SCIENCE CHINA Materials•2026•DOI: 10.1007/s40843-026-4197-4
Deep-blue organic light-emitting diodes (OLEDs) remain the most challenging primary-color emitters due to stringent exciton energy requirements. We strategically designed two innovative deep-blue emitters, SCZ-4AnCN and STPA-4AnCN, via systematic functionalization of an anthracene core with arylamino-decorated spirofluorene donors and cyano-substituted phenyl acceptors. Comprehensive theoretical and experimental analyses demonstrate that these spirofluorene-anthracene hybrids adopt precisely engineered distorted configurations, effectively suppressing detrimental intermolecular π–π stacking in condensed phases. The sp3-hybridized bridgehead carbons in spirofluorene units play a pivotal role by simultaneously restricting π-conjugation extension and fine-tuning donor–acceptor interactions, thereby stabilizing the lowest excited singlet (S1) state with dominant local excitation (LE) character. This molecular engineering yields exceptional deep-blue emission with remarkable efficiency. Notably, the materials exhibit unique high-lying reverse intersystem crossing (hRISC) behavior, enabling efficient triplet harvesting. Optimized doped devices incorporating SCZ-4AnCN achieve outstanding performance, including a maximum external quantum efficiency (EQE_max) exceeding 10% and CIE coordinates (0.154, 0.052) approaching the BT.2020 blue standard. Nondoped devices maintain impressive performance with an EQE_max of 7.51% and superior operational stability, demonstrating less than 10% efficiency roll-off at 1000 cd m−2. This work validates anthracene-based molecular architectures for deep-blue electroluminescence and establishes a transformative design paradigm for next-generation OLED emitters.
SCIENCE CHINA Materials•2026•DOI: 10.1007/s40843-025-4079-4
Utilization of ultrahigh-nickel LiNi_xCo_yMn_1-x-yO_2 (NCM) (x > 0.97) in Li-ion batteries can distinctively boost energy density through enhanced discharge capacity. However, capacity and thermal stability deteriorate as Ni content approaches the limit. Here, we propose a facile strategy by introducing high-valence tungsten (W) into ultrahigh-nickel polycrystalline LiNi_0.98Co_0.01Mn_0.01O_2 (PCNCM98). W-doped PCNCM98 (W-PCNCM98) exhibits refined, compactly stacked primary particles, whereas PCNCM98 shows equiaxial, non-uniform larger particles. The refined microstructure enhances mechanical strength: average particle hardness of W-PCNCM98 is 104 MPa, 1.5 times higher than PCNCM98 (68 MPa). This improved mechanical property suppresses lattice volume changes and relieves microcrack formation from H2–H3 phase transition. Consequently, cycling performance in pouch-type full cells is significantly enhanced, with capacity retention of 73% after 2000 cycles at 1 C and 25 °C, 54% higher than PCNCM98. Enhanced structural stability and strong electron affinity of W6+ also improve thermal stability: exothermic peak for W-PCNCM98 is postponed to 203 °C with heat generation of 1287 J g−1, versus 190 °C and 1528 J g−1 for PCNCM98. This high-valent doping strategy stabilizes ultrahigh-nickel NCM cathodes, accelerating large-scale EV applications.
Chinese Journal of Environmental Engineering•2026•DOI: 10.12030/j.cjee.202510017
Municipal solid waste (MSW) is a significant source of urban carbon emissions. This study integrates life cycle assessment (LCA) and system dynamics (SD) to construct a multi-subsystem LCA-SD model covering economy, population, waste generation, transportation, treatment, and resource utilization, using Fuzhou City as a case study. The model was validated against historical data and uncertainty analysis. Carbon emissions from MSW transportation, treatment, and resource utilization during 2013–2023 were calculated, and emission trends under seven reduction scenarios for 2024–2035 were predicted. Results show that Fuzhou's MSW treatment evolved through three stages: 'landfill+incineration', 'treatment structure adjustment', and 'incineration+kitchen waste resource utilization', corresponding to emission growth, fluctuation, and reduction periods. In 2023, total net carbon emissions were 1.07×10^6 t CO2-eq, with incineration being the largest contributor (9.93×10^5 t), followed by transportation (2.93×10^4 t), leachate treatment (2.14×10^4 t), and kitchen waste treatment (7.90×10^3 t, negative emission). Scenario analysis indicates that without further measures, carbon neutrality cannot be achieved. Synergistic enhancement of kitchen waste separation and incineration power generation efficiency can significantly boost reduction, potentially achieving carbon neutrality by 2032. The study provides a dynamic accounting and scenario assessment framework for low-carbon transition of urban solid waste systems.