Wheat-like Co3O4 on carbon derived from silk as anode materials for enhanced lithium storage.

The design and preparation of hierarchical porous transition metal oxide-carbon matrix anodes with unique structure play the significant role in highly reversible lithium ion batteries. Herein, hierarchical porous wheat-like Co 3 O 4 on carbon derived from natural silk (named as SK@Co 3 O 4) nanobelts are fabricated successfully by one-step hydrothermal technique and ensuing high-temperature calcination. The wheat-like SK@Co 3 O 4 nanobelts consist of a number of nanobeams. The length of nanobelts is around 1 µm whereas the diameter is 200 nm. Moreover, the SK@Co 3 O 4 anode for lithium ion batteries retains 1108 mA h g−1 following 100 cycles at 100 mA g−1, 707 mA h g−1 and 709 mA h g−1 after 150 cycles at 2 A g−1, 625 mA h g−1 and 617 mA h g−1 after 150 cycles at 5 A g−1,which show extraordinary cycle stability of the composite. The remarkable lithium storage property results from the hierarchical porous structure and this structure can not only provide a short ion transport path but also raise the area of contact between the electrolyte and electrode. [Display omitted] • Wheat-like Co 3 O 4 on carbon derived from silk was synthesized. • Silk was used as carbon source. • SK@Co 3 O 4 nanobelts showed high lithium storage performance. [ABSTRACT FROM AUTHOR]