Precursor-Less Coating of Nanoparticles in the Gas Phase

Precursor-Less Coating of Nanoparticles in the Gas Phase

Pfeiffer, T.V.
Kedia, P.
Messing, M.E.
Valvo, M.
Schmidt-Ott, A.

Applied Sciences

ChemE/Chemical Engineering

2015-03-11

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.

spark ablation
nanoparticles
coating
gas phase
continuous process
OA-Fund TU Delft

http://resolver.tudelft.nl/uuid:e8972031-94a7-4fd2-bdd0-5defcce3010b

https://doi.org/10.3390/ma8031027

MDPI

1996-1944

Materials, 8 (3), 2015

Institutional Repository

journal article

(c) 2015 The Author(s)
This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution license (http://creativecommons.org/licenses/by/3.0/)