Single-phase Ag2Al intermetallic nanoparticles, and Ag and Al metallic nanoparticles were synthesized by the flow-levitation （FL） method. Measurements of d-spacings from X-ray diffraction and electron diffraction co...Single-phase Ag2Al intermetallic nanoparticles, and Ag and Al metallic nanoparticles were synthesized by the flow-levitation （FL） method. Measurements of d-spacings from X-ray diffraction and electron diffraction confirmed that the intermetallic nanoparticles had the hexagonal Ag2Al structure. The morphology, crystal structure and chemical composition of Ag2Al nanoparticles were investigated by transmission electron microscopy, X-ray diffraction and induction-coupled plasma spectroscopy. A thin amorphous coating was formed around the particles when exposed to air. Based on the XPS measurements, the surface coating of the Ag2Al nanoparticles could most likely be aluminum oxide or silver aluminum oxide. Therefore, the single-phase nanocrystalline Ag2Al intermetallic compound particles can be produced by adjusting some experimental parameters in FL method.展开更多
文摘为了实现激光诱导击穿光谱(LIBS)技术对自然水体中痕量铬(Cr)元素的快速检测,实验以蒙脱石为吸附基底,对溶液中的Cr元素富集后进行LIBS测量。通过分析样品的发射光谱特性,确定了425.4 nm的特征谱线为Cr的分析线;并基于不同参数条件下分析线的强度和信噪比,得出最佳激光光斑尺寸为50μm,最优的激光能量为40.8 m J,最佳延迟时间为5μs。在最佳实验参数条件下,建立了水体中Cr元素的定标曲线,拟合结果显示,线性相关系数为0.989,检测限达到0.33 mg/L。研究结果为水体中重金属元素的LIBS测量提供了一种新途径。
基金Project (10804101) supported by the National Natural Science Foundation of China
文摘Single-phase Ag2Al intermetallic nanoparticles, and Ag and Al metallic nanoparticles were synthesized by the flow-levitation （FL） method. Measurements of d-spacings from X-ray diffraction and electron diffraction confirmed that the intermetallic nanoparticles had the hexagonal Ag2Al structure. The morphology, crystal structure and chemical composition of Ag2Al nanoparticles were investigated by transmission electron microscopy, X-ray diffraction and induction-coupled plasma spectroscopy. A thin amorphous coating was formed around the particles when exposed to air. Based on the XPS measurements, the surface coating of the Ag2Al nanoparticles could most likely be aluminum oxide or silver aluminum oxide. Therefore, the single-phase nanocrystalline Ag2Al intermetallic compound particles can be produced by adjusting some experimental parameters in FL method.
