SnO@a-Si core-shell nanowires on free-standing CNT paper as a thin and flexible Li-ion battery anode with high areal capacity.

Here, we report 3D hierarchical SnO nanowire (NW) core-amorphous silicon shell on free-standing carbon nanotube paper (SnO@a-Si/CNT paper) as an effective anode for flexible lithium-ion battery (LIB) application. This binder-free electrode exhibits a high initial discharge capacity of 3020 mAh g with a large reversible charge capacity of 1250 mAh g at a current density of 250 mA g. Compared to other SnO NW or its core-shell nanostructured anodes, the fabricated SnO@a-Si/CNT structure demonstrates an outstanding performance with high mass loading (∼5.