摘要
The development of methods to produce nanoparticles with unique properties via the aerosol route is progressing rapidly. Typical characterization techniques extract particles from the synthesis process for subsequent offiine analysis, which may alter the particle characteristics. In this work, we use laser-vaporization aerosol mass spectrometry （LV-AMS） with 70-eV electron ionization for real-time, in-situ nanoparticle characterization. The particle characteristics are examined for various aerosol synthesis methods, degrees of sintering, and for controlled condensation of organic material to simulate surface coating/functionalization. The LV-AMS is used to characterize several types of metal nanoparticles （Ag, Au, Pd, PdAg, Fe, Ni, and Cu）. The degree of oxidation of the Fe and Ni nanoparticles is found to increase with increased sintering temperature, while the surface organic-impurity content of the metal particles decreases with increased sintering temperature. For aggregate metal particles, the organic-impurity content is found to be similar to that of a monolayer. By comparing different equivalent-diameter measurements, we demonstrate that the LV-AMS can be used in tandem with a differential mobility analyzer to determine the compactness of synthesized metal particles, both during sintering and during material addition for surface functionalization. Further, materials supplied to the particle production line downstream of the particle generators are found to reach the generators as contaminants. The capacity for such in-situ observations is important, as it facilitates rapid response to undesired behavior within the particle production process. This study demonstrates the utility of real-time, in-situ aerosol mass spectrometric measurements to characterize metal nanoparticles obtained directly from the synthesis process line, including their chemical composition, shape, and contamination, providing the potential for effective optimization of process operating parameters.
方法的发展很快正在进行经由喷雾器线路与唯一的性质生产 nanoparticles。典型描述技术为随后的离线的分析从合成过程提取粒子，它可以改变粒子特征。在这个工作，我们与 70-eV 电子电离使用激光蒸发喷雾器团 spectrometry (LVbe ) 为即时，在原处 nanoparticle 描述。粒子特征为各种各样的喷雾器合成方法被检验， sintering 的度，并且为器官的材料到的控制冷凝作用模仿表面 coating/functionalization。LVbe 被用来描绘金属 nanoparticles (Ag， Au， Pd， PdAg， Fe， Ni，和 Cu ) 的几种类型。Fe 和 Ni nanoparticles 的氧化的度被发现与增加的 sintering 温度增加，当时表面金属粒子的器官杂质的内容与增加的 sintering 温度减少。为总数金属粒子，器官杂质的内容被发现类似于单层的。由比较不同相等直径的大小，我们证明 LVbe 能与一个微分活动性分析器一起被使用决定综合金属粒子的紧密，在 sintering 期间并且在为表面 functionalization 的材料增加期间。进一步，供应到粒子生产的材料发电机被发现作为沾染物到达发电机的粒子下游地排队。为这的能力在原处观察是重要的，当它在粒子生产以内便于快速的反应到不希望得到的行为，处理。这研究表明实用程序即时，在原处描绘从合成进程直接获得的金属 nanoparticles 的度谱的大小衬里包括他们的化学作文，形状，和污染，为进程操作的有效优化提供潜力的喷雾器质量参数。
