Page 65 - Synthesis of Functional Nanoparticles Using an Atmospheric Pressure Microplasma Process - LiangLiang Lin
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Iron Oxide Nanoparticles Synthesis and Mechanism Study - a Proof-of-Concept Model Study
K at 1.05 W and 1100 K at 2.27 W. Table 3.3 summarizes the main experiment data for two setting of power dissipated in micro discharge.
Table 3.3 Summary of the main experiment data at two plasma powers
      Power Voltage (W) (V) 1.05 172 2.27 177
Current (mA) 6.134 12.83
Gas temperature (K)
900
1100
           Figure 3.11 Experimental spectra and the corresponding SPECAIR simulation of microplasma containing 98.5 ppm ferrocene vapor, operated at plasma power of (a) 1.05 W and (b) 2.27 W
The diagnostics and modeling of the intrinsic plasma parameters such as electron concentration and mean electron energy are out of the scope of present investigation. Moreover, to our knowledge, the cross-sections of the electron impact processes for FeCp2, necessary for consistent analysis, were not reported in the literature. Nevertheless, given low partial concentration of the ferrocene admixture studied in present work and its negligible effect on the measured electrical characteristics it can be assumed that plasma properties are close to the discharge in pure argon. The value of the reduced electric field E/N of 4.1 Td for the positive column of atmospheric pressure micro-discharge in argon can be derived from the electric field and gas temperature data presented in Ref. [35]. By using the reduced electric field value as an input parameter for Bolsig+ electron kinetics solver,36,37 and taking into account e-e collisions and expected electron density of 1019-1020 m-3, the estimated electron temperature Te for the plasma column is in the range of 3.1-2.6 eV.
It should be stressed that although voltage-current characteristics of the microdischarge were measured in present work, it cannot be applied for electric field determination in the plasma column, since the value of cathode fall voltage is unknown.
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