SCIENCE CHINA Materials•2026•DOI: 10.1007/s40843-026-4159-y
The electrocatalytic oxidation of ethylene glycol (EG) derived from polyethylene terephthalate (PET) waste to valuable glycolic acid (GA) represents an attractive route for waste resource upcycling. However, achieving high selectivity remains challenging due to the difficulty in steering the complex reaction pathway. In this study, PdPtCuInBi high-entropy intermetallic metallene (HEI-PdPtCuInBiene) is reported to precisely control EG oxidation reaction (EGOR) pathway for GA production by constructing multiple active sites at the atomic scale. In PET hydrolysate, it achieves a Faradaic efficiency of 99.87% and a production rate of 1.47 mmol h−1 cm−2, along with excellent stability. Mechanistic studies reveal that the high-entropy structure induces strong p-d orbital hybridization, which optimizes the electronic structure of active sites, thus weakening the adsorption of key carbonyl intermediates and suppressing C–C bond cleavage. The synergistic electronic effect among Pd, Pt, and Cu further enables differential adsorption of distinct intermediates on diverse active sites, enhancing the selective formation of GA. Techno-economic analysis exhibits high profitability (~$784.9 t−1 PET) of this route, demonstrating the great potential of high-entropy intermetallic metallene in regulating electrocatalytic upcycling of PET waste and beyond.
SCIENCE CHINA Materials•2026•DOI: 10.1007/s40843-025-3647-4
Chromium oxides (CrOx) and fluorinated graphite (CFx) are two typical cathode materials for lithium primary batteries. The former possesses the highest theoretical energy density but suffers from low practical capacity and inferior rate capability; the latter has the highest theoretical discharge capacity but fails to support fast discharge. Combining the merits of both cathodes via a composite design is desirable, yet the electrochemical performance of such composites remains unsatisfactory. In this work, we identified that by regulating the overlapped discharge potential of these two cathodes, fluorine atoms migrate from CFx to CrOx, leading to a homogeneous distribution of LiF and improved ionic and electronic conductivity, ultimately enhancing high-rate discharge performance. Benefiting from this synergetic effect, the CrOx/10%eCFx composite exhibits a considerably high energy density of 496.59 Wh kg−1 at a power density of 49.7 kW kg−1 (50 C), far superior to pure CrOx and CFx electrodes. We believe that the high-performance CrOx/eCFx composite cathode will justify its practical application in revitalizing advanced lithium primary batteries.
SCIENCE CHINA Materials•2026•DOI: 10.1007/s40843-025-3748-9
Direct regeneration is a sustainable solution for recycling spent lithium-ion batteries (LIBs), yet the irregular strains induced by the irreversible FePO4 phase after cycling hinder Li+ replenishment in spent LiFePO4 cathodes. This study proposes a lattice stress modulation strategy that reduces FePO4 to Fe2P2O7, reducing unit cell volume from 271.7 to 122.6 Å3, releasing residual stress and reconstructing continuous Li+ transport channels. The phase transformation reconstructs FeO6 octahedra, lowering the migration energy barrier for ions. This synergistically weakens steric effects, facilitating Li+ replenishment and eliminating Li-Fe anti-site defects. Regenerated LiFePO4 cathodes achieve 80.2% capacity retention after 1000 cycles at 2C, outperforming commercial cathodes. The work establishes fundamental principles for the pre-treatment stage of direct regeneration and provides a paradigm-shifting solution for sustainable LIB recycling.
Chinese Journal of Environmental Engineering•2026•DOI: 10.12030/j.cjee.202509051
Recyclables constitute a significant fraction of municipal solid waste (MSW) and hold substantial potential for resource utilization and greenhouse gas (GHG) emission reduction, contributing to carbon peak and carbon neutrality goals. However, reported GHG emission factors (EFs) for various recyclables vary widely across databases and literature, ranging from -19,110 to -125 kgCO2-eq·t⁻¹, with significant differences both among categories and within the same category, complicating accurate accounting. This study systematically integrates literature data on EFs for different recyclable categories, focusing on identifying factors causing intra-category variability. Data were collected from global databases (ecoinvent, WARM, CPCD, NAEI) and peer-reviewed studies over the past two decades, normalized to a functional unit of 1 tonne of recyclable. Statistical analysis (mean ± standard deviation) provided reference ranges for each category. Results show paper recyclables EFs range from -3,140 to 270 kgCO2-eq·t⁻¹, with corrugated cardboard and writing paper exhibiting higher absolute values than packaging paper due to structural strength and resource value. Plastic recyclables EFs range from -3,096 to -566 kgCO2-eq·t⁻¹, with EPS showing the highest reduction potential, followed by PET and PVC, then HDPE, LDPE, PP, and other plastics. Key influencing factors include functional unit definition, accounting scenario, system boundary, electricity emission factor selection, and calculation assumptions. The study recommends selecting EFs matching the specific accounting scenario and performing error analysis. Data gaps remain for LDPE, EPS, and other plastics, necessitating further experimental or field data. To enhance accuracy, calibration methods such as process-level and life-cycle inventory data calibration are proposed. This work provides a scientific basis for EF selection and calibration in GHG accounting of recyclables.
SCIENCE CHINA Materials•2026•DOI: 10.1007/s40843-025-3790-5
Near-infrared (NIR) phosphors with high quantum efficiency (QE) and thermal robustness are critical for phosphor-converted light-emitting diodes (pc-LEDs). Here, a Cr3+-activated Lu2BaAl4SiO12 (LBASO) garnet phosphor is engineered via chemical unit cosubstitution of [Ba2+-Si4+] for [Lu3+-Al3+] in Lu3Al5O12 (LuAG), inducing a strong crystal field that yields NIR emission at 705 nm. The optimized LBASO:0.07Cr3+ exhibits an internal quantum efficiency (IQE) of 84.82% and external quantum efficiency (EQE) of 46.02%. Notably, it demonstrates anti-thermal quenching (ATQ) with 126.03% of its initial intensity at 498 K under 442 nm excitation, attributed to a wide band gap, weak electron-phonon coupling, defect trap energy levels, high structural rigidity, and optimized electron population distribution. A NIR pc-LED fabricated with this phosphor achieves an output power of 134.99 mW and photoelectric conversion efficiency of 11.4% at 100 mA drive current. These results underscore the potential of LBASO:Cr3+ for applications in plant lighting, night vision, and nondestructive analysis.
Chinese Journal of Environmental Engineering•2026•DOI: 10.12030/j.cjee.202510060
Wastewater treatment plant (WWTP) effluent is a significant pathway for emerging contaminants (ECs) to enter natural water bodies. This study investigated the removal of ECs by two field-scale gravel-based constructed wetlands: a horizontal subsurface flow constructed wetland (QL-CW) and a surface flow constructed wetland (BL-CW), both treating actual WWTP effluent. The influence of operation mode and wetland plant type on EC removal was examined. Using liquid chromatography-mass spectrometry, principal component analysis, and ecological risk assessment, the removal efficiencies and mechanisms for various ECs were explored. In QL-CW, biodegradation was more pronounced, particularly via ammonia-oxidizing bacteria co-metabolism, favoring ECs with benzyl, secondary amine, secondary amide, tertiary amide, halogenated, and carboxyl functional groups. In BL-CW, electrostatic attraction and hydrophobic interactions were more significant, with plant and root-microorganism uptake and adsorption playing key roles. Surface flow mode achieved significantly higher removal of antibiotics (45.3% vs. 34.1%) compared to horizontal subsurface flow, while no significant differences were observed for non-antibiotic pharmaceuticals (66.6% vs. 64.4%) and pesticides (49.8% vs. 34.2%). Planting Cyperus alternifolius (windmill grass) was more beneficial for antibiotic removal (43.6% vs. 30.1%) than planting Ipomoea aquatica (water spinach). The wetlands effectively reduced the ecological risks of most ECs to marginal levels. This study provides insights into the deep treatment of ECs in WWTP effluent by constructed wetlands.
Environmental Chemistry•2026•DOI: 10.7524/j.issn.0254-6108.2025040104
The oxidative transformation of 2,6-dichlorophenol (2,6-DCP) was investigated in three typical zonal soils: black soil, red soil, and brown soil. Results demonstrated that 2,6-DCP underwent oxidative coupling in all soils, yielding hydroxylated polychlorinated diphenyl ethers (OH-PCDEs) and hydroxylated polychlorinated biphenyls (OH-PCBs) as primary products. The highest oxidative efficiency occurred in black soil, with approximately 85.1% of 2,6-DCP transformed within three days. In contrast, red and brown soils exhibited lower efficiencies, indicating a strong dependence on soil properties. Thermodynamic analysis revealed that the oxidative coupling reaction is endothermic, with elevated temperatures favoring reaction progress. Furthermore, soil microorganisms and dissolved oxygen were identified as critical controlling factors, acting synergistically to drive the reaction. This study provides the first evidence of natural oxidative coupling of 2,6-DCP in soil, forming OH-PCDEs and OH-PCBs. These findings offer significant scientific insight into the environmental fate of halogenated phenolic pollutants in terrestrial systems.
Chinese Journal of Environmental Engineering•2026•DOI: 10.12030/j.cjee.202511025
Under the national carbon peak and carbon neutrality goals, carbon reduction in municipal wastewater treatment plants (WWTPs) has been largely overlooked, yet accurate accounting is the first step toward mitigation. This study establishes a carbon emission accounting method for a municipal WWTP in Lanzhou, covering the operation and maintenance phase, to identify key emission sources and propose feasible reduction pathways. The results show that the total annual carbon emission in 2023 was 61,399.80 t CO2-eq, with an emission intensity of 0.71 kg CO2-eq per tonne of wastewater treated. Monthly emissions were relatively stable, with a coefficient of variation of 3.46%. Direct emissions accounted for 47.47% of the total, with N2O being the dominant contributor (61.89% of direct emissions), followed by CO2 (30.88%) and CH4 (7.23%). Indirect emissions accounted for 52.53%, dominated by electricity consumption (95.15% of indirect emissions). Pearson correlation analysis revealed that direct carbon emissions per tonne were significantly correlated with influent BOD5 concentration, influent TN concentration, BOD5 removal rate, and TN removal rate (P < 0.01). Sensitivity analysis identified sewer retention time, fossil carbon fraction in influent, and solids retention time as the most influential parameters, with sensitivity coefficients of 0.42, 0.35, and 0.28, respectively. Considering uncertainties in emission factors and monitoring errors, the 95% confidence interval for annual total emissions was 55,200–67,600 t CO2-eq, corresponding to an emission intensity of 0.64–0.79 kg CO2-eq per tonne. Recommendations focus on three synergistic reduction strategies: reducing source emissions, lowering energy consumption, and enhancing carbon compensation.
Environmental Chemistry•2026•DOI: 10.7524/j.issn.0254-6108.2026031103
Sintering ash washing wastewater from steel plants is characterized by high salinity, high chloride content, high thallium load, and coexistence of multiple metals, posing significant treatment challenges. This study employed thermodynamic simulation to elucidate the speciation and transformation of thallium in such wastewater, and systematically investigated a combined process of sulfide precipitation coupled with coagulation-flocculation. The results showed that at pH 9–10, thallium predominantly existed as Tl+. Under oxidizing conditions, the stable complex anion [TlCl4]− dominated at pH < 8.1, while at pH > 8.1, a mixed system of solid Tl2O3 and dissolved TlClO3 coexisted. Under optimized conditions (pH 12, 2.0% thallium removal agent, 1.0% multi-effect auxiliary agent), the thallium concentration in the wastewater decreased from an initial 9.58 mg·L−1 to 4.31 μg·L−1, meeting the stringent discharge limit of ≤5 μg·L−1. Concurrent removal of Cu, Zn, and Cd was achieved. The primary removal mechanism was sulfide precipitation, with lattice substitution between Tl+ and K+ serving as an auxiliary pathway. This study provides a practicable technical route for advanced treatment of high-chloride, high-thallium industrial wastewater.