(2.中国科学院大学, 重庆 400714)
【摘要】通过化学溶液法一步制备锗/MXene复合材料,在MXene表面均匀负载了锗金属纳米颗粒。采用SEM和TEM对Ge/MXene复合材料进行了微观形貌分析,探索了复合材料的形成过程,结果表明,Ge/MXene复合材料是二维结构形貌,其元素分布均一。用Ge/MXene复合材料制备了电极,并组装成纽扣电池进行充放电性能测试,对电池的比容量、倍率、循环稳定性能进行了系统分析。测试结果表明,Ge含量为50%时的电化学性能最佳,0.2C下第5～100圈的容量稳定在1200 m Ah/g,载量为1 mg/cm2;载量提高到2 mg/cm2时的比容量依然能达到450 m Ah/g。
【基金资助】 中国科学院青年创新促进会(2019374); 中国科学院重庆绿色智能技术研究院青年创新基金(Y82A240H10); 重庆市留学归国人员创新创业支持计划(cx2018152);
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;
【Funds】 Youth Innovation Promotion Association of the Chinese Academy of Sciences (2019374); CCIGIT Young Innovators Awards (Y82A240H10); Chongqing Innovators Program for Returned Overseas Scholars (cx2018152);
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