SCIENCE CHINA Materials•2026•DOI: 10.1007/s40843-026-4420-7
Cu2-xSe is a leading p-type thermoelectric material owing to its phonon-liquid electron-crystal (PLEC) behavior, yet the atomic-scale mechanisms governing Cu+ migration remain unresolved. This study employs in situ high-resolution neutron diffraction coupled with maximum entropy method (MEM) analysis to map the temperature-dependent evolution of Cu+ nuclear density in β-Cu2Se and β-Cu1.95Se. At 398–423 K, intra-tetrahedral Cu 8c ↔ 32f <111> hopping emerges, with isosurface values of 0.505 fm Å-3 for β-Cu2Se and 0.484 fm Å-3 for β-Cu1.95Se. Above 448 K, inter-tetrahedral pathways form via Cu 32f ↔ 32f <100> or 32f ↔ 4b ↔ 32f <111> migration, as revealed by line scans along [1̅11̅] up to 723 K. The presence of Cu vacancies (x = 0.05) alters the onset and connectivity of these pathways, directly impacting phonon scattering and electron transport. These findings establish a structural basis for controlling Cu+ mobility, offering a rational route to mitigate Cu precipitation and enhance zT stability beyond 1.5 at 900 K. The work bridges microstructural dynamics and thermoelectric performance, providing critical guidance for defect engineering in superionic thermoelectrics.
SCIENCE CHINA Materials•2026•DOI: 10.1007/s40843-026-4495-3
Room-temperature phosphorescence (RTP) has attracted substantial interest for applications in smart optoelectronics, yet the development of dynamic RTP systems remains intrinsically challenging. Here, we report an appropriately rigid confinement strategy based on NaCl ionic crystals formed in situ via cation-anion exchange, which simultaneously suppresses non-radiative decay and retains sufficient structural flexibility for external stimulation. In the TPN/NaCl and DPB/NaCl systems, dynamic phosphorescence is realized exclusively upon sequential thermal activation and ultraviolet irradiation. Mechanistic investigations reveal that residual water and triplet oxygen initially quench triplet excitons, and their gradual removal enables a competitive evolution between triplet-triplet annihilation (TTA) and phosphorescence pathways. This work establishes a general design principle for constructing stimulus-responsive dynamic RTP systems and resolves the long-standing conflict between rigidity and responsiveness in organic phosphorescent materials.
SCIENCE CHINA Materials•2026•DOI: 10.1007/s40843-025-3746-x
The polyanionic compound Na3V2(PO4)2O2F (NVPOF) possesses a stable three-dimensional framework, high theoretical specific capacity, and favorable operating voltage, yet its sluggish Na+ diffusion kinetics and low electronic conductivity impede industrial application. This study proposes a dual regulation strategy combining carbon coating and heat treatment temperature to synergistically enhance crystallinity and electrochemical performance. NVPOF@C-400 and NVPOF@C-600 were synthesized via in-situ dopamine hydrochloride coating followed by heat treatment at 400 °C and 600 °C, respectively. Carbon coating at 600 °C significantly improved crystallinity and increased electronic conductivity by three orders of magnitude through the carbon layer's conductive network. The ~4.5 nm carbon layer effectively suppressed abnormal grain growth and secondary crystallization aggregation at high temperatures, maintaining uniform particle size of approximately 0.36 μm, which shortens Na+ diffusion pathways and prevents ion transport obstruction. Consequently, NVPOF@C-600 delivered a high discharge capacity of 102.5 mAh g−1 at 20 C and retained 96.5% capacity after 10,000 cycles. In a full-cell configuration with hard carbon (HC), NVPOF@C-600//HC achieved an impressive 89.3% capacity retention after 9,000 cycles. This work provides critical insights for practical implementation of high-performance NVPOF cathodes in sodium-ion batteries.
Environmental Chemistry•2026•DOI: 10.7524/j.issn.0254-6108.2025122102
Uranium is a key resource for nuclear energy, but its mining and processing generate large amounts of uranium-containing wastewater, posing persistent threats to the environment and human health. In this study, a cyano-functionalized C3N4/ZnIn2S4 (CCN/ZIS) heterojunction system was constructed for efficient removal of U(VI) from uranium mining wastewater. The introduction of cyano groups significantly enhanced the adsorption capacity of CCN/ZIS, reaching a maximum of 123.65 mg·g−1. Characterization techniques (UV-vis DRS, EIS, i-t, PL, TRPL) confirmed that cyano groups effectively suppress charge carrier recombination, improving photogenerated carrier separation. Under visible light, the modified material achieved over 95% removal of U(VI) within 10 minutes, demonstrating a 20-fold efficiency increase compared to pristine materials. Even in simulated uranium mining wastewater containing high concentrations of CO3^2− and F−, CCN/ZIS maintained excellent performance, overcoming the technical challenge of U(VI) removal efficiency being constrained by water quality conditions. Quenching experiments identified e− and ·O2− as the primary reactive species responsible for U(VI) reduction. This study reveals the synergistic mechanism of selective U(VI) enrichment and photoreduction, providing theoretical innovation and technological breakthroughs for uranium pollution control.
SCIENCE CHINA Materials•2026•DOI: 10.1007/s40843-025-3932-1
Organic room-temperature phosphorescence (RTP) materials have attracted considerable interest due to their unique advantages, such as tunable molecular structures, excellent processability, intrinsic flexibility, and diverse excited-state characteristics. Among these, stimuli-responsive RTP materials, whose luminescence can be modulated by external stimuli (e.g., light, pH, heat, mechanical force or solvent), hold great promise for advanced applications like anti-counterfeiting, information encryption, and sensing. In this review, we systematically summarize recent advances in stimuli-responsive RTP materials, classifying them based on their activation mechanisms. Specifically, we elucidate the fundamental principles governing their stimulus-responsive behaviors and highlight representative examples from various categories. Furthermore, we explore structure-property relationships and design strategies to establish a foundational framework for understanding these materials. This review not only deepens the mechanistic insights into stimuli-responsive RTP systems but also provides strategic guidance for the rational design of next-generation intelligent RTP materials in multidisciplinary fields.
SCIENCE CHINA Materials•2026•DOI: 10.1007/s40843-025-3941-2
The precise and directed assembly of multicomponent aggregates remains a central challenge in materials chemistry, particularly the integration of neutral clusters. This study introduces a 'cation-mediated co-crystallization' strategy to overcome electrostatic assembly barriers between neutral aluminum molecular rings and polyoxometalates (POMs). By controllably functionalizing the rings with cationic moieties, the approach bypasses traditional 'ion-pair' limitations, enabling incorporation of diverse neutral clusters. The strategy exhibits structural extensibility, with cationic sites adjustable on ring exteriors or interiors, and potential extension to various polyanionic systems. The resulting hybrid materials demonstrate outstanding solution processability. When incorporated as dielectric dopants in a polymer matrix, they achieve a synergistic '1+1>2' effect: aluminum rings contribute high capacitance density (~11.19) and low dielectric loss (~0.03), while POMs provide high breakdown strength (~740 MV m−1). This work establishes a paradigm for directed macroscopic functional assembly via molecular-level cluster interaction 'encoding'.