Hollow design of ternary metal oxide nanostructures based on Kirkendall effect for long-life and high-rate lithium ion batteries

Metal oxides have great potential as high-capacity anodes in lithium ion batteries (LIBs), but suffer from poor conductivity and severe pulverization during repeated lithiation/delithiation cycles. Herein, hollow ternary metal oxide (h-TMO) decorated three-dimensional (3D) carbon nanosheet frameworks (h-TMO/CNFs) are successfully prepared via the metal nitrate assisted blowing process and subsequent Kirkendall effect driven hollowing process. The hollow structures and ternary metal oxide components facilitate to keep structural integrity during lithiation/delithiation processes, while 3D porous networks provide fast electron-transfer pathways and reduced ion diffusion distance for fast reaction kinetics. As a result, the resulting h-TMO/CNFs anodes demonstrate high capacities of 900 mAh g^‒1 after 100 cycles at 0.1 A g^‒1 and 307 mAh g^‒1 at 10 A g^‒1, superior to most reported similar electrodes. And the assembled h-TMO/CNFs//LiFePO₄ full LIBs can display a high initial discharge capacity 150 mAh g^‒1 at 0.1 A g^‒1. The hollow design strategy based on Kirkendall effect opens up a new avenue to construct multicomponent nanostructures for high-performance LIBs.

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