SCIENCE CHINA Materials•2026•DOI: 10.1007/s40843-026-4499-9
Two-dimensional (2D) ferroelectric materials have emerged as promising candidates for next-generation non-volatile memory and neuromorphic computing, yet their integration into commercial devices faces substantial hurdles. This review critically examines the structure, properties, and applications of ferroelectric 2D In-Se materials, with a focus on their potential to overcome the scaling and retention limitations of conventional ferroelectrics such as Hf0.5Zr0.5O2 (HZO). The manuscript synthesizes recent advances in In-Se ferroelectricity, including the mechanisms of polarization switching, modulation strategies, and device demonstrations. Key experimental benchmarks from the literature are analyzed, such as the high data retention and read endurance of 5-nm HZO ferroelectric FETs (IEEE Electron Device Lett, 2019, 40(3): 399-402) and the giant barrier height modulation in ferroelectric van der Waals heterojunctions (Nat Electron, 2020, 3: 466-472). The review also highlights the performance of sliding ferroelectric memories based on rhombohedral-stacked bilayer MoS2, which achieved non-volatile storage with low power consumption (Nat Commun, 2024, 15: 10796). Despite these advances, critical challenges remain: the scalability of In-Se synthesis, the control of domain dynamics at the nanoscale, and the cost parity with silicon-based technologies. By consolidating empirical data and identifying unresolved bottlenecks, this review provides a roadmap for researchers and engineers aiming to translate 2D ferroelectric In-Se from laboratory curiosities to manufacturable devices. The analysis underscores the need for standardized metrology and accelerated lifetime testing to validate industrial viability.
SCIENCE CHINA Materials•2026•DOI: 10.1007/s40843-025-3625-3
Zirconia (ZrO2)-based fluorite ferroelectric materials are promising for nonvolatile memory and logic devices due to their CMOS compatibility and cost advantages over hafnium oxide (HfO2). However, the metastable nature of the ferroelectric orthorhombic phase (o-phase) hinders practical application. Here, we report the strain-mediated stabilization of the ferroelectric o-phase in ZrO2 thin films grown on niobium-doped strontium titanate (NSTO) substrates with different crystallographic orientations via chemical solution deposition. Systematic structural and ferroelectric characterization, combined with simulation, reveals that substrate orientation controls in-plane tensile strain, selectively promoting epitaxial growth of the o-phase. The ZrO2 film on NSTO(110) exhibits the highest o-phase content, achieving a remanent polarization (2Pr) of 92.64 μC/cm², which remains as high as 88.54 μC/cm² after resistive-capacitive (RC) delay calibration. The device shows endurance of approximately 10^7 cycles with favorable fatigue characteristics. X-ray absorption spectroscopy (XAS) further indicates distortion of Zr-O tetrahedra, providing microscopic insight into the ferroelectricity. This work presents a novel strategy for property tuning of ZrO2 films and supports their application in storage and logic devices.
SCIENCE CHINA Materials•2026•DOI: 10.1007/s40843-025-3710-y
Layered transition metal oxide cathodes for sodium-ion batteries (SIBs) suffer from Jahn–Teller distortion of MnO6, Na+/vacancy ordering, and irreversible lattice oxygen loss, causing capacity fading and voltage decay. Here, we report a P2-type material, Na0.67Ni0.3Mn0.6Li0.09Sn0.01O2 (NNMO-Li0.09Sn0.01), co-doped with closed-shell Li+ and Sn4+ ions. Li+ increases the Mn4+/Mn3+ ratio, mitigating Jahn–Teller distortion, and disrupts Ni/Mn ordering, suppressing Na+/vacancy ordering. Sn4+ forms stronger Sn–O bonds (548 kJ mol−1), enhancing bonding between transition metal ions and oxygen, reducing oxygen loss. NNMO-Li0.09Sn0.01 delivers a specific capacity of 90.3 mAh g−1 with 62.9% capacity retention after 50 cycles at 0.1 C (1 C = 200 mA g−1), and 90.3% voltage retention. This closed-shell substitution strategy offers a viable approach for enhancing structural stability of wide-voltage layered oxide cathodes.
Journal of Environmental Engineering Technology•2026•DOI: 10.13205/j.hjgc.202604026
Polycyclic aromatic hydrocarbons (PAHs) are persistent organic pollutants ubiquitously present in soils, posing severe risks to ecosystems and human health. This study synthesized MIL-88A(Fe) via a hydrothermal solvent method and applied it to the photocatalytic degradation of phenanthrene-pyrene (PHE-PYR) composite contaminants in soil, investigating the adsorption-photocatalytic synergy. Results demonstrated that adsorption of PHE-PYR onto MIL-88A(Fe) was dominated by physical and monolayer surface adsorption, with a maximum adsorption capacity of 97.25 mg/kg. This strong adsorption increased pollutant concentration near active sites, accelerating photocatalytic degradation. Under optimal conditions—3% catalyst dosage, 40% soil water content, 60 min visible light irradiation, initial pollutant concentration of 200 mg/kg, and acidic soil—the total degradation efficiency reached 79.20%. Photoelectrochemical characterization revealed significant visible-light response (200–600 nm), a narrow bandgap of 3.04 eV, and favorable band structure facilitating efficient electron-hole separation. Quenching experiments identified superoxide radicals (·O2−) and holes (h+) as primary reactive species. GC-MS analysis of intermediates indicated that PYR undergoes hydroxylation, oxidation, and ring-opening to form PHE, which is further hydroxylated and oxidized, ultimately mineralizing to CO2 and H2O. This work provides an efficient strategy for remediating PAH-contaminated soils.
Journal of Fuel Chemistry and Technology•2026•DOI: 10.1016/S1872-5813(26)60647-0
Photoelectrochemical (PEC) water splitting offers a direct route to convert solar energy into clean hydrogen fuel. CuBi2O4, a p-type semiconductor with a bandgap of 1.5–1.8 eV, exhibits visible-light responsiveness and good stability, yet its performance is limited by high interfacial resistance and severe charge carrier recombination. This study introduces a CuO interlayer between fluorine-doped tin oxide (FTO) and CuBi2O4 to construct CuO/CuBi2O4 photocathodes, aiming to improve interfacial charge transfer. The optimized CuO/CuBi2O4-200 photocathode achieved a photocurrent density of −1.71 mA/cm² at 0 V vs. RHE, more than 3.5 times that of bare CuBi2O4. Incident photon-to-current efficiency (IPCE) at 365 nm reached ~13%, and the maximum applied bias photon-to-current efficiency (ABPE) was 0.17%. Water splitting experiments yielded 2.05 μmol/cm² of hydrogen, significantly surpassing the unmodified photoelectrode. Mechanistic studies indicate that the CuO layer establishes favorable band alignment, promotes hole transport toward the FTO substrate, and suppresses interfacial carrier recombination. This work demonstrates a simple and efficient interfacial engineering strategy, offering insights for the design of high-performance semiconductor-based PEC photoelectrodes.
Environmental Chemistry•2026•DOI: 10.0000/202605-1
A method for the determination of hydrazoic acid and sodium azide in workplace air was established using ion chromatography with suppressed conductivity detection. Vapor and mist states of hydrazoic acid were collected in 40 mg·L−1 KOH absorption solution, while sol states of hydrazoic acid or sodium azide were collected on microporous membranes and eluted with 40 mg·L−1 KOH. Separation was performed on a Dionex IonPac™ AS11-HC (250 mm × 4.0 mm) anion analytical column with KOH gradient elution, followed by suppressed conductivity detection. The azide ion (N3−) exhibited good linearity in the range of 0.005–0.5 mg·L−1, with a correlation coefficient (r) of 0.9997. The limit of detection (S/N=3) was 0.002 mg·L−1, and the limit of quantification (S/N=10) was 0.005 mg·L−1. The minimum quantifiable concentrations in air were 0.00256 mg·m−3 for hydrazoic acid and 0.00387 mg·m−3 for sodium azide, based on a 10.0 mL sample solution and a 20 L air sample. Spiked recoveries ranged from 92.0% to 100.4%, with relative standard deviations (RSD, n=6) between 0.76% and 2.51%. The method is efficient, accurate, and sensitive, suitable for monitoring and safety assessment of hydrazoic acid and sodium azide in workplace air.
SCIENCE CHINA Materials•2026•DOI: 10.1007/s40843-025-3862-x
Hexagonal boron nitride (hBN) is indispensable for next-generation electronics and quantum technologies, yet controlled synthesis of isotopically engineered hBN with macroscopic scalability and atomic-level precision remains challenging. Here, we present a plasma-enhanced chemical vapor deposition (PECVD) method using elemental boron (B) and nitrogen (N) precursors to achieve wafer-scale growth and precise isotopic control of hBN films. High-quality hBN films are synthesized on Cu substrates via optimized B evaporation and N2 plasma activation. The growth mechanism involves an oxygen-mediated pathway for B transport and a layer-by-layer (Frank-van der Merwe) mode for multilayer formation. By employing isotopically enriched B powders (10B and 11B) and N2 gases (14N2 and 15N2), we demonstrate tunable isotopic compositions with phonon mode shifts quantitatively matching harmonic oscillator predictions. Furthermore, we realize unprecedented in-plane h10BN-h11BN heterostructures through dynamic B source switching during growth. This PECVD strategy establishes a transformative synthesis platform merging industrial-scale production capacity with atomic-scale isotopic precision, enabling new opportunities to engineer thermal transport, optical response, and quantum coherence in two-dimensional materials.
Journal of Environmental Engineering Technology•2026•DOI: 10.13205/j.hjgc.202607011
Anaerobic digestion (AD) is a viable route for energy recovery from food waste (FW), yet it often suffers from process instability due to volatile fatty acids (VFAs) accumulation and subsequent pH drop. This study modified red mud (RM) with hydrochloric acid to produce acid-modified red mud (AMRM), aiming to optimize its alkalinity and physicochemical properties. The efficacy of AMRM as an additive in FW anaerobic digestion was systematically evaluated. Results demonstrated that adding 3% AMRM significantly enhanced the buffering capacity and controlled VFAs accumulation, particularly propionic acid. This was attributed to the developed pore structure of AMRM, whose specific surface area increased by 347% compared to raw RM, facilitating rapid VFAs adsorption. Furthermore, AMRM enriched hematite (Fe2O3), which elevated electron transport system (ETS) activity and coenzyme F420 content, suggesting its role as an electron carrier promoting direct interspecies electron transfer (DIET) between syntrophic bacteria and methanogens. Consequently, the cumulative methane yield reached 633.9 mL/g VS, which was 175.1% and 55.2% higher than the control and raw RM groups, respectively. The VS removal efficiency was 75.1%. This study provides a dual-pathway mechanism—adsorption and electron transfer—for enhancing AD performance, offering a cost-effective and sustainable strategy for FW treatment and RM valorization.
SCIENCE CHINA Materials•2026•DOI: 10.1007/s40843-026-4126-0
Flexible X-ray detectors are constrained by the difficulty of producing semiconductor films that simultaneously exhibit uniform morphology, high crystallinity, and mechanical robustness. Here, we introduce a hydrogen-bond engineered supramolecular (HBES) strategy to overcome these limitations in supramolecular bismuth halide clusters (PDBiI5). By incorporating polyacrylic acid (PAA), a dynamic supramolecular network is formed that suppresses the coffee-ring effect during ultrasonic spray-coating via increased solution viscosity and controlled kinetic balance between solvent evaporation and solute diffusion. The HBES approach also modulates crystallization kinetics, extending crystal growth time from 23 to 41 s, yielding densely packed films with enhanced crystallinity and reduced defect states. These improvements lead to superior charge transport: a hole mobility of 2.16 cm2 V−1 s−1 and a mobility-lifetime product of 9.1 × 10−4 cm2 V−1. The resulting X-ray detectors achieve a record sensitivity of 19,009 μC Gyair−1 cm−2 and an ultralow detection limit of 3.35 nGyair s−1, with excellent operational and environmental stability. Leveraging the mechanical robustness from the supramolecular network, we demonstrate the first direct-type flexible X-ray imager, retaining 85% performance after 1000 bending cycles. This imager overcomes geometric distortion and vignetting, maintaining 85% edge photocurrent versus 58% for rigid detectors, enabling clear imaging of curved objects. This work establishes a versatile supramolecular engineering paradigm for high-performance flexible X-ray detection and imaging.
SCIENCE CHINA Materials•2026•DOI: 10.1007/s40843-025-4173-x
Ferroelectric memory, with its promise of low power consumption, high writing speed and exceptional endurance, requires the scaling of ferroelectric films to ultrathin dimensions—often just a few atomic layers thick. However, such extreme thinning risks destabilizing or even erasing electric polarization, mainly due to the detrimental depolarization field. Remarkably, certain ferroelectrics exhibit an intrinsic immunity to this effect, as predicted theoretically and confirmed experimentally. Examples include improper ferroelectrics, hyper ferroelectrics, engineered heterostructures, and low-dimensional van der Waals ferroelectrics. This review systematically examines these unique materials, unravelling the fundamental physics behind their polarization robustness and the mechanisms enabling them to resist the depolarization field. By bridging theory with experimental advances, we aim to inspire the design of next-generation ferroelectrics capable of overcoming critical challenges encountered in practical ferroelectric memory devices.