We aim at fabricating a ternary magnetic recyclable Bi 2 WO 6 /BiOI@Fe 3 O 4 composite that could be applied for photodegradation of tetracycline (TC) from synthetic wastewater. To identify any changes with respect to the composite's morphology and crystal structure properties, ΧRD , FTIR , FESEM-EDS, PL and VSM analyses are carried out. The effects of Fe 3 O 4 loading ratio on the Bi 2 WO 6 /BiOI for TC photodegradation are evaluated, while operational parameters such as pH, reaction time, TC concentration, and photocatalyst's dose are optimized. Removal mechanisms of the TC by the composite and its photodegradation pathways are elaborated. With respect to its performance, under the same optimized conditions (1 g/L of dose; 5 mg/L of TC; pH 7; 3 h of reaction time), the Bi 2 WO 6 /BiOI@5%Fe 3 O 4 composite has the highest TC removal (97%), as compared to the Bi 2 WO 6 (63%). After being saturated, the spent photocatalyst could be magnetically separated from solution for subsequent use. In spite of three consecutive cycles with 71% of efficiency, the spent composite still has reasonable photocatalytic activities for reuse. Overall, this suggests that the composite is a promising photocatalyst for TC removal from aqueous solutions.
Yang Liu,Hongguang Guo,Yongli Zhang,Xin Cheng,Peng Zhou,Gucheng Zhang,Jingquan Wang,Peng Tang,Tingling Ke,Wei Li
This study represents the first investigation on the application of persulfate (PS)/vis-light for the degradation of Rhodamine B (RhB) using bismuth oxyiodide magnetic composites (BiOI/Fe 3 O 4 , BOMCs). The 3D flower sphere-like BOMCs were successfully fabricated via a hydrothermal method, proving to be an excellent photocatalyst under visible light when evaluated by various characterization methods. The results demonstrated that BOMCs had a high photodegradation efficiency at pH 3.0–9.0 and the BiOI/Fe 3 O 4 (5:1) composite displayed the optimal catalytic performance. Inorganic ions such as Cl − showed promotion at a lower concentration, while significant inhibition was observed for higher concentrations of Cl − and HCO − 3 in the Vis/BOMCs/PS process due to the quenching effect. Moreover, 44.9% mineralization efficiency for total organic carbon and the excellent stability of BOMCs were demonstrated with limited iron leaching. Based on the scavenger experiments, the photocatalytic mechanism in the coupled system determined· SO − 4 and OH as the main reactive species. Eventually, the major intermediates are detected by GC/MS, and a possible photocatalytic degradation pathway of RhB is proposed in the Vis/BOMCs/PS process.
Microplastic accumulation in water bodies is posing a serious threat to public health. Their chemical inertness impairs the effectiveness of current micro/nano-material-based remediation strategies. Especially in urban drinking water systems, microplastics constantly released and accumulated together with the complexity of pipeline networks challenges the recyclability and long-term stability of remediation materials and technology. To address this, Cu-single-atom magnetic Janus microparticles (CuMJMs) with flower-like crown morphology are engineered meticulously via a step-by-step strategy involving solvothermal growth and chemical deposition. The resulting CuMJMs feature a distinct Janus architecture composed of BiOI nanosheets and Fe 3 O 4 nanoparticles, thereby delivering synergistic magnetic and photocatalytic functionalities. When subjected to a rotating magnetic field, CuMJMs are able to locomote collectively and recover rapidly in confined microenvironments. The incorporation of atomically dispersed Cu single atom not only enhances the number of active sites, but also promotes the separation and migration of photogenerated charge carriers. Such abilities enable CuMJMs to degrade polyethylene (PE) efficiently, achieving a weight loss rate of 53.7 % beyond previous reports. This performance improvement is ascribed to singlet oxygen generation boosted by the Cu single atoms to facilitate oxidative degradation pathways, as supported by electron paramagnetic resonance and active species trapping test. While used in real water matrices, CuMJMs maintain both catalytic activity and magnetic responsiveness, underscoring their robustness and practical potential. This work establishes a new paradigm to active microplastic remediation, merging atomic-level catalytic precision with collective particle behavior to enable scalable and efficient environmental cleanup.
危险品化学品经营许可证（带存储）