Carbon nano-tube production by electrode microwave discharge in C_2H_2/H_2 and CH_4/H_2 mixture gases

摘要

The electrode microwave discharge can sustain the high-pressure plasma by the moderate microwave power. When a 2.45 GHz microwave was applied into the discharge chamber in which the carbon electrode of 3 λ/4(λ: microwave wavelength in vacuum) is set up along the chamber axis, the spherical plasma with a diameter of 10-15 mm could be produced at the top of the electrode in H_2 or He gas at the pressure higher than 100 Torr, followed by the electrode heating to the temperature higher than 1000 ℃. The plasma can produce thinner carbon nano-tubes on the nickel substrate in C_2H_2/H_2 mixture gas than in CH_4/H_2 mixture gases.