Process Intensification Laboratory, Department of Chemical Engineering, Yasouj University, Yasouj, 75918-74831, Iran.
Process Intensification Laboratory, Department of Chemical Engineering, Yasouj University, Yasouj, 75918-74831, Iran.
Chemosphere. 2022 Nov;307(Pt 3):135812. doi: 10.1016/j.chemosphere.2022.135812. Epub 2022 Aug 10.
The presence of antibiotics in wastes and drinking water has led to serious environmental and health concerns, further necessitating the development of an advanced sustainable strategy to eliminate antibiotics from aquatic media. In this context, the present research reports the successful fabrication of a spinning disc photoreactor (SDPR) supported ZnO/Ag/WO S-scheme visible-light-driven thin-film photocatalyst to study the degradation of cephalexin (CPX) as a target pollutant under blue light irradiation. The optical, electrochemical and physicochemical characterization of the as-prepared thin-film samples were carried out by XRD, top-view FE-SEM, EDS-mapping, UV-Vis-DRS, contact angle, EIS, transient photocurrent, mott Schottky and AFM techniques. The rod shape morphology of the samples with moderate surface roughness, desirable hydrophobicity, low bandgap and remarkable band structure alignment confirmed the applicability of as-prepared thin-film with an average photon flux of 1.94 × 10-8.61 × 10 E's m s. The use of a rotating catalytic disc impressively declined the photon propagation distance, decremented the probability of light absorption by the solution, and intensified the mass transfer rate. The maximum throughputs of 98.8% efficiencies for CPX degradation were achieved at a rotational speed of 180 rpm, the solution flow rate of 1.0 L min, the light intensity of 11 mW cm, and initial CPX concentration of 40 mg L, illumination time of 80 min, and pH of 6. Damkohler number (Da) value was found to be 1.23 × 10 at the optimum conditions, indicating the negligibility of the external mass transfer resistance in the SDPR. The photocatalytic mechanism was elucidated for finding the most operative radical species, suggesting the crucial role of ·O in photodegradation of CPX and a drastic improvement of the charge separation by S-scheme heterostructure and facilitation by Ag mediator. Findings indicated that the developed reusable and robust SDPR benefited from an s-scheme photocatalyst can be a promising technology for degradation of the organic compounds.
抗生素在废物和饮用水中的存在导致了严重的环境和健康问题，因此需要开发先进的可持续策略来从水生介质中消除抗生素。在这种情况下，本研究报告了成功制备了一种旋转盘光反应器（SDPR）负载 ZnO/Ag/WO S 型可见光驱动的薄膜光催化剂，以研究头孢氨苄（CPX）作为目标污染物在蓝光照射下的降解。通过 XRD、顶视图 FE-SEM、EDS 映射、UV-Vis-DRS、接触角、EIS、瞬态光电流、Mott-Schottky 和 AFM 技术对所制备的薄膜样品进行了光学、电化学和物理化学表征。样品具有适中的表面粗糙度、理想的疏水性、低带隙和显著的能带结构排列的棒状形态，证实了所制备的薄膜在平均光子通量为 1.94×10-8.61×10E 的情况下具有适用性s m s。旋转催化盘的使用显著降低了光子传播距离，减少了溶液对光的吸收概率，并增强了传质速率。在转速为 180rpm、溶液流速为 1.0Lmin、光强为 11mWcm、初始 CPX 浓度为 40mgL、光照时间为 80min、pH 值为 6 的最佳条件下，CPX 降解的最高效率达到 98.8%。在最佳条件下，发现达克尔数（Da）值为 1.23×10，表明在 SDPR 中外部传质阻力可以忽略不计。阐明了光催化机制以寻找最有效的自由基物种，表明·O 在 CPX 光降解中的关键作用以及 S 型异质结构和 Ag 介体促进的电荷分离的显著改善。研究结果表明，开发的可重复使用和稳健的 SDPR 受益于 S 型光催化剂，可为有机化合物的降解提供一种有前途的技术。
