Formation, lithium storage properties, and mechanism of nanoporous germanium fabricated by dealloying

Shengzhen Wang; Wensheng Ma; Wanfeng Yang; Qingguo Bai; Hui Gao; Zhangquan Peng; Zhonghua Zhang

doi:10.1063/5.0067237

Formation, lithium storage properties, and mechanism of nanoporous germanium fabricated by dealloying

J Chem Phys. 2021 Nov 14;155(18):184702. doi: 10.1063/5.0067237.

Authors

Shengzhen Wang¹, Wensheng Ma¹, Wanfeng Yang¹, Qingguo Bai¹, Hui Gao¹, Zhangquan Peng², Zhonghua Zhang¹

Affiliations

¹ Key Laboratory for Liquid-Solid Structural Evolution and Processing of Materials (Ministry of Education), School of Materials Science and Engineering, Shandong University, Jingshi Road 17923, Jinan 250061, People's Republic of China.
² Laboratory of Advanced Spectro-electrochemistry and Li-ion Batteries, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, People's Republic of China.

PMID: 34773946
DOI: 10.1063/5.0067237

Abstract

Germanium (Ge) has become a promising anode material for lithium-ion batteries (LIBs) due to its high theoretical capacity and decent electron/ion conductivity, but it exhibits inferior lifespan caused by dramatic volume variations during the (de)lithiation process. Herein, hierarchically, nanoporous Ge (np-Ge) was fabricated by the combination of selective phase corrosion with chemical dealloying. As an anode for LIBs, the np-Ge electrode exhibits marvelous cycling stability with capacity retentions of 1060.0 mA h g^-1 at 0.2 A g^-1 and 767.1 mA h g^-1 at 1 A g^-1 after 100 cycles. Moreover, the electrode shows excellent rate capability with a capacity retention of 844.2 mA h g^-1 at 5 A g^-1. Noticeably, the (de)lithiation mechanisms of np-Ge and porous Si-Ge (p-Si₆Ge₄) were unveiled by operando X-ray diffraction.