Construction of continuous Fe2O3 layer as self-supporting and long-life lithium storage anodes

• Self-supported SS@FO is fabricated via a simple oxidation technology in air. • SS@FO shows stable Li + storage performance in lithium ion battery. • The Fe 2 O 3 shells show hybrid-type Li + storage behaviors. In this work, controllable active oxide layer (mainly α -Fe 2 O 3 ) is in-situ fabricated on stainless steel fiber felt (SS@FO) via a simple oxidation technology in air. Used as anode for LIBs, the self-supporting SS@FO exhibits stable cyclic performance. The capacity can still retain 305.0 μAh/cm 2 after 400 cycles at 0.5 mA/cm 2 and 189.2 μAh/cm 2 after 800 cycles at 1 mA/cm 2 , respectively. It is found that the Fe 2 O 3 shells show hybrid-type (diffusion and capacitive-controlled processes) Li + storage behaviors. The stainless-steel core could not only significantly improve the electron transfer speed, leading to enhanced kinetics in the Li + insertion/extraction processes, but also buffer the volume changes of the α -Fe 2 O 3 shells, ensuring the good cyclic stability of SS@FO. This study can provide a reference for the design of low-cost, long-life and self-supporting electrodes for LIBs.