NANOMISENE Laboratory LR16CRMN01, Center of Research on Microelectronics and Nanotechnology of Sousse, Technopark of Sousse, Tunisia; University of Sousse, High School of Sciences and Technology of Hammam Sousse, Tunisia.
Department of Industrial Engineering, University of Trento, Via Sommarive 9, Trento, Italy.
J Environ Manage. 2021 May 15;286:112226. doi: 10.1016/j.jenvman.2021.112226. Epub 2021 Mar 4.
Green-synthesized materials and solar concentration technology for advanced oxidation processes (AOPs) offer important opportunities in water remediation by giving value to clean, renewable and potentially low-cost resources. Here, Zinc Oxide (ZnO) nanostructures (NSs) were prepared via a green synthesis method based on garlic bulbs (Allium Sativum) extract (ZnO-Green), resulting in crystalline (wurtzite) nanorods (NRs). ZnO nanoparticles (NPs) were also chemically prepared through a standard co-precipitation (ZnO-Chem) for comparative solar photocatalytic (PC) studies. The green-synthesized ZnO NRs exhibited a favorable photocatalytic activity (PCA) in colloidal suspension for the methylene blue (MB) dye degradation upon exposure to concentrated sunlight. Comparison with the chemically synthesized ZnO results in almost equal degradations of 94% in optimal loading condition. To explore the possibility to use immobilized photocatalyst in heterogeneous condition, green-synthesized ZnO NRs coatings were fabricated and compared with a 135 nm thick ZnO thin film produced by pulsed laser deposition (PLD) (ZnO-PLD). PCA on MB degradation (120 min experiments) resulted in degradations of 69% and 73%, respectively, proving the feasibility of the immobilized photocatalyst approach. Finally, an economic analysis of the process shows that the combination of green-synthesis and concentrated sunlight significantly reduces costs, paving the way for large-scale photocatalytic wastewater remediation.
通过利用清洁、可再生且潜在低成本的资源，绿色合成材料和太阳能浓缩技术为高级氧化工艺（AOPs）在水修复领域提供了重要机会。在此，通过大蒜鳞茎（Allium Sativum）提取物（ZnO-Green）的绿色合成方法制备了氧化锌（ZnO）纳米结构（NSs），得到了结晶（纤锌矿）纳米棒（NRs）。还通过标准共沉淀法（ZnO-Chem）化学制备了氧化锌纳米颗粒（NPs），以进行比较太阳能光催化（PC）研究。在胶体悬浮液中，绿色合成的 ZnO NRs 在暴露于浓缩阳光时对亚甲基蓝（MB）染料的降解表现出良好的光催化活性（PCA）。与化学合成的 ZnO 相比，在最佳负载条件下几乎相等的降解率为 94%。为了探索在非均相条件下使用固定化光催化剂的可能性，制备了绿色合成 ZnO NRs 涂层，并与脉冲激光沉积（PLD）制备的 135nm 厚 ZnO 薄膜（ZnO-PLD）进行了比较。MB 降解的 PCA（120 分钟实验）分别导致 69%和 73%的降解，证明了固定化光催化剂方法的可行性。最后，对该工艺进行了经济分析，结果表明，绿色合成和浓缩阳光的结合显著降低了成本，为大规模光催化废水修复铺平了道路。
