A novel strategy of dual in-situ synthesis for graphene/Cu composites with high strength and high electrical conductivity

Graphene-reinforced copper matrix composites still face challenges in graphene structural damage during fabrication and poor interfacial bonding between graphene and copper. This study introduces an innovative dual in-situ synthesis strategy employing yttrium acetate tetrahydrate (YACT) as a multifunctional precursor. In-situ thermal analysis reveals that organic gases (C₂H₂) generated during YACT decomposition serves as the primary carbon source for graphene formation, while the released reductive gases (H₂) acting as reducing agents, avoiding extra reduction steps. Notably, the residual Y₂O₃ nanoparticles derived from YACT decomposition established robust interfacial coupling through dual coherent bridging between graphene and copper matrix. This unique architecture enhanced interfacial load transfer efficiency by 231 %, enabling full exploitation of graphene's theoretical strength. The optimized composites exhibited exceptional mechanical-electrical synergy: 453 MPa ultimate tensile strength (256 % of pure copper), 25.1 % ductility, and 99.2 % IACS electrical conductivity. These findings suggest that prioritizing analysis of thermal decomposition products from solid carbon sources optimizes copper-graphene composite design. Moreover, eliminating external reduction processes and synergistically integrating precursor decomposition with interfacial engineering enable scalable production of high-performance copper-graphene composites.