving excellent comprehensive properties. This study proposes a co-fired multilayer piezoceramics architecture to achieve nearly 10-fold increase in piezoelectric coefficient (from 165 pC/N of bulks to 1568 pC/N of multilayer piezoceramics) and significantly enhanced temperature stability in potassium sodium niobate based ceramics, breaking the long-standing trade-off relationship between the two core parameters. The superior temperature stability is achieved by introducing residual thermal stresses in the inner electrode and ceramic layers within the multilayer structure. The introduced internal stress both stabilizes the lower symmetry phases and restrained domain switching. The prototype acceleration sensors were developed and the multilayer piezoceramics device shows a good linearity and higher sensitivity compared to bulk ceramics, with only a slight property fluctuation with temperature increases. This work establishes a feasible strategy for synergistically optimizing piezoelectricity and temperature stability in lead-free ceramics, extending their sensor application for structural health monitoring.

Integrating sensing functions into memristors is promising to realize in‐sensor computing with unpreceded energy efficiency and minimized latency. Strain‐sensitive memristors gradually draw attention in neuromorphic tactile sensing applications, but still face the sensitivity‐response time tradeoff dilemma. Here, we demonstrate that antiphase boundaries (APBs) in thin‐film structures function as mechanically gated vertical ion channels in a strain‐sensitive neuromorphic memristor, which can achieve high sensitivity (strain gauge factor of 1.7 × 10 ⁴ ) and rapid response (≤3 ms) while exhibiting synaptic plasticity. Through atomic‐scale scanning transmission electron microscopy (STEM), electron energy loss spectroscopy (EELS), and nanoscale conducting atomic force microscopy (C‐AFM), we confirm APBs as preferential oxygen vacancy migration paths, whose conductivity is dynamically modulated by electrical and mechanical stimuli synchronous and directly. Excellent electrically (25500% on/off ratio at −7 V) and mechanically tunable conductive (enhanced 15167% with ∼3.3 µN force) behavior along APBs pillars is clearly observed. While synapse‐like information processing functions are also further demonstrated with APBs pillars, and a high image classification accuracy (97.7%) within 100 learning epochs is achieved in a two‐level artificial neural network via simulation. This work establishes a potential pathway for integrated sensing and computing systems for next‐generation intelligent robotics and adaptive prosthetics.