Page 60 - Synthesis of Functional Nanoparticles Using an Atmospheric Pressure Microplasma Process - LiangLiang Lin
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Chapter 3
Figure 3.5 (a) SEM image of nanoparticles synthesized at 1.05 W and 323.15 K. (b-d) Corresponding EDX mapping of C (b), Fe (c) and O (d) elements. (e) Overall EDX spectrum
3.3.4 TEM Analysis
Figure 3.6 shows representative TEM images of nanoparticles synthesized at plasma power of 1.05 W (a) and 2.27 W (b). These nanoparticles are prepared at a total gas mixture flow rate of 100 ml/min, with ferrocene concentration of 29.0 ppm during synthesis process. Both pictures indicate that due to the magnetic property, nanoparticles agglomerate together. However, it is observed that nanoparticles synthesized at low plasma power have a smaller size and relatively more uniform compared with particles prepared at high power, which is probably related to thermal effects. A similar phenomenon was also reported in case of Ni nanoparticles preparation from nickelocene, where higher power resulted in larger-sized particles.25

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