▎ 摘　　要

Graphene is widely used as a barrier at the solid-solid and gas-solid state interface. However, the use of graphene as a barrier at the liquid-solid interface has been rarely reported, particularly in the case of a liquid-state metal and a solid-state metal interface. Herein, a graphene layer is synthesized on a Cu foil, and single-layer and bilayer graphene is detected via Raman spectroscopy. The interfacial intermetallic compound between eutectic Sn-58Bi alloy with a melting temperature of 138 degrees C and Cu with a melting temperature of 1085 degrees C can be significantly suppressed by graphene using different reflow temperatures (180 degrees C and 300 degrees C) and reflow times (144-625 s). Cu diffusion through graphene is visible in the Sn-Cu intermetallic compound (IMC) formations in the 5B58 solder and at the interface after the reflow processes. We found that the activation energy of Cu diffusion through graphene into the liquid-state graphene is similar to 32.6 kJ/(mol.k), which is higher than that attained without graphene. Therefore, the findings of this study show that graphene is a promising diffusion barrier for the liquid-solid interface.