SCIENCE CHINA Materials•2026•DOI: 10.1007/s40843-026-4277-1
Two-dimensional (2D) magnetic materials hold promise for next-generation spintronics, yet most exhibit Curie temperatures (Tc) far below room temperature, limiting practical applications. Here, we report the realization of room-temperature ferromagnetism in CuCrSe2 nanosheets via controlled anion removal achieved by post-synthetic vacuum annealing. Raw CuCrSe2 shows a low Tc of ~120 K, whereas annealed CuCrSe2 (A-CuCrSe2) nanosheets exhibit robust ferromagnetic ordering above 300 K. Structural and compositional analyses, including transmission electron microscopy, Raman spectroscopy, and X-ray absorption spectroscopy, confirm that A-CuCrSe2 retains the original layered crystal structure with an estimated Se vacancy concentration of approximately 10%. Magnetic measurements reveal room-temperature ferromagnetism in exfoliated nanosheets, corroborated by magnetic imaging and electric transport measurements. Anomalous Hall effect (AHE) measurements uncover the coexistence of two ferromagnetic phases within the same sample: one with low Tc (~120 K) and another with high Tc (>300 K), indicating spatially heterogeneous magnetic ordering driven by anion removal distribution. Density functional theory (DFT) calculations elucidate the microscopic mechanism, suggesting that Se vacancies modulate the magnetic exchange interactions, enhancing Tc. This work demonstrates that anion modulation is an effective intrinsic strategy to achieve room-temperature ferromagnetism in 2D materials, potentially advancing spintronic applications.
Chinese Journal of Environmental Engineering•2026•DOI: 10.12030/j.cjee.202506081
Advanced oxidation processes (AOPs) are promising for degrading organic pollutants in water treatment. Heterogeneous catalytic ozonation (HCO) has gained attention due to its high oxidation efficiency, strong interference resistance, and low secondary pollution. In this study, a series of trimetallic-carbon composite ozone catalysts were prepared via an organic precursor calcination method using γ-Al2O3 as support. This method enhanced catalytic activity and mechanical strength while overcoming the limitations of carbon materials (low mechanical strength) and metal-based materials (poor mass transfer). The optimized catalyst, CA-FeCoCu, comprising Fe, Co, Cu, carbon, and alumina, exhibited excellent performance in phenol degradation and real industrial wastewater treatment. Characterization revealed that the synergistic effect of trimetals and the introduction of multiple carbon types increased specific surface area and hydroxyl radical (·OH) generation. In a pilot-scale fixed-bed reactor, the CA-FeCoCu/O3 system reduced COD from 120 mg·L−1 to below 40 mg·L−1, with an O3 consumption ratio (O/C) of less than 1, effectively lowering operational costs. This work provides a new strategy for developing efficient and stable heterogeneous O3 catalysts and offers a reference for the practical application of HCO in industrial wastewater treatment.
New Carbon Materials•2026•DOI: 10.1016/S1872-5805(26)61102-X
Silicon-carbon composites prepared by chemical vapor deposition (CVD) are promising anode materials for high-energy-density lithium-ion batteries. However, the influence of the pore structure of the porous carbon (PC) carrier on silicon deposition behavior, and the impact of surface silicon on cycling stability, remain unclear. This study systematically investigates these effects using nitrogen adsorption-desorption analysis, X-ray photoelectron spectroscopy, and thermogravimetric analysis. Porous carbons with varying pore architectures were synthesized by adjusting KOH activator ratios. Results show that increased micropore volume facilitates higher silicon mass loading, but also elevates the content of surface floating silicon due to greater silane exposure. Moderately increasing mesopores in high-microporosity carbon promotes deeper silicon deposition, reducing surface floating silicon. Excessive surface floating silicon hinders lithium-ion diffusion kinetics, leading to accumulation of active lithium, accelerated SEI growth, and electrode degradation. Electrochemical testing reveals that the optimized silicon-carbon composite maintains a high specific capacity of 693.1 mAh/g after 150 cycles at 0.5 C (900 mA/g). This work provides new insights into the development and failure mechanisms of CVD-derived silicon-carbon composite anodes, emphasizing the critical role of pore structure in mitigating surface silicon and enhancing cycling stability.
SCIENCE CHINA Materials•2026•DOI: 10.1007/s40843-025-3774-3
Lithium-air capacitor batteries (LACBs) integrate the rapid charge-discharge capability of supercapacitors into conventional lithium-oxygen batteries, significantly enhancing power density. However, their cycling stability remains unsatisfactory. In this study, we incorporated redox mediators (RMs) into an LACB featuring a dual-cathode configuration. This design facilitates sustained electron transfer between the electrode and Li2O2/Oxygen, thereby delaying RM deactivation caused by electrode passivation and improving overall electrochemical performance. The RM-enhanced battery achieved over 250 cycles at 2 mA cm−2 with a limited capacity of 0.5 mAh cm−2, while exhibiting a 0.54 V reduction in charging voltage at 0.1 mA cm−2 compared to the RM-free system. Furthermore, application of an aluminum foil sealing technique enabled a power density of 13.8 mW cm−2 at 6 mA cm−2, overcoming mass transport limitations inherent in open-cell configurations. We also investigated the influence of oxygen barrier films with varying barrier capabilities on LACB performance. Results indicate that films with superior oxygen resistance better maintain a clean capacitor electrode surface, thereby providing more stable electron supply to the RMs and enhancing rate capability and cycling performance. These findings underscore the potential of redox mediators in improving the performance and longevity of LACBs, offering a promising strategy for their future development.
SCIENCE CHINA Materials•2026•DOI: 10.1007/s40843-026-4093-8
Cyclohexanone oxime (CHO) is a pivotal feedstock for nylon-6 production, yet conventional synthesis routes suffer from high explosion risks, harsh conditions, and costly catalysts. Here, we report an electrocatalytic approach for CHO synthesis via reductive coupling of cyclohexanone (CYC) with nitrite over commercially available Bi2O3. A two-stage pulsed electrolysis protocol is employed: the first stage prepares amorphous Bi2O3, while the second stage produces CHO with a Faradaic efficiency (FE) of 74.63% and a yield rate of 0.156 mmol h−1 cm−2. Mechanistic studies, combining experiments and density functional theory (DFT) calculations, reveal that on amorphous Bi2O3, the *NOH intermediate preferentially undergoes hydrogenation to *NHOH and then *NH2OH, rather than the *NOH→*N pathway leading to NH3. This selectivity is attributed to the higher integral crystal orbital Hamilton population (ICOHP) for the N–O bond in *NOH on amorphous Bi2O3 (1.34 vs. 0.84 on amorphous Bi), indicating a weakened N–O bond that facilitates hydrodeoxygenation. Transition state calculations show a kinetic barrier of 0.86 eV for *NH2OH→*NH2, while desorption of *NH2OH to NH2OH is barrierless, favoring NH2OH release. This work provides a sustainable, efficient alternative to conventional CHO production, addressing safety and cost concerns while achieving high selectivity.