Near‐Theoretical Oxidation Resistance in Copper Powder Enabled by Scalable Plasma‐Assisted Few‐Layer Graphene Encapsulation

Abstract Copper (Cu) powders offer exceptional conductivity and cost advantages for the semiconductor industry, but their strong oxidative susceptibility severely limits practical deployment. a tandem plasma‐enhanced powder synthesis (TaPPS) platform is proposed that synergizes plasma‐driven powder spheroidization and in situ chemical vapor deposition to realize tailored few‐layer graphene encapsulation on Cu powders (Gr@Cu) and enables continuous production at a rate of 4.38 kg h −1 . The engineered few‐layer graphene host confers dual functionality that ensures robust oxidation resistance: a quasi‐neutral outer layer suppresses electron transport and oxidative degradation, and an electron‐rich interfacial layer enhances Cu adhesion and acts as an oxygen diffusion barrier. Consequently, the Gr@Cu powder has an onset oxidation temperature of 458 °C, 130% higher than that of its unencapsulated counterpart (≈200 °C), and retains 70% of its conductivity (99 S cm −1 ) after exposure to 300 °C for 1 h. This work thus establishes a scalable strategy to fabricate oxidation‐resistant metal powders for high‐temperature electronics, helping to pave the way for the broad industrial adoption of graphene‐armored metals.