Laboratory of Physics of Materials and Nanomaterials Applied at Environment (LaPhyMNE), Faculty of Sciences, University of Gabes, Erriadh Manara Zrig, 6072 Gabes, Tunisia.
Thin Films and Nanostructures Electrodeposition Group (GE-CPN), Department of Materials Science and Physical Chemistry, University of Barcelona, Martí i Franquès 1, E-08028 Barcelona, Spain.
Toxins (Basel). 2021 Jan 17;13(1):66. doi: 10.3390/toxins13010066.
The ZnO-based visible-LED photocatalytic degradation and mineralization of two typical cyanotoxins, microcystin-LR (MC-LR), and anatoxin-A were examined. Al-doped ZnO nanoparticle photocatalysts, in Al:Zn ratios between 0 and 5 at.%, were prepared via sol-gel method and exhaustively characterized by X-ray diffraction, transmission electron microscopy, UV-vis diffuse reflectance spectroscopy, photoluminescence spectroscopy, and nitrogen adsorption-desorption isotherms. With both cyanotoxins, increasing the Al content enhances the degradation kinetics, hence the use of nanoparticles with 5 at.% Al content (A5ZO). The dosage affected both cyanotoxins similarly, and the photocatalytic degradation kinetics improved with photocatalyst concentrations between 0.5 and 1.0 g L. Nevertheless, the pH study revealed that the chemical state of a species decisively facilitates the mutual interaction of cyanotoxin and photocatalysts. A5ZO nanoparticles achieved better outcomes than other photocatalysts to date, and after 180 min, the mineralization of anatoxin-A was virtually complete in weak alkaline medium, whereas only 45% of MC-LR was in neutral conditions. Moreover, photocatalyst reusability is clear for anatoxin-A, but it is adversely affected for MC-LR.
研究了基于 ZnO 的可见光-LED 光催化降解和两种典型的蓝藻毒素（微囊藻毒素-LR（MC-LR）和鱼腥藻毒素-A）的矿化。通过溶胶-凝胶法制备了 Al 掺杂 ZnO 纳米粒子光催化剂，Al:Zn 比为 0 至 5 at.%，并通过 X 射线衍射、透射电子显微镜、紫外-可见漫反射光谱、光致发光光谱和氮吸附-脱附等温线进行了详尽的表征。对于这两种蓝藻毒素，增加 Al 含量都会增强降解动力学，因此使用 Al 含量为 5 at.%的纳米颗粒（A5ZO）。两种蓝藻毒素的剂量影响相似，光催化剂浓度在 0.5 和 1.0 g/L 之间时，光催化降解动力学得到改善。然而，pH 值研究表明，物种的化学状态会显著促进蓝藻毒素与光催化剂的相互作用。A5ZO 纳米粒子比迄今为止的其他光催化剂取得了更好的效果，在 180 分钟后，在弱碱性介质中鱼腥藻毒素-A 的矿化几乎完全，而在中性条件下只有 45%的微囊藻毒素-LR 被矿化。此外，光催化剂对鱼腥藻毒素-A 的可重复使用性很明显，但对微囊藻毒素-LR 的可重复使用性则受到不利影响。
