Method for preparing carbon nanotube or carbon microtube

#1. Field of the Invention

#The invention relates to the field of carbon tube materials, and more particular to a method for preparing a hollow bamboo-shaped carbon nanotube or microtube.

#2. Description of the Related Art

#The invention is described hereinbelow with reference to the accompanying drawings, in which:

#FIG. 1 is a scanning electron microscope (SEM) image of a hollow bamboo-shaped carbon nanotube in accordance with Example 1;

#FIG. 2 is a SEM image of a cross section of a hollow bamboo-shaped carbon nanotube in accordance with Example 1;

#For further illustrating the invention, experiments detailing a method for preparing a carbon nanotube or a carbon microtube are described below. It should be noted that the following examples are intended to describe and not to limit the invention.

#A method for preparing a carbon nanotube or a carbon microtube, comprises: a) preparing a liquid polyacrylonitrile (LPAN) solution, stirring the LPAN solution at between 100 and 200° C. for between 100 and 200 h to yield a cyclized LPAN solution; b) heating the cyclized LPAN solution at between 200 and 300° C. for between 1 and 10 h to yield a thermally-oxidized polyacrylonitrile (OPAN) solution comprising a ladder structure; c) grinding, screening, and drying at room temperature the OPAN to yield a thermal oxidative precursor; d) calcining the thermal oxidative precursor at between 400 and 1000° C. for between 1 and 24 h in the presence of inert gas having a flow rate of between 10 and 500 mL/min to yield a carbonated precursor; and e) calcining the carbonated precursor at between 1000 and 1500° C. for between 1 and 10 h in the presence of the inert gas having a flow rate of between 10 and 500 mL/min to yield a carbon nanotube material; or calcining the carbonated precursor at between 1500 and 1800° C. for between 10 and 24 h in the presence of the inert gas having a flow rate of between 10 and 500 mL/min to yield a carbon microtube material.

#The method further comprises adding a doping agent to the cyclized LPAN solution and mixing for modifying the cyclized LPAN solution.