Influence of Microwave Frequency and Power on Nanometal Growth
| Autor: | Jeffery R. Owens, Bridgett Ashley, Geoffrey F. Strouse, Christopher M. Dyer |
|---|---|
| Rok vydání: | 2018 |
| Předmět: |
Work (thermodynamics)
Materials science Nanoparticle 02 engineering and technology Dielectric 010402 general chemistry 021001 nanoscience & nanotechnology 01 natural sciences 0104 chemical sciences Surfaces Coatings and Films Electronic Optical and Magnetic Materials Power (physics) Reaction rate General Energy Nanocrystal Electric field Physical and Theoretical Chemistry Atomic physics 0210 nano-technology Microwave |
| Zdroj: | The Journal of Physical Chemistry C. 122:3617-3627 |
| ISSN: | 1932-7455 1932-7447 |
| DOI: | 10.1021/acs.jpcc.7b11366 |
| Popis: | The rapid heating rates (ΔT/δt) achieved in a microwave (MW) reactor has been shown to accelerate reaction rates due to the direct power absorbed (Pabs) into the reactants leading to faster kinetics. The Pabs is proportional to the dielectric cross section of the materials as defined by the real (e′) and imaginary (e″) components. In a nanocrystal, the dielectric cross-section will be frequency dependent as well as size dependent. In this work, the frequency dependent growth of nickel nanocrystals at frequencies of 2.45, 15.50, and 18.00 GHz at constant ΔT/δt was studied to evaluate the frequency dependence on MW growth of Ni. A scaling law behavior for growth rates is observed that is shown to depend on the MW electric field strength. A relationship is derived between the “configurational energy” of the precursor molecules and the final nanoparticle size. The study provides a clear description of a microwave effect that is dependent on the frequency and power of the microwave and offers further insight i... |
| Databáze: | OpenAIRE |
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