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.202508004
Industrial processes generate substantial low-grade waste heat and cold, which can be harnessed via thermoelectric generators (TEGs) based on the Seebeck effect. However, the low-voltage output of TEGs poses application challenges. This study investigates a TEG-driven electrodeposition system for efficient treatment of low-concentration copper-containing wastewater from electroplating, integrated circuit, and energy industries. The TEG system, comprising two series-connected semiconductor modules, achieved a maximum power of 0.36 W at a temperature difference (ΔT) of 130 °C. Optimal operating parameters for the coupled system were determined: ΔT = 90 °C, counter-current flow (two-side inlet), flow rate of 20 mL·min⁻¹, initial Cu²⁺ concentration of 500 mg·L⁻¹, and electrode gap of 0.7 cm. Under these conditions, after 60 min of electrodeposition, copper removal efficiency reached 99.42%, current efficiency was 67.93%, and the energy conversion efficiency of the TEG-electrodeposition system was 36.96%. The system also treated real copper-containing wastewater, achieving 95.83% removal within 100 min. Characterization via SEM, XRD, and XPS revealed that the electrodeposited product consisted of metallic copper and cuprous oxide, with metallic copper accounting for approximately 60%. This work provides a promising approach for utilizing industrial waste heat and cold to achieve low-energy, high-efficiency treatment of heavy metal wastewater.
Journal of Environmental Engineering Technology•2026•DOI: 10.13205/j.hjgc.202606009
The escalating volume of municipal solid waste in China necessitates effective disposal strategies. Industrial kiln co-processing offers a promising route, but high-temperature decomposition of chlorinated components releases HCl and Cl2, causing severe equipment corrosion and operational issues. This study investigates the high-temperature dechlorination performance of fly ash and red mud, two abundant industrial solid wastes, as potential dechlorination agents. Using a high-temperature tube furnace system, dechlorination efficiencies were evaluated across 600–900 °C. At 700 °C, fly ash achieved a peak dechlorination efficiency of 93.33%, while red mud reached 88.61%. However, efficiencies declined with further temperature increase, dropping to 65.6% and 58.27% at 900 °C for fly ash and red mud, respectively. To enhance performance at higher temperatures, fly ash was modified via alkali (NaOH) treatment. The modification increased surface roughness and porosity, disrupted Si-O-Si and Si-O-Al networks, and exposed active sites. Consequently, the alkali-modified fly ash exhibited a peak dechlorination efficiency of 94.98% at 800 °C, a 23.08% improvement over unmodified fly ash (71.9%). These findings demonstrate the technical feasibility of utilizing solid wastes as dechlorination agents, offering a dual benefit of waste valorization and cost-effective high-temperature gas purification. The study provides a foundation for scaling up this approach in industrial kiln applications, contributing to sustainable waste management and reduced environmental impact.
Chinese Journal of Environmental Engineering•2026•DOI: 10.12030/j.cjee.202510081
Electrochemical two-electron oxygen reduction (2e−ORR) for hydrogen peroxide (H2O2) synthesis faces challenges of low cathodic catalytic efficiency and complex catalyst preparation. This study prepared nitrogen-vacancy (Nv) rich carbon nitride via one-step pyrolysis, composited with carbon nanotubes (CNT), and loaded onto graphite felt (GF) to fabricate a non-precious metal gas diffusion electrode Nv-C3N4-CNT/GF. The electrode exhibited a three-dimensional fibrous skeleton with interconnected micro-nano hierarchical pores, facilitating efficient electron transport. Electrochemical impedance spectroscopy revealed a low charge transfer resistance of 13.26 Ω, indicating superior electrocatalytic activity and charge transfer efficiency. Single-factor experiments and response surface methodology (RSM) optimization determined optimal conditions: calcination temperature 300 °C, catalyst mass ratio 3:1, Nv-C3N4-CNT loading 0.1 g, current density 40 mA·cm−2, pH 7, and aeration rate 0.1 L·min−1. Under these conditions, H2O2 accumulation reached 1622.73 mg·L−1 after 90 min, which was 1.3 and 1.5 times higher than g-C3N4-CNT/GF and CNT/GF electrodes, respectively. Stability tests showed that after 6 cycles, H2O2 production remained at 1400.52 mg·L−1, and within 960 min, the maximum production reached 2014.04 mg·L−1 with a highest Faradaic efficiency of 54.86%. These results demonstrate the electrode's potential for cyclic use. This study provides a new approach for developing efficient, low-cost electrodes for electrosynthesis of H2O2, offering a reference for green H2O2 production.
Journal of Environmental Engineering Technology•2026•DOI: 10.13205/j.hjgc.202607015
Microplastic pollution poses a severe threat to terrestrial ecosystems, with soil acting as a major sink. The application of sewage sludge organic fertilizer in public green spaces introduces microplastics (MPs) into the soil, yet their release and vertical migration dynamics remain poorly understood. This study investigated the release and transport of polypropylene (PP) and polyethylene (PE) MPs, the most prevalent types in sludge organic fertilizer, under simulated rainfall conditions representative of Chengdu. Over a six-month simulated rainfall period, the release rate of PE (26.1±1.8%) at 0.2% abundance (weight ratio) and 20–40 μm size was significantly higher than that of PP (16.4±1.3%). The highest release was observed for 40–60 μm particles, while excessive abundance induced aggregation, inhibiting release. A 24-month simulated transport experiment revealed that PE exhibited higher mobility than PP, with peak migration occurring between 14 and 18 months, and 40–60 μm particles showing the greatest transport capacity. Environmental factors critically modulated migration: increasing pH enhanced mobility, but the promoting effect of sludge leachate diminished under alkaline conditions; higher electrolyte concentrations reduced mobility, with sludge leachate exerting stronger inhibition at high EC; organic matter exhibited a non-linear effect, promoting transport at low concentrations and inhibiting at high concentrations. These findings provide essential data for mitigating microplastic contamination in public green spaces.