▎ 摘　　要

2D hybrid nanomaterials show great potential in reducing friction and energy dissipation of dry sliding both theoretically and experimentally. However, the achievement of low friction by introducing the hybrid nanomaterials in a macroscopic water-based environment remains a major challenge. Here, black phosphorus-graphene oxide (BP-GO) hybrid nanomaterials with a 2D layered structure are synthesized successfully. As water-based additives, the BP-GO hybrid nanomaterials enable the significant reduction of friction and wear. The lubrication mechanism proposed involves the easy interlayer shear that originated from the hydrophilization and unique microscopic heterojunction stacking structure of the 2D BP-GO hybrid nanomaterials. This study demonstrates the fascinating prospect of the 2D BP-GO hybrid nanomaterials toward advanced macroscopic lubricating properties under water.