Hexagonal boron nitride belongs to the hexagonal crystal system and has a hierarchical structure similar to graphite, hence it is called white graphite. The comparison between its crystal structure and graphite structure is shown in Table 3, where each layer has B and N atoms arranged in a hexagonal ring network. The atoms within the layer form strong covalent bonds, resulting in a tight structure. The interlayer is bound by molecular bonds, which are weak and therefore prone to weakening. The interlayer B-N atomic spacing is 0.142nm, and the elastic modulus E is 910Gpa, while the interlayer atomic spacing is 0.335nm. The elastic modulus is only 30 Gpa. BN and graphite not only have the same structure, but also have very similar lattice constants.