The invention provides a method for preparing a hetero-atom doped
porous carbon material through
carbonation of
biomass under the assistance of
molten salt. The method comprises the following steps: uniformly mixing
biomass powder, the
molten salt and a hetero-atom doped compound to obtain a product A, wherein the
molten salt contains LiCl and KCl, the
mass of LiCl accounts for 59 percent of that of the molten salt, and the
mass of KCl accounts for 59 percent of that of the molten salt; putting the product A in a
pipe furnace; carrying out high-temperature
calcination; cleaning with
distilled water to remove the molten salt and obtain the final product, namely the hetero-atom doped
porous carbon material. The method has the advantages that the
biomass is taken as a
raw material, and the molten salt containing hetero-atoms is taken as a
carbonization medium, so that the hetero-atoms can be introduced into the skeleton of the carbon material during the
pyrolysis and
carbonization process of the biomass synchronously and controllably, and the hetero-atom in-situ doped
porous carbon material is obtained finally. Compared with the conventional
doping method, the method provided by the invention have the advantages that the steps are simple; the cost is low; the operation is easy; the reactant purity is high; the application prospect is relatively good.