SCIENCE CHINA Materials•2026•DOI: 10.1007/s40843-026-4343-7
Piezoelectric materials interconvert mechanical and electrical energy, but piezoceramics are brittle while PVDF-based ferroelectric polymers exhibit low piezoelectric coefficients (d33 ≈ -30 pC N-1). Chemical modification via morphotropic phase boundary (MPB) engineering has raised d33 in P(VDF-TrFE) to -63.5 pC N-1, and to -69 pC N-1 with stretching, but intrinsic piezoelectricity in relaxor terpolymers remains limited. Here, relaxor ferroelectric P(VDF-TrFE-CFE) with varying C=C double bond (DB) content is synthesized via dehydrochlorination. Structural and electrical characterization reveals that increasing DB content stabilizes long-range ferroelectric order while suppressing short-range relaxor characteristics, forming a trans/helix phase boundary. At a critical DB content of 2.0 mol%, a markedly enhanced intrinsic d33 of -129.0 pC N-1 is achieved, outperforming previous MPB approaches. This finding addresses the fundamental bottleneck of low piezoelectric response in flexible ferroelectric polymers and provides a viable route for high-performance wearable electromechanical devices.
SCIENCE CHINA Materials•2026•DOI: 10.1007/s40843-026-4480-1
Ternary organic solar cells (OSCs) incorporating a structurally compatible guest acceptor (C7-Cl) into the PM6:BTP-eC9 host system are demonstrated. The low Flory-Huggins interaction parameter between host and guest acceptors facilitates intimate mixing, optimizing molecular packing and energy-level alignment. High-sensitivity sEQE and EQEEL analyses reveal a reduced non-radiative energy loss (KE3) of 0.216 eV in the ternary device. Consequently, the optimized ternary OSC achieves a champion power conversion efficiency (PCE) of 20.02% and an improved T80 operational lifetime of 1065 h. This work establishes a feasible strategy via structurally compatible guest doping to simultaneously optimize vertical phase separation and suppress non-radiative loss, providing a facile and effective route toward high-performance and stable OSCs.
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.
Chinese Journal of Environmental Engineering•2026•DOI: 10.12030/j.cjee.202507111
This study investigated the effects of a ring-shaped pulsed electric field (PEF) (1.5 V, 4 h on-time per cycle) on nitrogen removal performance and microbial community structure of anammox granular sludge (AnGS). Two anaerobic sequencing batch reactors (R1 control, R2 with PEF) were operated under stepwise increasing nitrogen loading rates (NLR). At NLR below 1,155 mg·(L·d)−1, R2 exhibited total nitrogen removal efficiency (TRE) 7.5%–17.0% higher than R1, with biomass, specific anammox activity (SAA), and extracellular polymeric substances (EPS) increased by 5%–7%, 21%–71%, and 54%–77%, respectively. However, at NLR above 1,320 mg·(L·d)−1, the toxic effect of nitrite dominated, and PEF enhancement diminished or even reversed to inhibition. Microbial community analysis revealed that at low-to-moderate NLR, PEF increased the relative abundance of Planctomycetes and key anammox bacteria (Candidatus Brocadia and Candidatus Jettenia), along with enhanced community richness (Chao1) and diversity (Shannon/Simpson indices). At high NLR, PEF decreased microbial richness compared to R1. Principal component analysis and redundancy analysis indicated that PEF was the key factor driving community differences at low-to-moderate NLR, whereas nitrite concentration became the dominant factor at high NLR. This study provides theoretical support for enhancing the resilience and engineering application of anammox processes.
Chinese Journal of Environmental Engineering•2026•DOI: 10.12030/j.cjee.202509004
Acetone, a widely used solvent in the pharmaceutical industry, poses environmental and economic challenges due to its high volatility and the low concentration of acetone in water-based absorbents, which complicates recovery. This study proposes a composite absorbent comprising 1,4-butanediol (BDO), triethylene glycol, sodium citrate, and water, aiming to enhance acetone absorption capacity and enable cost-effective resource recovery. Response surface methodology optimized the absorbent composition to BDO 35%, triethylene glycol 10%, and sodium citrate 5%, achieving an acetone absorption capacity of 51.97 g·kg−1, which is 2.39 times that of pure water (21.77 g·kg−1). Density functional theory (DFT) calculations and AIM topological analysis revealed that BDO forms stronger hydrogen bonds with acetone, characterized by shorter bond lengths and higher electron density, underpinning its superior molecular recognition and absorption capability. Process simulation of absorption-regeneration cycles demonstrated that, compared to pure water, the composite absorbent reduces absorbent consumption by 36.2% and regeneration energy consumption by 41.15% while achieving effluent acetone concentrations below 100 mg·m−3. This multi-scale investigation, spanning macroscopic experiments, molecular mechanisms, and process simulation, validates the feasibility and advantages of BDO-based composite absorbents for VOC control, providing theoretical and data support for the engineering application of alcohol-based absorbents in efficient organic pollutant separation.
SCIENCE CHINA Materials•2026•DOI: 10.1007/s40843-026-4118-0
Polymer composite dielectrics are key materials for high-temperature film capacitors, yet their energy storage capability is severely constrained at elevated temperatures. Molecular fillers that simultaneously integrate deep-level trapping (high electron affinity, Ea), strong insulation (large bandgap, Eg), and high thermal stability are rarely available, posing a major challenge for improving high-temperature energy storage performance. To address this challenge, we screen and identify hexaazatriphenylene hexacarbonitrile (HAT-CN) as a promising candidate that fulfills the above critical requirements from numerous commercial organic molecules. When incorporated into a high glass transition temperature (Tg) polymer fluorene polyester (FPE), the resulting all-organic composite exhibits simultaneously suppressed high-temperature conduction loss and preserved mechanical robustness. Consequently, the optimized composite achieves record-high discharged energy densities of 7.31 J cm−3 at 150 °C and 6.14 J cm−3 at 200 °C (η≥90%) with a low cost and scalable process. This work demonstrates that the filler design based on synergistic key properties provides a potent pathway to break the longstanding high-temperature performance bottleneck in polymer dielectrics.
SCIENCE CHINA Materials•2025•DOI: 10.1007/s40843-024-3292-8
Ultrathick electrodes are pivotal for high mass loading and energy density, particularly in cold climates. Conventional electrode fabrication using slurry coating suffers from critical cracking thickness limitations and sluggish ion transport, while 3D printing demands rheologically suitable inks. Existing additives—polymer binders, conductive agents—compromise active content and electrochemical performance. This work introduces Ti3C2Tx MXene as a three-in-one additive functioning simultaneously as viscosifier, conductive agent, and active material. Highly concentrated MXene gel exhibits shear-thinning behavior enabling 3D printing of electrodes up to 1 mm thick. The multi-scale porous architecture facilitates rapid ion transport. A 3D-printed MoS3/MXene electrode achieves mass loading up to 18.4 mg cm−2 and areal capacity of 7.2 mA h cm−2, retaining 4.2 mA h cm−2 at −20 °C. A full cell with MoS3/MXene anode and Na3V2(PO4)3/MXene cathode delivers 400 Wh kg−1 energy density. This multifunctional MXene strategy addresses the trade-off between active content, printability, and low-temperature performance, offering a viable route for high-energy-density sodium-ion batteries in cold environments.