Low-temperature synthesis method of low-dimensional hexagonal boron nitride (sheet, tube and fiber)

The invention belongs to the field of inorganic nonmetals, and discloses a low-temperature synthesis method of low-dimensional hexagonal boron nitride (sheet, tube and fiber), which comprises the following steps: by taking KFeO2 as a catalyst and amorphous boron powder as a boron source, reacting a mixture of the KFeO2 and the amorphous boron powder at 700-1000 DEG C under the condition of an N-element-containing atmosphere to obtain a low-dimensional hexagonal boron nitride material; or boric acid serving as a boron source and urea or melamine serving as a nitrogen source are jointly dissolved to obtain a mixed solution, then low-temperature ultrasonic treatment or electrostatic spinning and freeze drying are carried out on the mixed solution, reaction is carried out under the condition of protective gas at the temperature of 700-1000 DEG C, and therefore the low-dimensional hexagonal boron nitride material is obtained. The novel method for synthesizing the h-BN at the low temperature is different from the m