Design-Oriented Modelling of Different Quenching Solutions in Induction Plasma Synthesis of Copper Nanoparticles

Abstract

The aim of this paper is to compare the effects of different mechanisms underlying the synthesis of copper nanoparticles using an atmospheric pressure radiofrequency induction thermal plasma. A design oriented modelling approach was used to parametrically investigate trends and impact of different parameters on the synthesis process through a thermo-fluid dynamic model coupled with electromagnetic field equations for describing the plasma behaviour and a moment method for describing nanoparticles nucleation, growth and transport. The effect of radiative losses from Cu vapour on the precursor evaporation efficiency is highlighted, with occurrence of loading effect even with low precursor feed rate due to the decrease in plasma temperature. A method to model nanoparticle deposition on a porous wall is proposed, in which a sticking coefficient is employed to model particle sticking on the porous wall used to carry a quench gas flow into the chamber. Two different reaction chamber designs combined with different quench gas injection strategies (injection through a porous wall for "active" quenching; injection of a shroud gas for "passive" quenching) are analysed in terms of process yield and size distribution of the synthetized nanoparticles. Conclusion can be drawn on the characteristics of each quenching strategy in terms of throughput and mean diameter of the synthesized nanoparticles.

Mini Review on Gas-Phase Synthesis for Energy Nanomaterials

“…Fox et al has developed Reynolds-averaged Navier–Stokes, large-eddy simulation, and direct numerical simulation (DNS) techniques to model the nanoparticles generated in turbulent flame reactors. ,, Since vortices at different scales in turbulent flows influence the aerosol dynamics of coagulation, convention, diffusion, and even nucleation, the physical understanding of aerosol-turbulence interactions as well as the use of appropriate models are key factors to simulate aerosol dynamics accurately in turbulent flows. Apart from the flame reactor, the method of moments with simulated local flow and temperature fields are employed to model a CVD reactor, a laminar flow aerosol reactor, a wall-heated aerosol reactor, , a laser-driven reactor, and a plasma synthesis reactor …”

“…Apart from the flame reactor, the method of moments with simulated local flow and temperature fields are employed to model a CVD reactor, 158 a laminar flow aerosol reactor, 159 a wall-heated aerosol reactor, 160,161 a laser-driven reactor, 162 and a plasma synthesis reactor. 163 Under a Lagrangian framework, the simulation of particles' motion and the aerosol dynamics modeling are decoupled. Particles are divided into different parcels, which are shown in Figure 12.…”

3D modelling of the synthesis of copper nanoparticles by means of a DC transferred arc twin torch plasma system

“…The governing equations and assumptions for plasma thermo-fluid-dynamics calculations are described in [13]. The equations have been properly implemented in a3D environment, moreover, not only the effect of Cu vapour on radiative losses of the gas mixture, but also on the transport and thermodynamic properties is considered.…”

“…The evaporation efficiency is also limited by the radiative power loss coming from the vapour present in the plasma. Most metal vapours have high emissivity and significantly reduce the precursor evaporation efficiency [12][13][14]. Quench gas injection is perhaps the optimization parameter most thoroughly investigated, because it impacts strongly on flow fields, temperature distribution and cooling rates in the system [15][16][17][18].…”

Surfactant-free synthesis of copper nanoparticles and gas phase integration in CNT-composite materials

“…Several physical methods have been therefore used for producing Cu-NPs. 19,20 Plasmas operated at atmospheric pressure have been also used for this purpose presenting some benefits compared to other methods. Xu Zhijian et al have investigated the use of dielectric barrier discharges fed with hydrogen (H 2 ) to reduce copper oxide and obtain Cu-NPs (~35 nm in diameter).…”