Zammit Ian, Vaiano Vincenzo, Iervolino Giuseppina, Rizzo Luigi
Department of Civil Engineering, University of Salerno Via Giovanni Paolo II 132, 84084 Fisciano SA Italy
Department of Industrial Engineering, University of Salerno Via Giovanni Paolo II 132, 84084 Fisciano SA Italy.
RSC Adv. 2018 Jul 20;8(46):26124-26132. doi: 10.1039/c8ra05020a. eCollection 2018 Jul 19.
Heterogeneous photocatalysis (HPC) is a subset of Advanced Oxidation Processes (AOPs) with potential future applications in water disinfection. Herein, a zinc oxide photocatalyst was doped with cerium at various atomic ratios ranging from 0 to 0.1 Ce : Zn. Keeping in mind that the application of HPC is often limited by its cost of use, a simple and easy to upscale method, that is the hydroxide induced hydrolysis of zinc nitrate in the presence of Ce followed by calcination at 300 °C, was used to synthesise the catalysts. The catalysts have been characterized by different techniques such as X-ray diffraction (XRD), UV-vis diffuse reflectance (UV-vis DRS) and Raman spectroscopy. XRD results showed that Ce ions were successfully incorporated into the ZnO lattice. UV-vis DRS spectra evidenced that Ce-ZnO samples present band-gap values of about 2.97 eV, lower than those of undoped ZnO (3.21 eV). These various photocatalysts, at 0.1 g L in saline 0.85%, were used to inactivate previously isolated from an urban wastewater treatment plant. Higher atomic ratios of Ce in the ZnO lattice, as confirmed by XRD and Raman spectroscopy, showed significant improvements to the inactivation rate; the resulting recommended optimum cerium loading of 0.04 : 1 Ce : Zn gave multiple orders of magnitude higher rate of inactivation after 60 min of treatment when compared to un-doped ZnO. This optimum loading of cerium was faster than the de facto literature standard TiO-P25 tested under identical conditions.
多相光催化（HPC）是高级氧化工艺（AOPs）的一个子集，在水消毒方面具有潜在的未来应用前景。在此，氧化锌光催化剂以0至0.1的铈与锌原子比进行掺杂。考虑到HPC的应用常常受到其使用成本的限制，采用了一种简单且易于扩大规模的方法，即在铈存在的情况下，通过氢氧化锌诱导硝酸锌水解，然后在300℃下煅烧来合成催化剂。这些催化剂通过X射线衍射（XRD）、紫外可见漫反射（UV-vis DRS）和拉曼光谱等不同技术进行了表征。XRD结果表明铈离子成功掺入到ZnO晶格中。UV-vis DRS光谱证明Ce-ZnO样品的带隙值约为2.97 eV，低于未掺杂的ZnO（3.21 eV）。这些各种光催化剂，在0.85%的盐水中浓度为0.1 g/L，用于灭活先前从城市污水处理厂分离出的[具体物质未给出]。XRD和拉曼光谱证实，ZnO晶格中较高的铈原子比显示出对灭活率有显著提高；与未掺杂的ZnO相比，最终推荐的最佳铈负载量为0.04:1的Ce:Zn，在处理60分钟后灭活率提高了多个数量级。这种铈的最佳负载量比在相同条件下测试的实际文献标准TiO-P25更快。
