An electrochemically grown three-dimensional porous Si@Ni inverse opal structure for high-performance Li ion battery anodes

Abstract

We report a facile method for the fabrication of a three-dimensional (3D) porous silicon@nickel (Si@Ni) inverse opal structure for Li ion batteries by using an electrodeposition method and a colloidal crystal as a sacrificial template. The Ni inverse opal structure was fabricated first by electrodeposition of Ni on the pre-formed colloidal crystal template, followed by removal of the template. Finally, the Si@Ni inverse opal structure was obtained by electrodeposition of Si onto the Ni inverse opal structure. The highly porous structure of the electrode containing a conductive and mechanically strong Ni scaffold could sufficiently accommodate volume expansion during the Si–Li alloying. A coin cell using the Si@Ni inverse opal structure as an anode exhibited a high charge capacity of 2548.5 mA h g⁻¹, stable cycling retention, and high rate performance without the need for binders or conducting additives.