Fabrication of Heat Exchanger in Thermoacoustic Motor by Thin Layers of Fully Aligned Array Carbon Nanotubes

A silicon substrate was developed for use in thermoacoustic motors as heat exchangers. Acetylene gas (C2H2) as a carbon source of argon gas (Ar) as a carrier gas for hydrogen gas (H2) is used to recover nanoparticles and iron nanoparticles as a catalytic source for carbon nanotube array growth. The reaction was carried out in a 48 cm long quartz tube and the gases were injected with a specified flow rate. Increasing the growth time from 10 to 30 min, there was little change in the diameter distribution and density of the synthesized carbon nanotube arrays. However, the thickness of the arrays increased from 15.62 to 16.76 μm. Carbon nanotubes grown at 30 min had better growth. The thicknesses (lengths) of the carbon nanotube arrays synthesized at temperatures of 750 and 800 °C were 75.42 and 60.98 μm, respectively. In general, the samples synthesized at optimum growth time and temperature of 30 min and 750 °C on the layered silicon substrate (with iron nanoparticles) by magnetic sputtering were quite desirable for use as a thermocouple converter.