Effects of grain size and thermodynamic energy on the lattice parameters of metallic nanomaterials

• We developed a method to study the lattice distortion rates (Δa/a) of nanomaterials.
• Δa/a follows an inverse proportional relationship with the size.
• The surface tension and Young’s modulus exhibit a linear relationship for some nanometals.
• Δa/a was calculated for nanoparticles, nanowires, and nanofilms.

A thermodynamic method based on surface thermodynamics and atomic bond energy was developed to accurately investigate the lattice distortion rates of metallic nanomaterials. The results indicated that the lattice distortion rates of nanomaterials follow an inverse proportional relationship with the size, in good agreement with the experimental results. In this method, the anisotropy of the lattice distortion was a considerable issue. We found that the surface tension and Young’s modulus of the nanocrystals, compared with those of the bulk materials, change because of the lattice distortion and exhibit a linear relationship at the nanoscale. By defining a shape factor (ξ), the lattice distortion rates of nanoparticles, nanowires, and nanofilms were calculated. This method provides a new approach for the evaluation of the lattice distortion rates in nanomaterials.

Variation of the lattice distortion rates (Δa/a) with the size for nanoparticles.Figure optionsDownload as PowerPoint slide