Quantification of the dielectric constant of single non-spherical nanoparticles from polarization forces: eccentricity effects
| Autor: | Gabriel Gomila, Laura Fumagalli, Daniel Esteban-Ferrer |
|---|---|
| Rok vydání: | 2013 |
| Předmět: |
Materials science
Silicon dioxide Electrostatic force microscope Static Electricity Physics::Optics Nanoparticle Bioengineering Dielectric Molecular physics Condensed Matter::Materials Science chemistry.chemical_compound Optics General Materials Science Electrical and Electronic Engineering Aluminum oxide Microscopy business.industry Mechanical Engineering Electric Conductivity Numerical Analysis Computer-Assisted General Chemistry Polarization (waves) chemistry Mechanics of Materials Oblate spheroid Viruses Nanoparticles Polystyrene business |
| Zdroj: | Nanotechnology. 24(50) |
| ISSN: | 1361-6528 |
| Popis: | We analyze by means of finite-element numerical calculations the polarization force between a sharp conducting tip and a non-spherical uncharged dielectric nanoparticle with the objective of quantifying its dielectric constant from electrostatic force microscopy (EFM) measurements. We show that for an oblate spheroid nanoparticle of given height the strength of the polarization force acting on the tip depends linearly on the eccentricity, e, of the nanoparticle in the small eccentricity and low dielectric constant regimes (1e2 and 1ε(r)10), while for higher eccentricities (e2) the dependence is sub-linear and finally becomes independent of e for very large eccentricities (e30). These results imply that a precise account of the nanoparticle shape is required to quantify EFM data and obtain the dielectric constants of non-spherical dielectric nanoparticles. Experimental results obtained on polystyrene, silicon dioxide and aluminum oxide nanoparticles and on single viruses are used to illustrate the main findings. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|