Black fungus derived N-doped carbon decorated with cobalt nanoparticles for efficient sodium storage.

Activating carbon materials with superb capacity, kinetics, and stability for sodium storage is desirable for sodium-ion batteries (SIBs), and heteroatom doping is believed as the effective strategy. Herein, ultrafine Co nanoparticles decorated nitrogen-doped carbon is prepared by the pyrolysis of black fungus infiltrated with Co(NO 3) 2 as SIBs anode material. Impressively, Co/NC exhibits efficient sodium storage properties of high specific capacity (345.7 mAh g−1 at 0.1 A g−1), good rate performance (158.2 mAh g−1 at 5 A g−1), and stable cyclic property (218.5 mAh g−1 at 1 A g−1 after 1000 cycles). Incorporation of N and Co produces defects and active sites, causing pseudocapacitive contributed sodium storage behavior with excellent electrochemical kinetics and structure stability. This study provides a reference to prepare high-performance carbon anodes using sustainable biomass materials. [Display omitted] • Co nanoparticles decorated N-doped carbon is prepared as SIBs anode. • Biomass of black fungus infiltrated with Co(NO 3) 2 are used as raw material. • Expanded carbon interlayer is favorable for Na+ insertion. • Pseudocapacitive behavior contributes to fast and large Na+ storage. • Excellent electrochemical Na+ storage performances are achieved. [ABSTRACT FROM AUTHOR]