Nanda K K, Maisels A, Kruis F E, Fissan H, Stappert S
Department of Electrical Engineering and Information Technology, University Duisburg-Essen, 47048 Duisburg, Germany.
Phys Rev Lett. 2003 Sep 5;91(10):106102. doi: 10.1103/PhysRevLett.91.106102. Epub 2003 Sep 4.
We present an accurate online method for the study of size-dependent evaporation of free nanoparticles allowing us to detect a size change of 0.1 nm. This method is applied to Ag nanoparticles. The linear relation between the onset temperature of evaporation and the inverse of the particle size verifies the Kelvin effect and predicts a surface energy of 7.2 J/m(2) for free Ag nanoparticles. The surface energy of nanoparticles is significantly higher as compared to that of the bulk and is essential for processes such as melting, coalescence, evaporation, growth, etc., of nanoparticles.
我们提出了一种精确的在线方法，用于研究自由纳米颗粒的尺寸依赖性蒸发，该方法能够检测到0.1纳米的尺寸变化。此方法应用于银纳米颗粒。蒸发起始温度与颗粒尺寸倒数之间的线性关系验证了开尔文效应，并预测自由银纳米颗粒的表面能为7.2焦耳每平方米。与块体材料相比，纳米颗粒的表面能显著更高，并且对于纳米颗粒的诸如熔化、聚结、蒸发、生长等过程至关重要。
