Impact of vacuum on the preparation of nanoporous copper through transient joule heating vapor phase dealloying

Copper nano-porous materials are commonly used functional materials with wide applications in catalysis and energy storage. This study investigates the influence of different vacuum degrees on the preparation of copper nano-porous metals using a transient Joule heating device via vapor phase de-alloying (VPD), and tests their performance as current collectors for lithium-ion batteries. The results show that the pore size of porous copper prepared at 20 Pa is 100 nm, with uniform distribution, and the sample has the lowest Zn content and smallest interplanar spacing of crystal phases, exhibiting an electrochemical activity specific surface area 317.6 times that of H65 brass. Furthermore, lithium-ion batteries made from porous copper produced at different vacuum degrees achieve discharge capacities of 420 and 435 mAh·g-1, higher than commercial copper foil-based lithium-ion batteries (350 mAh·g-1). By adjusting different vacuum degrees, the electrochemical performance of porous copper current collectors can be effectively improved.