▎ 摘　　要

NOVELTY - Multi-level hole material graphene, where the hole diameter distribution curve of the material is graphene with a micro-pore distribution peak and a mesoporous distribution peak, and the resistance rate of the material graphene less than 1100 mΩ/cm. USE - The method for preparing 1500MPa grade pickling-free hot forming steel useful in fuel cell catalyst carrier and/or fuel cell catalyst (claimed). ADVANTAGE - The multi-level hole material graphene has low resistivity and good conductivity. The pore structure of the material graphene micro-pore and mesoporous, and multi-stage hole synergistic effect exhibits good catalytic activity. The preparation method of the graphene material is simple and efficient, the transition metal salt can be at normal temperature and normal pressure, alkali metal salt and/or alkali and carbon source directly to prepare precursor material, without using high temperature and high pressure reaction kettle self-assembly, and without using a large amount of organic solvent, the whole process only loss of carbon source, metal atoms can be recycled, and low preparation cost. DETAILED DESCRIPTION - AN INDEPENDENT CLAIM is also included for preparing the multi-level hole material graphene.