Ge Nanoparticles in MXene Sheets: One-step Synthesis and Highly Improved Electrochemical Property in Lithium-ion Batteries
(2.University of Chinese Academy of Sciences, Chongqing, China 400714)
【Abstract】Ge nanoparticles were synthesized uniformly on MXene sheets via a one-step chemical solution method. The morphology of Ge/MXene was characterized by SEM and TEM. The formation process and optimized synthesis condition were analyzed carefully. Ge/MXene was used as anode for lithium-ion batteries. Their electrochemical performance, including capacity, rate and cycling stability, were tested and evaluated. Ge/MXene exhibited a greatly improved capacity of 1 200 mAh/g during the first hundred cycles at 0.2C with a loading of 1 mg/cm2. A capacity of 450 mAh/g at a higher loading of 2 mg/cm2 was obtained after 100 cycles. The excellence in electrochemistry was attributed to the high conductivity of MXene and its accommodable interlayer space.
【Keywords】 MXene; Ge nanoparticles; lithium-ion batteries; anode materials;
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