Nitrogen-doped porous carbon as cathodes for aluminum-ion batteries

Aluminum-ion batteries are favorable for the next generation of rechargeable batteries by virtue of their high theoretical energy density, high safety and low cost. Graphite with excellent electronic conductivity and large surface area is likely to be the most pleasurable cathode material for aluminum-ion batteries. However, due to the lack of high-performance cathodes and cost-effective electrolytes, aluminum-ion batteries are greatly hindered. Herein, a nitrogen doped three-dimensional porous carbon material cathode (N-3PC) with controlled porous and disordered structures is synthesized via a facile heating reaction in oil bath combined with sintering method. Moreover, the controlled porous structures by the Zn(NO3)2 pore-forming agent method support a very large specific surface area, which is beneficial to a relatively high initial Coulombic efficiency. In terms of open porous structures of N-3PC, the increased disordered structures can not only benefit the diffusion of Al3+ ions but also enlarge the reversible capacity of Al storage. When applied as cathode materials for aluminum-ion batteries, N-3PC cathode showcases rosy rate capability (33 mA h g−1 at 500 mA g−1) and perfect reversible capacity (13 mA h g−1 at a high current density of 2000 mA g−1). Furthermore, the high-performance N-3PC cathode material is prepared via a green approach stemming from low-cost and Zn(NO3)2 template, demonstrating a feasible development of carbon cathode materials for aluminum-ion batteries.