Gas and pressure effects on the synthesis of amorphous carbon nanotubes

The effects of gas, pressure and temperature on the production of amorphous carbon nanotubes were investigated using an arc discharging furnace at controlled temperature. Co/Ni alloy powder was used as catalyst. The discharge current was 80 A and voltage was 32 V. The optimal parameters were obtained: 600°C temperature, hydrogen gas and 500 torr pressure. The productivity and purity of amorphous carbon nanotubes are 6.5 gram per hour and 80%, respectively. The diameter of the amorphous carbon nanotubes is about 7-20 nm.