Yuanping Li

Biochar was synthesized through high-temperature pyrolysis, and a biochar-supported nitrogen and sulfur co-doped BiOBr (BC/N,S-BiOBr) photocatalyst was successfully prepared via a one-step solvothermal method, which was applied for the degradation of tetracycline (TC), a widely detected representative antibiotic pollutant, in aqueous solution. This study systematically investigated the effects of catalyst type, initial solution pH, catalyst dosage and initial TC concentration on the photocatalytic degradation process. The experimental results showed that the as-prepared BC/N,S-BiOBr composite exhibited a flower-like nanosphere morphology, characterized by a more complete three-dimensional hierarchical structure, larger specific surface area and suitable optical absorption band, which endowed the composite with significantly improved visible-light absorption capability. Under the optimized reaction conditions (pH = 5, catalyst dosage of 0.7 g/L, initial TC concentration of 10 mg/L), the degradation efficiency of TC over BC/N,S-BiOBr reached 98% after 50 min of visible-light irradiation. In situ electron paramagnetic resonance (EPR) spectroscopy combined with radical quenching experiments confirmed that the modified composite contained abundant oxygen vacancies, and the main reactive species governing TC degradation were identified as photogenerated holes (h⁺), hydroxyl radicals (·OH) and superoxide radicals (·O₂⁻), with their contribution to TC degradation following the order of h⁺ > ·OH > ·O₂⁻. In summary, by converting municipal sludge into biochar-supported N,S-BiOBr photocatalyst, the modified BC/N,S-BiOBr composite exhibits faster photocatalytic reaction kinetics and higher tetracycline removal efficiency compared with pristine BiOBr, while simultaneously enabling waste resource recovery, solar energy exploitation, and water purification, thereby comprehensively promoting sustainable development in terms of environmental remediation, resource circulation, and low-carbon operation.

Sludge-derived biochar enables sensitive BDE-47 detection without pretreatment. The modified electrode achieved a 5 ng L ⁻¹ detection limit and was validated in real water samples, offering a robust tool for POPs monitoring.

2,2′,4,4′-Tetrabromodiphenyl ether (BDE-47) is a refractory organic pollutant that is characterized by its persistence, toxicity and potential for bioaccumulation. As a typical biocontrol bacteria, Pseudomonas protegens has not been reported to degrade organic pollutants in the environment. A single strain of Pseudomonas protegens was isolated and acclimated from municipal sludge, and its ability to degrade BDE-47 was investigated. The enhancing effects of different carbon sources and inducers on Pseudomonas protegens were also examined. Through the reinforcement of bacterial enhancers, Pseudomonas protegens was applied to remediate soil and water contaminated with BDE-47. Based on colony characteristics, physiological and biochemical properties, and 16S rDNA gene sequence homology analysis, the strain was identified as Pseudomonas protegens and named YP1. This marks the first discovery of Pseudomonas protegens being capable of degrading BDE-47. Strain YP1 utilized BDE-47 as a carbon source and achieved a degradation rate of 69.57% after 75 h of incubation under conditions of 37 °C, pH 7, and constant temperature in a dark shaking incubator. After comparing the actual enhancement effects, glucose was selected as the carbon source and 2,4-dichlorophenol as the inducer to improve the environmental remediation capability of Pseudomonas protegens. After 14 days of remediation, the degradation rates of BDE-47 in contaminated soil and water reached 48.26% and 52.60%, respectively. The Pseudomonas protegens strain obtained from municipal sludge through screening, acclimation, and enhancement processes exhibits excellent environmental remediation capabilities and promising practical application prospects.

Novel GNPs-Au modified electrode enables ultrasensitive detection of Pb ²⁺ and Cd ²⁺ (1 ng L ⁻¹ LOD) with 7.2-fold enhanced sensitivity. Achieves 90–113% recovery in real water samples. Ideal for environmental monitoring applications.