SCIENCE CHINA Materials•2026•DOI: 10.1007/s40843-026-4275-3
Electrochemical in-situ production of active chlorine (AC) via chlorine evolution reaction (CER) can alleviate hull corrosion and residual chlorine overage, which is a highly reliable disinfectant for sewage and ballast water. Nonetheless, the primarily competitive oxygen evolution reaction and gradual anode passivation hinder its practical application. Herein, we employed the in-situ hydrothermal strategy to synthesize Ru/TiO2-x to realize high activity and selectivity of CER. The robust interaction of Ru sites and TiO2-x achieved via a one-step hydrothermal synthesis strategy, the structural and valence state characterizations confirm that Ti3+ stabilizes Ru solely in the metallic state (Ru0) via structural confinement effects, effectively inhibiting catalyst oxidation. As a result, the Ru/TiO2-x requires only an overpotential of 33 mV to reach 10 mA cm−2, and possess strong catalytic durability, sustaining continuous operation for 100 h with negligible current decay. Further integration with a triboelectric nanogenerators successfully realizes the generation of AC, which demonstrates a >99.9% inactivation efficiency against Escherichia coli in simulated seawater environments, while also effectively degrading ammonia nitrogen and urea contaminants in domestic wastewater.
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.
Chinese Journal of Environmental Engineering•2026•DOI: 10.12030/j.cjee.202508021
Coal chemical industry waste salt, generated from high-salinity wastewater treatment, poses a bottleneck for green transformation under the 'dual carbon' strategy due to its low value and high complexity. This study investigated a typical coal chemical industrial park in Northwest China, using principal component analysis (PCA) on actual waste salt samples to identify pollutant characteristics and assess resource utilization potential. Results showed total organic carbon (TOC) ranged from 707.9 to 7,737.9 mg·kg⁻¹, with benzo(a)pyrene concentrations frequently exceeding the limits of the 'Identification Standards for Hazardous Wastes' (GB 5085.3). Hardness ions and metal ions also surpassed relevant product standards. PCA classified the waste salts into three types: sodium sulfate type, sodium chloride type, and high-complexity mixed salt, each corresponding to distinct resource utilization pathways. The study proposes differentiated technical routes based on PCA classification, providing a feasible reference for classified management and technology selection. This research supports the national policy of 'harmless pretreatment + resource utilization' for waste salt, contributing to green and high-quality development of the coal chemical industry.
Environmental Chemistry•2026•DOI: 10.7524/j.issn.0254-6108.2025010803
Global aquaculture is expanding rapidly, with China leading in production and being the only country where aquaculture output exceeds wild catch. This growth raises concerns about environmental contamination, particularly mercury (Hg), and the safety of aquaculture products. This study investigated Hg accumulation and trophic transfer in a typical ecological mariculture area in Tangshan, Hebei Province, by measuring species-specific Hg concentrations in sediments and various aquatic organisms. Sediment total mercury (THg) levels were extremely low, averaging 4.0 ± 1.3 ng·g−1 dry weight (n=56), attributed to sandy/silty sediments with low adsorption capacity and minimal external/internal Hg inputs. In aquaculture fish, muscle THg and methylmercury (MeHg) concentrations were 59.7 ± 30.0 and 53.8 ± 29.2 ng·g−1 wet weight (n=7), respectively, comparable to wild fish from the same area. This is due to efficient trophic transfer and biomagnification of Hg, especially MeHg, along the food chain, influenced by food chain structure, primary consumer accumulation, and metabolic rates. At three seafood consumption levels (41.6–255.6 g·d−1), estimated daily intakes (EDI) of MeHg for Chinese adults ranged from 0.01 to 0.40 μg·kg−1·d−1, with target hazard quotients (THQ) from 0.13 to 3.98. Except for Penaeus monodon and Metapenaeus ensis, all other aquaculture products at high consumption levels exceeded the USEPA safety threshold for MeHg EDI and had THQ > 1, indicating potential health risks.
Environmental Chemistry•2026•DOI: 10.7524/j.issn.0254-6108.2025022501
The pretreatment of trace emerging contaminants in environmental matrices is challenging due to diverse methods and uncertain applicability. This study compared solid-phase extraction (SPE) and liquid-liquid extraction (LLE) for extracting endocrine-disrupting compounds (EDCs), particularly phthalate esters (PAEs), using laboratory-spiked blank samples. LLE achieved satisfactory recoveries for PAEs at spike levels below 4 μg·L−1, enabling detection of five PAEs including diisodecyl phthalate (DIDP), with improved efficiency via repeated extraction. SPE offered lower detection and quantification limits, higher accuracy and sensitivity, and achieved high recoveries for 12 EDCs and 10 antibiotics at spike levels ≥0.2 μg·L−1, with detection limits as low as 0.1–6.4 ng·L−1. The developed SPE coupled with liquid chromatography-Orbitrap mass spectrometry (LC-Orbitrap MS) method was applied to industrial wastewater samples. Across five industrial sectors (coatings, rubber, pharmaceuticals, inks, and materials technology), five antibiotics and ten EDCs were detected, with total concentrations ranging from 0.03–0.56 μg·L−1 and 0.07–1.91 μg·L−1, respectively. Sector-specific profiles emerged: rubber industry effluent was dominated by dibutyl phthalate (DBP) at 1.07 μg·L−1, while pharmaceutical effluent featured sulfamonomethoxine (SMM) at 0.34 μg·L−1. This systematic evaluation demonstrates that SPE-LC-Orbitrap MS is robust for complex matrices, providing a technical foundation for accurate quantification of emerging contaminants in industrial wastewater.
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.
SCIENCE CHINA Materials•2026•DOI: 10.1007/s40843-025-4000-1
Formamidine lead-based perovskites (FAPbI3) exhibit significant potential in optoelectronic applications. Nevertheless, they encounter challenges related to δ-phase instability and reliance on toxic solvents. In this study, we present a green solvent-additive synergy strategy that employs γ-valerolactone (GVL) in conjunction with reductive acids like oxalic acid (OA), to stabilize α-FAPbI3 single crystals (SCs). GVL enhances the stability of the precursors through the formation of FA+-GVL hydrogen bonds and high-valence [PbIx]2−x clusters, resulting in ambient-stable α-phase SCs, yielding a marked improvement in stability compared to SCs prepared with the toxic solvent γ-butyrolactone (GBL). Additive modulation demonstrates that H+ and reductive groups play a critical role in regulating crystallization, suppressing the δ-phase by promoting FA+ dissociation and inhibiting MA+ deprotonation. A solvent-involved intermediate, δ-FAPbI3-GVL, has been identified; this intermediate evolves into α-FAPbI3 at a low temperature of 60 °C, thereby reducing the energy barriers associated with the α to δ phase transition. In contrast, non-reductive acids and reductive ionic liquids do not inhibit δ-phase formation, with the latter even promoting the crystallization of pure δ-FAPbI3. By utilizing low-volatility OA as an additive, optimized FA0.9MA0.1PbI3 single crystal thin films exhibit a low defect density of 8.3 × 10^11 cm−3. Subsequently, a photodetector was fabricated. Under zero bias voltage and 780 nm illumination, the device exhibited a responsivity of 14.5 mA/W, a detectivity of 3.75 × 10^10 Jones, and a response speed of 149/65 μs. Moreover, without any encapsulation, the device’s performance diminished by only 17% after 30 days of storage in ambient conditions, indicating remarkable stability.