A hollow Fe ₃ C@N–C with frogspawn-like architecture was successfully constructed as an efficient sulfur host for high-rate and long-life lithium–sulfur batteries.

A micron-sized honeycomb-like carbon material (MHC) is prepared in a facile way using nano-CaCO₃ as a hard template. A novel electrode for lithium–oxygen batteries is fabricated and displays a superior discharge capacity as high as 5862 mA h g⁻¹. The higher electrode space utilization is attributed to its hierarchical pore structure, with intrinsic mesopores in the MHC particles for Li₂O₂ depositions and macropores among them for oxygen transport.

Nitrogen enriched mesoporous carbon (N-MCS) with extremely high mesopore volume and nitrogen content is prepared through a one-step hard template method. The N-MCS cathode shows excellent discharge performance in lithium–oxygen batteries. The pore space is better utilized due to its optimized pore structure and uniformly incorporated N.