Patent ID: 8277771
Filing Date: 2012-10-02
Classification: B82Y,C01B,D01F,Y10T

Abstract:
1. A method for fabricating a continuous vapor grown carbon fiber, comprising: (a) providing a substrate which has a catalyst on its surface; (b) placing said substrate in a furnace said furnace having a reaction zone; (c) loading said furnace with hydrogen, ammonia, or combinations thereof until the gas pressure of the reaction zone reaches one atmosphere; (d) adjusting the temperature of said furnace to 400° C. to 900° C. to proceed with a heat treatment for 10 minutes to 2 hours; (e) adding a carbon-containing compound into said furnace; (f) adjusting the ratio of said carbon-containing compound and said hydrogen, ammonia, or combinations thereof until the gas pressure of the reaction zone reaches one atmosphere; (g) adjusting the temperature of said furnace to 700° C. to 1200° C. to crack said carbon-containing compound, and thereby forming a carbon fiber having a diameter of from one micrometer to several ten micrometers; and wherein said substrate is a 40 cm×10 cm substrate having an iron catalyst on its surface and is placed in said reaction zone of said furnace; argon is loaded into said reaction zone at a mass flow rate of 1000 sccm until the gas pressure of said reaction zone reaches one atmosphere, said reaction zone is heated to 700° C.; and the argon is replaced with hydrogen by loading hydrogen at a mass flow rate of 600 sccm to proceed with a heat treatment of said catalyst for 20 minutes, after which the temperature of said reaction zone is further elevated to 1100° C., and methane is loaded into said reaction zone at a mass flow rate of 300 sccm until the concentration of methane is 33% by volume and after 2-hours of dwell time at 1100° C., a continuous vapor grown carbon fiber having a diameter of 6 μm and a length of 40 cm is obtained and the length of the carbon fiber is equal to that of the substrate.