Three-terminal memtransistors provide a promising platform for neuromorphic computing by enabling precise gate-controlled modulation of synaptic weights. Here, we demonstrate three-terminal indium–gallium–zinc oxide (IGZO)-based memtransistors incorporating composition-engineered HfAlOx (HAO) interlayers, where defect chemistry is systematically controlled through a co-sputtering approach to achieve tunable resistive switching and synaptic functionalities. By varying the HfO2 target power while maintaining a fixed Al2O3 target power, the Al/(Hf+Al) cation ratio was continuously tuned from 31.4% to 68.0%, leading to a corresponding modulation of the oxygen vacancy fraction from 24.5% to 10.6%. The composition-controlled devices exhibited bipolar resistive switching characteristics with an on/off current ratio exceeding 104. Furthermore, the IGZO memtransistors demonstrated programmable synaptic behaviors including potentiation/depression and volatile memory characteristics. A multilayer perceptron neural network trained using experimentally extracted potentiation/depression characteristics achieved a handwritten digit recognition accuracy of 89.0%. These results establish composition engineering of oxide alloys as an effective strategy for controlling defect-mediated neuromorphic functionalities and provide a CMOS-compatible pathway toward hardware-based synaptic computing systems.
Two-dimensional MXenes are promising building blocks for flexible electromagnetic interference (EMI) shielding, but their metallic-like conductivity often causes impedance mismatch and reflection-dominated shielding, generating secondary electromagnetic pollution. Achieving absorption-dominated shielding therefore requires structural design that couples composition, architecture, and service reliability. Here, based on ∼180 representative studies published mainly from 2023 to 2026, we propose a three-tier processing–structure–property–reliability framework for MXene-based flexible EMI shielding materials. At the micro scale, MXene-based functional units incorporating graphene, CNTs, magnetic, metallic, ceramic, and other nanofillers are classified by their roles in impedance matching, interfacial polarization, conductive loss, and magnetic–dielectric coupling. At the macro scale, these units are mapped onto elastomers, engineering plastics, gels, nanofibres, and functional polymers, while gradient, porous, layered, Janus, and biomimetic architectures are compared in terms of flexibility, environmental tolerance, multifunctional integration, and absorption efficiency. At the service scale, dispersion instability, interfacial debonding, and oxidative degradation are identified as key failure modes, and corresponding mitigation strategies are summarized. Finally, future priorities are discussed, including tunable shielding, impedance-matching theory, deformation-aware co-design, AI-driven inverse design, and scalable manufacturing. This review aims to provide a cross-scale design roadmap for translating MXene-based flexible EMI shielding materials from laboratory demonstrations to reliable engineering applications.
Multicomponent nanoparticles with tunable phase and composition are of great interest due to their unique electronic structures and size-dependent properties. Yet, a rapid, universal, and air-compatible route to phase-pure metal compounds remains challenging. Here, we develop a reaction microenvironment engineering-assisted pulsed laser shock (RME-PLS) strategy that expands laser-based synthesis from metals and alloys to a broad family of transition metal compound (TMC) nanoparticles, including oxides, phosphides, sulfides, and selenides. By regulating the local chemical microenvironment, this approach enables phase-selective synthesis in ambient air with high purity and short reaction time. Ligand-controlled PLS induces metal-to-oxide phase evolution, while precursor introduction of P/S/Se sources further extends the strategy to a universal RME platform. As a demonstration, carbon-coated TMC nanoparticles are used as electrocatalysts for water splitting. Notably, the laser-derived Fe2P@C reconstructs into α-FeOOH as the true active phase, which delivers exceptional catalytic performance and maintains stable operation at industrial current densities for more than 1000 h. In situ characterization reveals the structural evolution of the catalyst during water oxidation. In addition, the RME-PLS strategy enables tunable particle size control, highlighting its broad adaptability. This work establishes a general, scalable, and air-compatible platform for the rapid and phase-selective synthesis of transition metal compound nanoparticles.
Organic-inorganic composite solid-state electrolytes (CSSEs) represent a promising class of electrolyte materials for solid-state lithium batteries, as they effectively integrate the processability of polymers with the ionic transport, mechanical, and interfacial properties of inorganic solid-state electrolytes. However, their design usually does not rely on straight-forward filler-addition strategy, because each category of inorganic phases exhibits distinct conductivities, surface chemistries, structural connectivity, and processing compatibility. In this review, we discuss CSSEs based on specific functions and limitations of filler materials. For polymer-oxide systems, of the analysis focuses on local interfacial regulation, continuous ceramic pathways, and multilayer architectures tailored for electrode-specific interfaces. Polymer-sulfide systems are discussed with an emphasis on the preservation of intrinsic ionic conductivity during thin-film formation, which critically depends on binder chemistry, solvent compatibility, film density, and sulfide-sulfide contact. Polymer-halide systems are examined as an emerging direction for high-voltage cathode environments and interfacial stabilization, where growing opportunities emerge to extend their use toward thin, stable, and low-resistance electrolyte films. Finally, this review links filler-specific design with scalable, low-resistance thin films and practical cell integration, while identifying quantitative filler-polymer interfacial relationships, mechanical reliability, low-pressure operation, and dry-room processability as key future directions.
Electrostrain in lead-free relaxor piezoceramics is governed by the interplay between phase heterogeneity and defect-mediated polarization dynamics. Here, a BNT-SBT ceramic system is employed to elucidate how thermal post-processing modulates electromechanical behavior without compositional modification or external conditioning. The treatment induces a redistribution of rhombohedral (R3c) and tetragonal (P4bm) phase fractions, accompanied by reconfiguration of defect-related environments. Electron paramagnetic resonance reveals the presence of oxygen-vacancy−related defect states, while XPS analysis indicates a redistribution of near-surface oxygen chemical states. Despite the mixed-phase structure, polarization measurements exhibit diffuse relaxor characteristics, suggesting that long-range domain switching plays a limited role, whereas the reversible strain response is predominantly governed by electrostrictive polarization dynamics, facilitated by oxygen-vacancy–related defect states. A significant enhancement in electrostrictive response is confirmed by the increased electrostrictive coefficient (Q33) and the linear S–P2 relationship. Consequently, the maximum strain increases from 0.25% to 0.51%, with a normalized strain coefficient of 729 pm⋅V−1. The results indicate that the enhanced strain originates from an electrostriction-dominated response enabled by processing-induced defect-phase coupling and local structural heterogeneity. This work provides a processing-driven pathway for tuning electromechanical properties in BNT-based relaxor ceramics and offers insight into strain generation mechanisms beyond conventional domain-switching models.
The applications of magnesium aluminate spinel (MgAl2O4) ceramics often require optical transparency, suggesting minimal macroscopic flaws otherwise too strong light scattering would make them opaque. Yet the flexural strength typically in 200–350 MPa range is unsatisfactory, suggesting rather large critical flaw size for fracture in brittle materials. Such inconsistency makes MgAl2O4 an interesting system to study ceramic processing, strengthening, and toughening. Here, we reported progress in pressurelessly sintered zirconia toughened MgAl2O4 ceramics with 700 MPa flexural strength, surpassing those reported in the literature by hot pressing and other techniques. The new advance was achieved by colloidal processing and two-step sintering, for improved microstructural control, minimized microscopic defects, uniform two-phase distribution, and suppressed grain growth. We found ZrO2 acts as sintering aid for MgAl2O4, effectively lowering the sintering temperature by 150 °C. The optimized two-step sintering was conducted first at 1325 °C without holding reaching a critical relative density of 93%, and then at 1225 °C for 20 h for full densification. The low pressureless sintering temperature of 1225 °C plus the two-phase inter-pinning refine the grain size to 184 nm for MgAl2O4 and 155 nm for zirconia, offering microstructural benefits for strengthening. The zirconia grains stabilized by matrix constrain and partial Mg2+ alloying are mostly tetragonal and mechanically transformable, offering active toughening mechanism to reduce flaw sensitivity. The fracture is intra-granular for MgAl2O4 and mixed intra- and inter-granular for zirconia. Our work demonstrates the possibility to further strengthen MgAl2O4 ceramics towards 1 GPa for advanced and new applications.
To meet the sensing demands of extreme environments, such as those encountered in aircraft engines and nuclear industries, there is an urgent need to develop new piezoelectric crystals with excellent stability in piezoelectric performance. In this study, rare-earth mixed ErxGd1−xCa4O(BO3)3 (ErxGd1−xCOB, x = 0.30, 0.40, and 0.45) crystals were grown via the Czochralski method, and the electro-elastic properties were characterized over the temperature range of −100 °C to 900 °C. The results demonstrated that the Er0.45Gd0.55COB crystal exhibited exceptional temperature stability across the entire temperature range, with a negligible variation of only −3% in the piezoelectric coefficient d26. The fatigue behaviors of the electrical resistivity and piezoelectric coefficient were further investigated at 850 °C for 100 h. The results indicated that the electrical resistivity of Er0.45Gd0.55COB crystal remained within the same order of magnitude, approximately 8× 107 Ω⋅cm, whereas the piezoelectric coefficient d26 decreased only slightly by −4.2%. Furthermore, a prototype piezoelectric vibration sensor with an average sensitivity of 0.75 pC/g was fabricated using the Er0.45Gd0.55COB crystal, and the sensor exhibited a negligible sensitivity variation of ∼4% over the temperature range of 25–800 °C. These results demonstrate the strong potential of ErxGd1−xCOB crystals for high-temperature piezoelectric sensing applications.
High-entropy design has emerged as a powerful strategy to induce configurational disorder and relaxor behaviour in ferroelectrics; however, its effectiveness in crystallographically constrained systems remains unclear. Here, we address this gap by investigating the filled tungsten bronze ferroelectrics derived from Sr2KNb5O15 with multiple cations (Ca2+, Sr2+, Ba2+, Pb2+, K+ and Na+) introduced at A-sites. Single-phase high-entropy ceramics with tetragonal P4bm symmetry are successfully stabilised, exhibiting the increased Curie temperature and improved piezoelectric performance, if compared to the parent compound. Despite the high configurational entropy, the materials display diffuse ferroelectric phase transitions rather than relaxor behaviour. Structural and dielectric analyses reveal that intrinsic A1/A2 site-selective occupation persists, leading to partially ordered local structures and the coexistence of multiple polar states. Ferroelectric measurements further confirm the presence of dual polar states and field-induced transitions, while strain responses indicate the absence of non-180° domain contributions. The enhanced piezoelectric performance associated with high-entropy induced multi-polar configurations exhibits great potential in the applications of ultrasonic detetors. This work provides new insight into the interplay between entropy-driven disorder and site-selective ordering, offering guidance for the design of high-performance ferroelectric materials.
Achieving high critical current density in practical superconductors for high-field applications requires well-connected fine grains decorated with nano-scale crystalline defects to immobilize magnetic vortices. In compounds with rigid crystal lattices, however, grain refinement is usually accompanied by the release of stored strain energy rather than the retention of defects. Here, we demonstrate a scalable fluid-assisted milling strategy to produce high-purity Ba1–xKxFe2As2 precursor powders with uniform grains. Unlike dry milling that induces catastrophic fracture through breaking Fe–As covalent bonds, the liquid medium buffers impact energy and promotes shear-dominated deformation. This shear-dominated process selectively disrupts the weaker Ba–As ionic bonds, inducing a concerted lattice twist around the [001] axis and triggering the self-organization of interwoven screw dislocation networks. The dislocations with a density 2–4 orders of magnitude higher than those in conventional ceramics serve as strong pinning centers for magnetic vortices. Together with better grain connectivity and texture, the tapes fabricated from optimally milled powders exhibit a 50% enhancement in critical current density, reaching 1.45 × 105 A/cm2 at 4.2 K and 10 T. Our results establish fluid-assisted milling as a practical route to synergistically refine grains and construct strong pinning landscapes, offering a scalable pathway to high-performance iron-based superconductors.
Oxide and fluoride particles are widely employed to stabilize lithium metal anodes, yet the fundamental origin of their distinct interfacial behaviors remains unclear. Herein, we perform systematic density functional theory calculations to compare six representative interfaces: Li2O|Li, MgO|Li, Al2O3|Li (oxides) and LiF|Li, MgF2|Li, AlF3|Li (fluorides). The data show that interfacial adhesion, charge transfer, and work function are governed by anion charge and cation valence. The stronger interfacial hybridization enhances charge redistribution, generating larger interfacial dipoles that raise the work function. Molecular dynamics simulations reveal that these static characteristics evolve under thermal activation, with sustained Li migration into the coating, highlighting the necessity of finite-temperature assessment. These atomic-scale insights establish quantitative design principles for artificial solid electrolyte interphases.
Organic solvent additives are widely employed in aqueous zinc-ion batteries (AZIBs) to achieve high coulombic efficiency (CE), regulate oriented zinc deposition, and stabilize interfacial chemistry. However, conventional screening strategies rely primarily on bulk molecular electronic behavior, often overlooking the interfacial energetics that govern additive-electrode interactions. Herein, using density functional theory calculations, we introduce a dual-descriptor framework based on the molecular electrostatic potential minimum (ESPmin) and the molecule-electrode surface free energy (γ). This approach effectively incorporates solvent behavior and interfacial structural stability, establishing clear screening criteria for high-CE electrolytes. By analyzing 319 literature-reported organic solvents, including 29 additives with established experimental CE, we demonstrate that the high-CE region (> 99.5%) falls into a specific energetic window of ESPmin > –2.0 eV and γ < –0.015 eV·Å–2. Furthermore, molecular dynamics (MD) simulations reveal that candidates matching these criteria, such as the experimentally validated chloroacetamide (CTA) and 1,4-butanediol (BDO), reconfigure the Zn2+ primary solvation sheath to deplete active water at the electrode interface, thereby enabling highly reversible and uniform zinc plating. Ultimately, this work establishes a direct correlation between intrinsic molecular properties and interfacial characteristics, offering a screening methodology that can be readily extended to other advanced battery systems.
Bismuth silicate (Bi12SiO20, BSO) is a kind of multifunctional crystal material that has application prospects in the field of high-temperature sensing. In this study, the full set of electro-elastic constants of BSO crystal was characterized by the resonance method. A double-rotated cut (ZXtl45°/54°) with a central resonance frequency of 150 kHz and a high effective piezoelectric coefficient was designed. Temperature dependency of all independent electro-elastic constants was subsequently investigated. At room temperature, and were determined to be on the order of 45.7 pC/N and 28.4 pC/N, respectively. Based on this optimized crystal cut, a prototype of piezoelectric acoustic emission (AE) sensor was fabricated. Its performance was evaluated through Hsu-Nielsen tests to assess its reliability for structural health monitoring (SHM). The prototype exhibited a high and stable signal response from 25 °C to 500 °C with no missed detection. The peak-to-peak signal amplitudes were 207 mV at 25 °C and 199 mV at 500 °C. Notably, the signal-to-noise ratio (SNR) remained above 24 dB across the entire temperature range (25–500 °C). These results indicated the advantages of the BSO-based piezoelectric acoustic emission sensor for SHM applications at elevated temperatures.
All-solid-state batteries (ASSBs) require solid electrolytes with both high ionic conductivity and favorable mechanical properties to maintain intimate interfacial contact with electrode particles during cycling. Herein, we report a new silicon-based solid electrolyte, Li2SiI4O, designed through theoretical calculations and subsequently synthesized experimentally. For an ideal amorphous deep-eutectic Li2SiI4O system, theoretical calculations predict a Young's modulus below 5 GPa, suggesting excellent mechanical compliance and potential plasticity. Indeed, the experimentally synthesized Li2SiI4O exhibits a Young's modulus of 19.8 GPa, lower than that of typical sulfide solid electrolytes with Young's modulus of approximately 23 GPa. This relatively low modulus is expected to improve interfacial contact between the active electrode materials and the solid electrolyte, resembling the conformal contact commonly observed at solid–liquid interfaces. Electrochemical impedance spectroscopy measurements show that Li2SiI4O exhibits an ionic conductivity of 1.23 × 10−4 S/cm at room temperature. When employed as the solid electrolyte in ASSBs, the assembled cells deliver stable cycling performance with 80% capacity retention after 800 cycles. These results demonstrate that Li2SiI4O is a promising solid electrolyte candidate for practical ASSBs by combining favorable mechanical compliance with stable electrochemical performance.
Multicationic nitrides are emerging as a new class of high-performance electrode materials for micro-supercapacitors (MSCs), yet their synthesis and structural control remain challenging. Here, we report the fabrication of VWN nanolaminates using reactive magnetron sputtering deposition method. The deposition pressure and Ar/N2 ratio are systematically tuned to optimize morphology and electrochemical performance. The 100 nm resulting films, composed of alternating 2 nm-thick VN and W2N layers, achieve a high volumetric capacitance of 1400 F·cm−3 at 5 mV·s−1 in 1 mol/L KOH, among the best reported multicationic materials for MSCs. We demonstrate that preferred-oriented nanolaminate growth and interface stabilization occur when VN is used as the initial layer, with a critical VN layer thickness of ≤50 nm. Structural characterization via TEM and XRD reveals the formation of a cubic Fm3¯m phase, while electrochemical analyses confirm exceptional rate capability and cycling stability. Post-annealing treatments further elucidate the stabilization mechanism of the nanolaminate architecture. This work provides a rational design strategy for engineering multicationic nitrides with tailored electrochemical properties, offering a promising pathway for next-generation energy storage devices.
Ca1–xMgxY2Ge3O10 ceramics were synthesised using the solid-state reaction method. XRD analysis reveals that the solid solubility limit of Mg2+ in Ca1–xMgxY2Ge3O10 lies between x = 0.15 and 0.20. Multiple characterisation approaches, including Phillips–van Vechten–Levine theory and bond valence analysis, were employed to systematically elucidate the crystal structure and microwave dielectric properties. TEM analysis revealed a distinct superlattice structure in the material, characterised by an increased density of (001) planes along the [100] zone axis. The presence of superlattice in Ca0.9Mg0.1Y2Ge3O10 gives rise to a higher degree of lattice ordering, thereby reducing the intrinsic loss. The corrected dielectric constant shows a trend opposite to the αDT/Vm from Clausius–Mossotti (C–M) equation, primarily because of the rattling effect induced by Mg2+ substitution, which limits the applicability of the C–M equation. The intrinsic loss of CaY2Ge3O10 was assessed by far-infrared spectroscopy. Key factors governing the microwave dielectric properties include total lattice energy (Ut), ion activation energy (Ea), and packing fraction (P.F.), which collectively determine the variation in Q×f, whereas the average distortion of Y–O bonds (Ave(δY–O)), the rattling effect and proportion of Ge–O bonds in total polarizability (χ(Ge–O)/χ), primarily affect τf. The Ca0.9Mg0.1Y2Ge3O10 ceramic exhibits an enhanced Q×f, with microwave dielectric properties of εr = 10.1, Q×f = 106,440 GHz, and τf = −27.1 × 10−6 °C−1. At x = 0.15, a reduced Ave(δY–O), a maximum χ(Ge–O)/χ, and a stronger rattling effect are observed, leading to a near-zero τf of −9.7 × 10−6 °C−1, with εr = 10.3 and Q×f = 91,920 GHz.
P2-type sodium-deficient Mn-based layered oxides with anionic oxygen redox are promising cathodes for high-energy sodium-ion batteries, yet their practical application is hindered by irreversible oxygen loss, transition-metal migration, parasitic interfacial reactions, and rapid structural degradation under high-voltage operation. Herein, we propose a phytic acid (PA)-mediated multiscale reconstruction strategy to regulate the surface to near-bulk structure of P2-type Na0.72Li0.24Mn0.76O2 (NLM). Upon secondary annealing, PA transforms the residual surface alkali into an ion-conductive Na3PO4 outer layer. Meanwhile, the annealing-induced localized reductive environment promotes oxygen-vacancy (VO) formation and gradient P5+ doping in the near-bulk region. The P5+ preferentially coordinates as [PO4] tetrahedra to replace [MO6] octahedra, enlarging the charge-transfer gap (Δ) via the inductive effect. Concurrently, the charge compensation effect drives local Mn4+ reduction, which lowers the Hubbard U. This dual band regulation thermodynamically stabilizes the lattice oxygen. Furthermore, the VO-enriched environment and P5+ doping synergistically drive the migration and subsequent oxidation of the reduced Mn species, triggering the formation of a Li2MnO3-like buffer interphase. Consequently, the modified PA-NLM delivers an improved rate capability of 99.19 mAh·g-1 at 5 C and enhanced long-term cycling stability, retaining 124.3 mA·h·g–1 within 1.8–4.7 V after 150 cycles at 1 C. This work provides a viable surface-to-near-bulk stabilization paradigm for durable high-voltage sodium-ion cathodes.
Even though there have been significant advancements in the development of rare earth (RE) doped upconversion (UC) materials, the challenge remains to develop highly efficient UC phosphors due to scientific interest and application need. Here, we report that heterojunction engineering leads to the significant UC emission enhancement of Er3+ ions, challenging the long-standing notion that luminescence of RE ions is nearly independent of photocarrier transfer. It shows that via an in-situ construction strategy, Bi2O3 is placed on Bi3O4Br:Er3+ nanosheets to compose type II heterojunction, allowing photogenerated holes to transfer from matrix semiconductor to the Bi2O3. Thus, under excitation by 1550 nm laser, the outer heterojunction prolongs the decay time of Er3+ and improves the integral intensity of visible UC emission nearly 25.0 times. The results of experiment and theory calculation indicate that under near-infrared light irradiation, photogenerated-hole transferring via heterojunction suppresses the recombination of excited electrons occupying intermediate energy states in Er3+, enabling energy reabsorption processes that trigger subsequent transitions to higher-lying levels. This finding of the work provides an insight into the influence of carrier migration on the photoluminescence of lanthanide ions, which will be helpful for the development of optoelectronic devices related to RE ions.
Limiting oxygen ingress through surface-connected defects is critical for improving the oxidation durability of carbon-fiber-reinforced ceramic-matrix composites at high temperatures. Conventional strategies based on external coatings or passive oxide scales may be compromised during thermal cycling because thermal mismatch, cracking, and spallation can reopen pathways for oxygen ingress. This study reveals a coating-independent and intrinsically adaptive oxidation-protection mechanism in Y2Si2O7-based composites, primarily enabled by a sol-gel derived intergranular amorphous SiO2 nanophase that assists in situ defect sealing during high-temperature oxidation. At 1400 °C, the amorphous grain-boundary SiO2 undergoes viscous relaxation and local redistribution, which helps seal surface-connected pores and microcracks, reduces open-defect connectivity, and confines oxidation mainly to the subsurface region. During thermal cycling, the surface further evolves into a bilayer structure with a compliant porous outer zone and a relatively dense inner layer, helping relieve thermal strain while suppressing deep oxygen permeation. After oxidation at 1400 °C for 2 h and thermal-shock, the composite retained 99.69% and 98.42% of its initial mass, respectively. Unlike conventional protection strategies that rely on external coatings or passively formed oxide scales, the present composite exploits temperature-responsive intergranular amorphous SiO2 to assist the in situ closure of surface-connected defects, thereby limiting oxygen ingress during high-temperature exposure. This work demonstrates a coating-free adaptive design strategy for improving the durability of carbon-fiber-reinforced ceramic-matrix composites in high-temperature.
Prussian blue analogue (PBA) derivatives have been widely regarded as next-generation electromagnetic (EM) wave absorbers, attributed to their tailorable architectures and compositions. However, conventional pyrolysis of PBA often causes agglomeration of metal nanoparticles and the destruction of polarization interfaces, thereby limiting EM dissipation capacity. To address this, we propose an ultrafast thermal shock strategy to synthesize nanoscale CoFe alloy anchored on a porous carbon matrix, utilizing CoFe-PBA as the precursor. The transient thermal shock process suppresses grain overgrowth while preserving structural defects, thereby generating abundant interfacial polarization sites and optimizing electrical conductivity. The resulting CoFe/C composite features rich interfacial structures and efficient charge transport pathways. Consequently, it delivers exceptional EM wave absorption performance with a minimum reflection loss of −43.24 dB at a thickness of 1.9 mm, alongside a broad effective absorption bandwidth of 5.57 GHz at 2.2 mm. Comprehensive electromagnetic analysis reveals that the superior performance originates from a synergistic mechanism involving a magnetic coupling network, enhanced interfacial and dipole polarizations, tailored conduction loss, and optimal impedance matching. This work not only presents a highly efficient EM wave absorber but also paves an efficient pathway for the rational design of advanced multi-component functional composites.
Solution-processed oxide semiconductors are promising for low-cost, large-area flexible electronics. However, conventional multi-step deposition and prolonged thermal annealing reduce throughput. In addition, the uncontrolled accumulation of precursors leads to nonuniform thickness, hindering ultrathin channel formation. Unlike traditional methods, spray pyrolysis not only enables post-annealing-free in situ growth but also inherently limits precursor supply through droplet-by-droplet delivery, enabling quasi-ALD-like self-limited growth for precise thickness control. Here, we demonstrate post-annealing-free ultrathin InGaO channels via spray pyrolysis at 300 °C. X-ray photoelectron spectroscopy and transmission electron microscopy confirm a chemically homogeneous ∼5 nm InGaO layer free of organic residues. The resulting thin-film transistors exhibit hysteresis-free operation, a high mobility of (54.98 ± 3.32) cm2⸱V–1⸱s–1, an ION/IOFF ratio exceeding 108, and a subthreshold swing of 126 mV/dec, along with excellent bias-stress stability at low gate voltages (<5 V). Therefore, Spray pyrolysis enables the scalable fabrication of ultrathin oxide channels for flexible electronics.
