The invention discloses a preparation method and application of a
nitrogen-doped self-supporting
nanofiber membrane. The preparation method of the
nitrogen-doped self-supporting
nanofiber membrane comprises the following steps: S1, accurately weighing a solute and a
solvent, placing the solute and the
solvent in an
oil bath pan at 40-80 DEG C, and stirring for 5-20 hours at a constant temperature to prepare a
spinning solution; S2, preparing the
spinning solution prepared in the S1 into a composite
nanofiber membrane, placing the composite nanofiber membrane in a
drying box to remove a
solvent,
cutting the composite nanofiber membrane into a certain size, and pressing the
fiber membrane by using a
graphite sheet with a
smooth surface; S3, putting the
fiber membrane obtained in S2 into a
quartz tube furnace, and carrying out heat preservation for 1-2 hours in an
air atmosphere at 260-280 DEG C, then carrying out heat preservation for 1-3 hours in a
nitrogen atmosphere of 600-800 DEG C, and carrying out
carbonization treatment, and after the reaction is finished, cooling along with the furnace to
room temperature to obtain the nitrogen-doped self-supporting nanofiber membrane. The nitrogen-doped self-supporting nanofiber membrane prepared by the method has high storage capacity and high electrochemical performance, and can be directly used as an SIB negative
electrode material.