It is widely known that the existence of arsenic (As) in water negatively affects humans and the environment. We report the synthesis, characterization, and application of boron nitride nanosheets (BNNSs) and Fe₃O₄-functionalized BNNS (BNNS–Fe₃O₄) nanocomposite for removal of As(V) ions from aqueous systems. The morphology, surface properties, and compositions of synthesized nanomaterials were examined using scanning electron microscopy, transmission electron microscopy, X-ray powder diffraction, surface area analysis, zero-point charge, and magnetic moment determination. The BNNS–Fe₃O₄ nanocomposites have a specific surface area of 119 m² g^–1 and a high saturation magnetization of 49.19 emu g^–1. Due to this strong magnetic property at room temperature, BNNS–Fe₃O₄ can be easily separated in solution by applying an external magnetic field. From the activation energies, it was found that the adsorption of As(V) ions on BNNSs and BNNS–Fe₃O₄ was due to physical and chemical adsorption, respectively. The maximum adsorption capacity of BNNS–Fe₃O₄ nanocomposite for As(V) ions has been found to be 26.3 mg g^–1, which is 5 times higher than that of unmodified BNNSs (5.3 mg g^–1). This closely matches density functional theory simulations, where it is found that binding energies between BNNS–Fe₃O₄ nanocomposite and As(OH)₅ are 5 times higher than those between BNNSs and As(OH)₅, implying 5 times higher adsorption capacity of BNNS–Fe₃O₄ nanocomposite than unmodified BNNSs. More importantly, it was observed that the synthesized BNNS–Fe₃O₄ nanocomposite could reduce As(V) ion concentration from 856 ppb in a solution to below 10 ppb (>98.83% removal), which is the permissible limit according to World Health Organization recommendations. Finally, the synthesized adsorbent showed both separation and regeneration properties. These findings demonstrate the potential of BNNS–Fe₃O₄ nanocomposite for commercial application in separation of As(V) ions from potable and waste water streams.

中文翻译：

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磁铁矿涂覆的氮化硼纳米片用于去除水中的砷（V）

众所周知，水中砷的存在会对人类和环境产生负面影响。我们报告了氮化硼纳米片（BNNSs）和Fe ₃ O ₄官能化的BNNS（BNNS–Fe ₃ O ₄）纳米复合材料的合成，表征和应用，用于从水系统中去除As（V）离子。使用扫描电子显微镜，透射电子显微镜，X射线粉末衍射，表面积分析，零点电荷和磁矩测定来检查合成纳米材料的形态，表面性质和组成。BNNS–Fe ₃ O ₄纳米复合材料的比表面积为119 m ² g ^–1和49.19 emu g ^–1的高饱和磁化强度。由于在室温下具有很强的磁性，因此通过施加外部磁场可以很容易地将BNNS–Fe ₃ O ₄分离成溶液。从活化能中发现，As（V）离子在BNNSs和BNNS–Fe ₃ O _4上的吸附分别是由于物理和化学吸附。已发现BNNS–Fe ₃ O ₄纳米复合材料对As（V）离子的最大吸附容量为26.3 mg g ^–1，这是未修饰的BNNSs（5.3 mg g ^–1）的5倍。）。这与密度泛函理论模拟非常吻合，在该模拟中，发现BNNS–Fe ₃ O ₄纳米复合材料与As（OH）₅之间的结合能比BNNSs与As（OH）₅之间的结合能高5倍，这意味着吸附能力高5倍。 BNNS–Fe ₃ O ₄纳米复合材料的含量比未修饰的BNNSs高。更重要的是，观察到合成的BNNS–Fe ₃ O ₄纳米复合材料可以将As（V）离子浓度从溶液中的856 ppb降低到10 ppb以下（去除率> 98.83％），这是根据世界卫生组织的建议所允许的极限。最后，合成的吸附剂同时显示了分离和再生特性。这些发现证明了BNNS–Fe ₃ O ₄纳米复合材料在从饮用水和废水流中分离As（V）离子的商业应用潜力。