Boosting the electrochemical performance of nanoporous CuGe anode by regulating the porous structure and solid electrolyte interface layer through Ni-doping

Fabrication alloy-type anode into nanoporous structure demonstrate great potentials to solve the problems of their volume expansion and electrode pulverization upon cycling. However, the fine regulation of porous structure and quickly achieving a stable interface remains challenge for the alloy anode. Herein, we design and prepare a three-dimensional (3D) nanoporous CuGeAlNi alloy by chemical dealloying method. The corrosion resistance capability of Ni could regulate the dealloying process and thus morphology and porosity of the pre-fabricated CuGe alloy can be effectively tuned. A hierarchical porous structure with 10–80 nm large pores and 2–10 nm small pores on the ligament were obtained. The optimized nanoporous Ge-based anodes delivered a superior electrochemical performance, which presents a high reversible capacity of 540.9 mAh g⁻¹ after 200 cycles at a current density of 500 mA g⁻¹ and outstanding rate performance, which thus endowing a stable cycle performance. These results prove that the Ni-doping approach may offer a facile but effective way for boosting the performance of alloy-type anode for lithium-ion batteries (LIBs).