Nanotechnology National Laboratory for Agriculture (LNNA), Embrapa Instrumentação, Rua XV de Novembro, 1452, CP 741, São Carlos, SP, 13560-970, Brazil.
Department of Chemistry, Federal University of São Carlos, Via Washington Luiz, km 235, São Carlos, SP, 13565-905, Brazil.
Environ Sci Pollut Res Int. 2021 May;28(19):23731-23741. doi: 10.1007/s11356-020-11262-5. Epub 2020 Oct 23.
Nanotechnology has been studied on environmental remediation processes to foster greater photocatalysts efficiency and reuse in wastewater. This study investigated the photocatalytic efficiency and viability of niobium pentoxide (NbO) nanoparticles decorated with magnetic ferrite (cobalt ferrite (CoFeO) or magnesium ferrite (MgFeO)) for atrazine photodegradation. Thus, the decorated NbO was synthesized by the polymeric precursor method, forming nanoparticles with sizes ranging from 25 to 50 nm. Nanocomposite elementary analyses showed a homogeneous distribution of elements on all particles surface. Efficient magnetic saturation was observed for pure CoFeO (53 emu g) and MgFeO (19 emu g) nanoparticles, promoting the magnetic removal of NbO:CoFeO and NbO:MgFeO nanocomposites. Photocatalytic assays showed 88% efficiency for atrazine photodegradation with all nanomaterials, which represented a 21% increase compared to photolysis in the 1st cycle. The magnetic nanocomposites when applied to a 5th cycle maintained the atrazine photodegradation activity. In this way, magnetic NbO-based nanocomposites decorated with ferrite nanoparticles showed an efficient photocatalytic response, in addition to posterior magnetic removal from the aqueous medium. Therefore, the evaluated magnetic NbO nanocomposites may be an alternative to enhance the wastewater removal process and foster the reuse in advanced oxidative processes.
纳米技术已被应用于环境修复过程中，以提高光催化剂的效率并实现废水的再利用。本研究调查了五氧化二铌（NbO）纳米粒子负载磁性铁酸盐（钴铁氧体（CoFeO）或镁铁氧体（MgFeO））对莠去津光降解的光催化效率和可行性。因此，采用聚合物前驱体法合成了负载 NbO 的纳米粒子，形成了尺寸在 25 至 50nm 之间的纳米粒子。纳米复合材料的元素分析表明，所有粒子表面的元素分布均匀。纯 CoFeO（53 emu·g）和 MgFeO（19 emu·g）纳米粒子表现出高效的饱和磁化强度，有利于 NbO:CoFeO 和 NbO:MgFeO 纳米复合材料的磁性去除。光催化实验表明，所有纳米材料对莠去津的光降解效率达到 88%，与第一周期的光解相比提高了 21%。在第五个周期中，磁性纳米复合材料仍保持莠去津的光降解活性。因此，负载铁酸盐纳米粒子的磁性 NbO 基纳米复合材料表现出高效的光催化响应，同时可在后处理中从水相中磁性去除。因此，所评估的磁性 NbO 纳米复合材料可能是增强废水去除过程并促进在高级氧化过程中再利用的一种替代方法。
