SCIENCE CHINA Materials•2026•DOI: 10.1007/s40843-025-3520-1
Solution-processed metal halide perovskite light-emitting diodes (PeLEDs) have advanced rapidly due to high color purity, tunable emission, and low cost, with external quantum efficiencies (EQEs) surpassing 30%. However, high EQEs are typically achieved at low brightness, suffering severe efficiency roll-off at high current densities due to Auger recombination and Joule heating. Three-dimensional (3D) perovskites offer superior charge transport but suffer from low photoluminescent quantum yield (PLQY) and efficiency roll-off. The fundamental roll-off mechanism remains poorly understood. Recently, Yao and co-workers developed a molecule-in-lattice-enabled intragrain heterostructure in 3D perovskite to promote carrier confinement. Using device-level ultrafast spectroscopy, they identified hole leakage as the origin of efficiency roll-off in pure-red CsPbI3−xBrx PeLEDs. A strong bonding small molecule with multiple anchor groups was introduced to penetrate the lead halide octahedron framework, constructing wide bandgap barriers inside perovskite grains, reducing hole leakage without compromising carrier transport. This approach enabled ultrabright, highly efficient, and stable pure-red PeLEDs with extremely low efficiency roll-off. The work provides a new strategy for achieving high brightness and efficiency simultaneously, advancing PeLED technology toward practical applications in displays and lighting.
Journal of Environmental Engineering Technology•2026•DOI: 10.13205/j.hjgc.202608012
The challenge of limited phosphorus removal efficiency in low-carbon municipal wastewater is addressed by the innovative side-stream enhanced biological phosphorus removal (S2EBPR) process, which has garnered significant attention. Recent research highlights the core mechanism rooted in the metabolic traits of phosphorus accumulating organisms (PAOs), pivotal for effective phosphorus removal. However, conventional enhanced biological phosphorus removal (EBPR) processes face constraints under low C/P conditions, where the scarcity of carbon source weakens PAOs’ competitive edge, directly impeding phosphorus removal efficiency. Consequently, S2EBPR establishes a side-stream sludge fermentation unit, through which anaerobic fermentation conditions are precisely regulated and PAOs’ dominant position in carbon source competition is strengthened, thereby enhancing the enrichment of PAOs and the optimization of their metabolism. This breakthrough not only overcomes the low C/P limitation but also underscores the fundamental advantage of S2EBPR. Furthermore, the discussion delves into the critical operational and environmental parameters influencing its efficacy, offering a foundation for precise process management. Looking ahead, the synergistic development of S2EBPR alongside emerging water treatment technologies holds promise for simultaneously efficient nitrogen and phosphorus removal in wastewater treatment, thereby furnishing technical insights for fostering sustainable resource recycling practices.
SCIENCE CHINA Materials•2026•DOI: 10.1007/s40843-025-3987-x
A hierarchically porous nickel salicylate (Ni-SA) metal-organic framework (MOF) was constructed via a salicylate coordination strategy to precisely modulate the microenvironment of nickel active sites for efficient electrocatalytic glucose oxidation. The ortho-hydroxy-carboxylate chelation directs atomic-level organization of Ni2+ sites within nanobelt assemblies, maximizing active site accessibility. Robust Ni–O coordination stabilizes Ni3+ intermediates during C–H bond cleavage, leading to remarkable catalytic stability. The optimized Ni-SA-2 catalyst achieved a high sensitivity of 5.97 mA mM−1 cm−2 and a low detection limit of 0.71 μM (S/N = 3), with 85.4% current retention after 8 h continuous operation. This design paradigm demonstrates universal applicability, as evidenced by successful extension to isostructural M-SA analogs (M = Co, Fe, Cr, Mn) under identical synthetic conditions, establishing metal-salicylate frameworks as a versatile electrocatalyst platform.
SCIENCE CHINA Materials•2026•DOI: 10.1007/s40843-025-4082-6
High-performance nonvolatile memory devices are crucial for next-generation computing, yet achieving low-power, stable, and reproducible resistive switching remains challenging, primarily due to stochastic filament formation and limited precise control over the electronic properties of active materials. Herein, we employ a rational molecular engineering strategy to address these limitations by constructing a series of two-dimensional pyrene-based covalent organic frameworks (Py-COFs)—Py-H, Py-CH3, and Py-OH—via systematic substitution (–H, –CH3, and –OH) on the phenyl linkers to modulate backbone electronics. The electron-donating –CH3 and –OH motifs enrich the π-conjugated backbone with higher electron density, while the –OH moiety in Py-OH further engages in p-π conjugation with the benzene ring and forms intramolecular hydrogen bonds, thereby increasing framework rigidity, enhancing orbital overlap, and promoting charge delocalization. Enabled by these structural refinements, Py-OH-based devices exhibit markedly improved resistive switching behavior, characterized by a low operating voltage, an ON/OFF ratio of ~10^3.45, and excellent retention stability. Combined photophysical, electrochemical, and high-resolution TEM analyses corroborate that hydroxyl-driven p-π conjugation, hydrogen-bond reinforcement, and the emergent nanowire-like morphology synergistically suppress uncontrolled filament formation and promote efficient charge transport. These findings establish a clear structure-property correlation in functionalized Py-COFs and underscore their promise as tunable active layers for low-power, high-performance resistive memory and neuromorphic computing.
SCIENCE CHINA Materials•2025•DOI: 10.1007/s40843-025-3453-y
Organic semiconductor single-crystal (OSSC) arrays are pivotal for high-performance integrated electronics, yet the fundamental principles governing molecular design for one-dimensional (1D) crystalline nanostructures and the role of intermolecular interactions in solution self-assembly remain unresolved. This study introduces a molecular engineering strategy employing hetero-buckybowl trichalcogenasumanenes to direct the self-assembly of OSSC arrays. The distinctive concave-convex architecture promotes 1D crystal formation via directional π-π interactions while suppressing intercolumnar coupling, thereby enhancing structural anisotropy and charge transport. Centimeter-sized OSSC arrays were fabricated on various substrates through solution self-assembly. Organic field-effect transistors (OFETs) based on these arrays exhibited hole mobility up to 0.89 cm² V⁻¹ s⁻¹ (average 0.65 cm² V⁻¹ s⁻¹), with minimal device-to-device variation, surpassing previous buckybowl-based devices. The six butoxy groups in molecule 4 improve solubility and stabilize molecular morphology against strain, yielding flexible OFETs with outstanding bendable durability. This strategy significantly enhances crystallinity and uniformity, offering a pathway for high-performance, large-area organic electronics.
SCIENCE CHINA Materials•2025•DOI: 10.1007/s40843-025-3529-7
Thermoelectric cooling offers a fluoride-free alternative to vapor compression refrigeration, yet commercial adoption is constrained by low figures of merit (ZT) and high material costs. This study reports an economical fabrication route for conductive polyethylene/polypyrrole@constantan (PE/[email protected]) composites via a self-created extensional rheological technology. Pyrrole monomers are polymerized on Ni0.49Cu0.59 particles and subsequently dispersed within a polyethylene matrix under an extensional flow field, forming a continuous conductive network. The resulting composite exhibits an electrical conductivity of 1699.8 S cm−2, a thermal conductivity of 13.9 W m−1 K−1, and a ZT of 0.16 at 25 °C. A thermoelectric device integrating PE/Ppy@iron achieved a temperature reduction of 0.4 °C under 30 V/0.3 A direct current. Square-wave pulsed current excitation stabilized the cooling efficiency at its optimum level, while a custom thermal insulation system mitigated parasitic heat loss, collectively yielding a total temperature reduction of 1.6 °C. These results demonstrate a scalable, low-cost pathway for thermoelectric cooling materials, with potential for large-scale commercialization.