College of Environmental Sciences and Engineering, Dalian Maritime University, Dalian 116026, China.
College of Ship and Ocean Engineering, Dalian Maritime University, Dalian 116026, China.
Talanta. 2018 May 1;181:352-358. doi: 10.1016/j.talanta.2018.01.023. Epub 2018 Jan 11.
Superparamagnetic FeO@FePO nanoparticles with core shell structure were prepared by coating iron phosphate on the surface of FeO nanoparticles by liquid phase deposition method. The prepared materials were characterized by vibrating sample magnetometer, scanning electron microscopy, X-ray diffractometer, Fourier transform infrared spectrometer, nano Zetasizer, X-ray photoelectron spectroscopy and Raman spectrometer. These characterization methods were also used to describe the adsorption mechanism. The obtained composite material was used for the adsorption of a heavy metal element, cadmium. Its unique magnetic properties are favorable for rapid separation and preconcentration of trace cadmium from aqueous solutions. About 100% sorption was achieved at pH 7 for 1mL, 10μgL of cadmium. Batch adsorption experiments show that the adsorption fits Langmuir model, and a maximum adsorption capacity 13.51mgg is derived for Cd(II). The retained Cd(II) could be readily recovered by 200μL of HNO (0.01molL). The cadmium in the eluate is quantified with detection by electrothermal atomic absorption spectrometry (ETAAS). A sample volume of 2000μL creates an enrichment factor of 10.3, along with a detection limit of 0.021µgL (3σ, n=7) and a RSD of 1.3% (0.1µgL, n=7) within a linear calibration range of 0.05-0.5µgL. The practical applicability of this procedure was validated by analyzing cadmium contents in a certified reference material (GBW08608) and two environmental water samples.
具有核壳结构的超顺磁 FeO@FePO 纳米粒子是通过液相沉积法在 FeO 纳米粒子表面包覆磷酸铁制备的。采用振动样品磁强计、扫描电子显微镜、X 射线衍射仪、傅里叶变换红外光谱仪、纳米 Zetasizer、X 射线光电子能谱仪和拉曼光谱仪对所制备的材料进行了表征。这些表征方法也用于描述吸附机制。所得复合材料用于吸附重金属元素镉。其独特的磁性有利于从水溶液中快速分离和预浓缩痕量镉。在 pH 为 7、镉浓度为 10μgL 的 1mL 溶液中，吸附率达到约 100%。批量吸附实验表明，吸附符合 Langmuir 模型，得出 Cd(II)的最大吸附容量为 13.51mgg。通过 200μL 的 HNO（0.01molL）可容易地回收保留的 Cd(II)。采用电热原子吸收光谱法（ETAAS）对洗脱液中的镉进行定量检测。2000μL 的样品体积可产生 10.3 的富集因子，线性校准范围内 0.05-0.5μgL 的检测限为 0.021µgL（3σ，n=7），相对标准偏差为 1.3%（0.1µgL，n=7）。通过分析认证参考物质（GBW08608）和两个环境水样中的镉含量验证了该方法的实际适用性。
