Aerosol generation by spark discharge

doi:10.1016/0021-8502(88)90215-7

Journal of Aerosol Science

Volume 19, Issue 5, October 1988, Pages 639-642

https://doi.org/10.1016/0021-8502(88)90215-7 Get rights and content

Abstract

An aerosol generator producing particles of any desired mobility equivalent radius, and conducting material has been developed. Particles are formed by electrode atomization in a spark discharge. A high yield of charged particles enables generation of high concentration (> 10⁵cm⁻³) monodisperse aerosols using electrostatic classification. In order to obtain non-agglomerated particles, the aerosol can be turbulently diluted at the region of particle formation by gas injection through a nozzle. Charged gold particles in the atomic cluster size range (1.3 nm) have been produced in a concentration of 3 × 10⁵cm⁻³.

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Segregated bimetallic nanoparticles like core-shell nanoparticles are of interest in various fields including biomedicine, catalysis, and optoelectronics. Aerosol technology is an optimal platform to control nanoparticle size, structure, and composition, which are some of the most important parameters tuning the material performance for the intended applications. Here, we develop a novel evaporator design to coat core particles on-line with a shell directly in the gas phase. The evaporator employs a local heater that decouples heating the evaporating material from the aerosol particles to limit core-shell alloying. We characterize the system by evaporating Zn onto core particles of Au, Sn, and Bi and demonstrate the core-shell particle formation with controllable shell thickness in each material system. We discuss simple models to explain the observed growth process inside the evaporator and the resulting shell formation.
Effect of the carrier gas on the structure and composition of Co–Ni bimetallic nanoparticles generated by spark ablation
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Spark discharge generator as a stable and reliable nanoparticle synthesis device: Analysis of the impact of process and circuit variables on the characteristics of synthesized nanoparticles
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Technical noteAerosol generation by spark discharge

Abstract

J. Aerosol Sci.

J. Aerosol Sci.

Enormous Enhancement of van der Waals Forces between small silver particles

Phys. Rev. Lett.

Technical note
Aerosol generation by spark discharge