Materials | |
Precursor-Less Coating of Nanoparticles in the Gas Phase | |
Tobias V. Pfeiffer1  Puneet Kedia1  Maria E. Messing2  Mario Valvo3  Andreas Schmidt-Ott1  | |
[1] Faculty of Applied Sciences, Delft University of Technology, Julianalaan 136, Delft 2628 BL, The |
|
关键词: spark ablation; nanoparticles; coating; gas phase; continuous process; | |
DOI : 10.3390/ma8031027 | |
来源: mdpi | |
【 摘 要 】
This article introduces a continuous, gas-phase method for depositing thin metallic coatings onto (nano)particles using a type of physical vapor deposition (PVD) at ambient pressure and temperature. An aerosol of core particles is mixed with a metal vapor cloud formed by spark ablation by passing the aerosol through the spark zone using a hollow electrode configuration. The mixing process rapidly quenches the vapor, which condenses onto the core particles at a timescale of several tens of milliseconds in a manner that can be modeled as bimodal coagulation. Gold was deposited onto core nanoparticles consisting of silver or polystyrene latex, and silver was deposited onto gold nanoparticles. The coating morphology depends on the relative surface energies of the core and coating materials, similar to the growth mechanisms known for thin films: a coating made of a substance having a high surface energy typically results in a patchy coverage, while a coating material with a low surface energy will normally “wet” the surface of a core particle. The coated particles remain gas-borne, allowing further processing.
【 授权许可】
CC BY
© 2015 by the authors; licensee MDPI, Basel, Switzerland
【 预 览 】
Files | Size | Format | View |
---|---|---|---|
RO202003190015424ZK.pdf | 7795KB | download |