▎ 摘 要
Using first-principles density functional theory (DFT) calculations, we demonstrate that the heterointerface of black phosphorus and graphene (BP/Gr) should be a promising lubricant, especially under high pressure con-ditions. The ultralow interfacial frictional sliding motion is enabled by graphene oxide (GO) functional groups, such as epoxy and hydroxyl groups. These functional groups significantly modulate the interfacial charge dis-tribution to facilitate interfacial slip. The epoxy functional group enables a reduction in not only the bilayer adhesion but also the shear strength along the armchair direction by approximately 40% compared with that without functionalization. The potential energy surface (PES) calculation shows the possibility of an ultralow friction sliding process in BP/Gr and BP/GO due to the presence of almost frictionless paths. In addition, high -accuracy PES calculations predict an almost frictionless sliding path even under pressure. Interestingly, our calculation shows that the corrugation energy and shear strength of BP/Gr decrease under 10 GPa. We elucidated that the origin of the improved frictional properties under high pressure stems from the unique heterostructure of BP/Gr. These results consistently suggest that BP/Gr is promising lubricants for high-pressure applications, which can be further improved using a design principle of exploring optimal interfaces and functional groups.