Abstract Mercury is a specific concern worldwide because of its high toxicity. Exposure to mercury, even at very low concentrations, induces digestive, brain, kidney, neurological and endocrine system diseases. In this work, Fe2O3 nanoparticles were synthesized via one step solution combustion synthesis using glycine as a fuel. The structural features of the as formed Fe2O3 nanoparticles were characterized by XRD, SEM, EDX and FTIR. Further, the surface of the prepared Fe2O3 nanoparticles were coated with silica groups followed by thiol(-SH)functionalization using l -cysteine by ultra-sonication technique. The surface functionalized magnetic nanoparticles were analyzed by FT-IR technique, to confirm the –SH functionalization. The functionalized magnetic nanoparticles of various amounts (0.005 g, 0.010 g. 0.015 g, 0.020 g) were used for removal of Hg2+ ion in 50 ppm aqueous solution. After the adsorption process is over, the Fe2O3@SiO2@SH nanoparticles extracted using strong magnet and the resultant Hg2+ ion in water is studied by complexing with dithizone ligand using UV visible spectroscopic technique. The disappearance of absorbance peak corresponds to [Hg(dithizone)2]2+ at 490 nm, for 50 ppm Hg2+ ion solution when 10 mg of the Fe2O3@SiO2@SH nanoparticles used, confirms that about 98% Hg2+ ion in water is removed.

中文翻译：

---

表面功能化磁性 α-Fe2O3 纳米粒子：合成、表征和水中 Hg2+ 离子去除

摘要 汞因其高毒性而在世界范围内受到特别关注。接触汞，即使浓度非常低，也会诱发消化、脑、肾、神经和内分泌系统疾病。在这项工作中，使用甘氨酸作为燃料，通过一步溶液燃烧合成法合成了 Fe2O3 纳米颗粒。通过XRD、SEM、EDX和FTIR表征形成的Fe2O3纳米颗粒的结构特征。此外，制备的 Fe2O3 纳米粒子的表面涂有二氧化硅基团，然后通过超声技术使用 l-半胱氨酸进行硫醇 (-SH) 功能化。通过 FT-IR 技术分析表面功能化的磁性纳米粒子，以确认 -SH 功能化。各种量的官能化磁性纳米粒子（0.005 g、0.010 g、0.015 g、0. 020 g) 用于去除 50 ppm 水溶液中的 Hg2+ 离子。吸附过程结束后，利用紫外可见光谱技术，通过与双硫腙配体络合，研究了强磁铁提取的 Fe2O3@SiO2@SH 纳米粒子和水中生成的 Hg2+ 离子。吸收峰的消失对应于 490 nm 处的 [Hg(双硫腙)2]2+，对于 50 ppm Hg2+ 离子溶液，当使用 10 mg Fe2O3@SiO2@SH 纳米粒子时，证实水中约 98% 的 Hg2+ 离子被去除.