Nanoparticle Synthesis and Growth in a Continuous Plasma Reactor from Organosilicon Precursors

Abstract

Silica-like nanoparticles are produced from four different organosilicon monomers HMDSO, TMDSO, TEOS and TMOS in a continuous non-equilibrium plasma reactor. The nanoparticle synthesis is studied as a function of the process pressure, plasma power, gas velocity,and gas composition (Ar:O 2 :monomer). The morphology, mass production,and chemical composition of the plasma formed particlesare investigated. An adapted particle growth model for a continuous plasma reactor is introduced which explains the influence of the different process parameters on particle evolution. The morphology of the produced amorphous particles is similar to fumed silica, with primary particles in the size range of 10 nm building hard-agglomerates of several hundred nanometers during the synthesis.

Substrate geometry modulates self-assembly and collection of plasma polymerized nanoparticles

“…5) suggests that interparticle electrostatic repulsion is no longer effective in preventing particle-particle aggregation inside these wells. The formation of dust particulate aggregates has been previously reported in the afterglow region of a downstream plasma reactor in silane-based discharges 12 , suggesting here that the plasma is unable to expand throughout the entire depth of the 24-and 48-well plates (Fig. 7b).…”

“…The plasma reactive environment activates monomers into building blocks that polymerize and diffuse toward the plasma boundaries, resulting in the deposition of thin films with modulated properties, i.e., surface polymerization. A far less explored, often avoided, domain of reactive PP is manifested in some hydrocarbons 9 , fluorocarbons 10 , or silanes 11,12 discharges, where surface polymerization occurs simultaneously with plasma bulk polymerization, i.e., dusty plasmas [13][14][15] . Ionization of acetylene in the plasma for instance, triggers a continuous formation of carbonaceous nanoclusters that aggregate to form charged particulates in the plasma volume.…”

“…Thermoelectric Peltier elements 27 may also be used to increase the thermophoretic force and drive dust particles towards surfaces in a reactor. The synthesis and collection of silicon-based, non-spherical particles at high mass rates (~2 g/h) has been also demonstrated from organosilicon precursors in continuous downstream plasma reactor configurations 12 . However, most collection strategies were not developed envisaging the use of plasma dust for nanomedicine and are usually characterized by low nanoparticle yield, size polydispersity or irreversible aggregation.…”

Plasma Enhanced CVD of Organosilicon Thin Films on Electrospun Polymer Nanofibers

“…It is assumed that the nanostructure of multi‐jet films is also related to formation of clusters and nanoparticles in the gas phase and their incorporation into the growing film. The formation of nanoparticles with a size distribution varying from 10 to 500 nm was already found before for silane, vinyltrimethoxy silane, and HMDSO plasmas both at LP and AP . The nucleation and growth of these nanoparticles depend on the electrical properties of the discharge, plasma chemistry, and gas dynamics, as numerical simulation revealed .…”

One‐Step Fabrication of Nanocomposite Thin Films of PTFE in SiOx for Repelling Water

“…PECVD, referred to herein as plasma polymerization, is one deposition process that allows such control over the organic or inorganic nature of the resulting film by modification of parameters such as monomer flow, plasma temperature, and/or oxygen concentration in the plasma . Such methodology has been previously demonstrated for plasma‐assisted synthesis of nanoparticles and superhydrophobic coatings . In practice, to achieve strongly hydrophobic and superhydrophobic surfaces, a high level of surface roughness is required in addition to the appropriate chemical functionality .…”