SCIENCE CHINA Materials•2026•DOI: 10.1007/s40843-026-4502-1
Near-infrared-II (NIR-II, 1000-1700 nm) luminescent materials are pivotal for deep-tissue bioimaging and optical communication, yet their performance is often limited by low quantum yields and thermal quenching. Here, we report a thermal-enhanced NIR-II luminescence in Sb3+/Er3+ co-doped Cs3GdCl6 microcrystals synthesized via a modified Bridgman method. Under ultraviolet excitation, the co-doped microcrystals exhibit intense NIR-II emission centered at 1532 nm corresponding to Er3+: 4I13/2 → 4I15/2 transition, with a maximum relative sensitivity of 1.2% K−1 at 303 K. Notably, the integrated NIR-II emission intensity increases by 2.3-fold from 298 K to 373 K, demonstrating anomalous thermal enhancement. This behavior is attributed to the thermally activated energy transfer from Sb3+ sensitizers to Er3+ activators, as confirmed by temperature-dependent photoluminescence spectra and decay kinetics. The energy transfer efficiency reaches 86% at room temperature and further improves with rising temperature. The microcrystals also show excellent photostability, retaining 95% of initial intensity after 120 min continuous UV irradiation. Furthermore, we demonstrate a proof-of-concept wireless optical communication link using the microcrystals as a NIR-II phosphor, achieving a signal-to-noise ratio of 30 dB at 400 Hz modulation frequency. These findings provide a new strategy for designing thermal-enhanced NIR-II luminescent materials and expand their potential in temperature sensing and optical communication.
SCIENCE CHINA Materials•2026•DOI: 10.1007/s40843-026-4201-0
Open fracture fixation faces dual critical challenges: bacterial infection and impaired bone healing. This study presents a rationally designed biomacromolecular network coating (Ti-GOED) on titanium alloy bone plates to simultaneously address these issues. The coating integrates antimicrobial and osteogenic components, achieving an optimal balance between antibacterial efficacy and biocompatibility. In vitro assays demonstrated that Ti-GOED eliminates over 99% of common pathogenic bacteria by inhibiting peptidoglycan synthesis, disrupting bacterial cell wall formation, compromising membrane integrity, and leading to intracellular DNA leakage and bacterial death. Concurrently, Ti-GOED enhances the proliferation and osteogenic differentiation of bone marrow mesenchymal stem cells (BMSCs) via activation of the PI3K-Akt and HIF-1 signaling pathways. In vivo animal experiments confirmed strong antibacterial and osteogenic properties. This work provides a strategy for developing antibacterial coatings on medical devices, with significant potential for preventing and treating infections post-fracture fixation.
SCIENCE CHINA Materials•2026•DOI: 10.1007/s40843-025-3830-6
Controlled fabrication of artificial multiple-stranded helices is central to deciphering chirality complexity and hierarchical self-assembly processes. Inspired by biological helical nanostructures, we designed a twisted figure-of-eight chiral macrocycle (M1) from pyrene and benzene diimide subcomponents to direct hierarchical assembly of double- and quadruple-stranded superhelices. Single-crystal X-ray diffraction reveals that M1 undergoes charge-transfer and CH···π interactions-driven helical wrapping, forming right-handed (P) single strands that intertwine into quadruple π-helical superstructures. Crucially, the macrocycle's adaptive cavity and interstitial voids could bind electron-deficient naphthalene diimide (NDI) guests through charge transfer interactions, triggering transformation to left-handed (M) double helices. This structural shift induces helicity inversion and optical anisotropy changes, demonstrating a rare case of crystalline-state multiple-helix conversion with supramolecular chirality inversion. This work establishes a template-free methodology for synthesizing multiple-stranded π-helices and controlling their transformations through supramolecular engineering.
SCIENCE CHINA Materials•2026•DOI: 10.1007/s40843-026-4229-6
The escalating retirement of lithium-ion batteries (LIBs) necessitates efficient recycling technologies to recover cathode materials, particularly lithium iron phosphate (LFP), which dominates the traction battery market. Conventional pyrometallurgical and hydrometallurgical methods are energy-intensive and environmentally burdensome. Here, we report a fluorine doping-assisted direct regeneration strategy for spent LFP (SLFP) cathodes, yielding a regenerated LFP-F (RLFP-F) with a hybrid structure of ordered crystalline and disordered domains. Fluorine doping reduces the Li+ diffusion energy barrier, as evidenced by density functional theory calculations, and strengthens Fe–O bonding, suppressing Fe migration and anti-site defect formation. The O 2p band center shifts downward, increasing the Fe 3d–O 2p energy separation from 3.23 eV in pristine LFP to 3.46 eV in RLFP-F, enhancing structural stability and electronic conductivity. Electrochemical tests demonstrate that RLFP-F delivers a high-rate capability and excellent cycling stability. Life-cycle assessment reveals that direct regeneration consumes only 9.986 MJ kg−1 and emits 0.324 kg CO2-equivalent per kg of cell, significantly outperforming pyrometallurgy and hydrometallurgy. Economic analysis based on 2025 Chinese market prices indicates a net profit of $397.15 per ton of SLFP battery recycling, attributed to the closed-loop cathode-to-cathode design. This work provides a sustainable and economically viable route for upcycling spent LFP batteries.