Red phosphorus encapsulated in 3D N-doped porous carbon nanofibers: an enhanced sodium-ion battery anode material.

We report a sodium-ion battery anode design using red phosphorus encapsulated in nitrogen-doped porous carbon nanofibers that mitigates volume expansion and poor conductivity issues, enhancing battery performance. Density functional theory calculations suggest nitrogen doping promotes robust phosphorus interactions, and finite element analysis indicates the design controls volume expansion.