Impact Fragmentation of Metal Nanoparticle Agglomerates
Impact Fragmentation of Metal Nanoparticle Agglomerates
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金属纳米颗粒团聚体的冲击破碎
DOI：
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发表时间：
2007
期刊：
影响因子：
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通讯作者：
A. Weber
中科院分区：
文献类型：
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作者：
M. Seipenbusch;P. Toneva;W. Peukert;A. Weber
用Ni和Pt的纳米颗粒的聚集体进行解聚集实验。通过在单级低压冲击器中高速冲击团聚体来诱导破碎，并通过TEM分析来评价破碎模式。威布尔统计用于定量描述的碎裂行为。本研究表明，对于明确定义的颗粒间接触，冲击破碎技术与根据Weibull统计的评价相结合，可以恢复预期的尺寸依赖性。对于Pt和Ag，粘附力颗粒尺寸依赖性由货车范德华力主导。与此相反，在12-28 nm的尺寸范围内的Ni颗粒之间的粘附力显示出更强的增加与颗粒尺寸。这种现象可能归因于永磁偶极矩，其也反映在团聚体的链状形状中。对于接触不太明确的纳米颗粒团聚体，例如工业环境中的纳米颗粒团聚体，该方法提供了一个有前途的应用，以揭示纳米颗粒粉末的粘结强度和内聚性。
Deagglomeration experiments were performed with agglomerates of nanoparticles of Ni and Pt. The fragmentation was induced by high velocity impaction of the agglomerates in a single‐stage low pressure impactor and the fragmentation patterns were evaluated by TEM analysis. Weibull statistics are employed for a quantitative description of the fragmentation behavior. This study shows that for well‐defined interparticle contacts, the impact fragmentation technique combined with the evaluation according to Weibull statistics, allows the recovery of the expected size dependencies. For Pt and Ag, the adhesion force particle size dependency was dominated by van der Waals forces. In contrast, the adhesion force between Ni particles in the size range from 12–28 nm revealed a much stronger increase with particle size. This phenomenon may be attributed to permanent magnetic dipole moments which are also reflected in the chain‐like shape of the agglomerates. For nanoparticle agglomerates with less well‐defined contacts, such as those in industrial environments, the method provides a promising application to reveal the bond strength and cohesiveness of nanoparticle powders.