F127 assisted fabrication of Ge/rGO/CNTs nanocomposites with three-dimensional network structure for efficient lithium storage

• Published in: Chinese chemical letters Vol. 35; no. 9; p. 109273
• Main Authors: Gu, Hui, Gao, Mingyue, Shen, Kuan, Zhang, Tianli, Zhang, Junhao, Zheng, Xiangjun, Guo, Xingmei, Liu, Yuanjun, Cao, Fu, Gu, Hongxing, Kong, Qinghong, Xiong, Shenglin
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.09.2024
• Subjects: Cycle stability; F127 assisted fabrication; Ge/rGO/CNTs nanocomposites; Lithium-ion batteries; Three-dimensional carbon network; Lithium-ion batteries; Three-dimensional carbon network; F127 assisted fabrication; Cycle stability; Ge/rGO/CNTs nanocomposites
• ISSN: 1001-8417; 1878-5964
• DOI: 10.1016/j.cclet.2023.109273

To solve the volume expansion and poor electrical conductivity of germanium-based anode materials, Ge/rGO/CNTs nanocomposites with three-dimensional network structure are fabricated through the dispersion of polyethylene-polypropylene glycol (F127) and reduction of hydrogen. An interesting phenomenon is discovered that F127 can break GeO2 polycrystalline microparticles into 100 nm nanoparticles by only physical interaction, which promotes the uniform dispersion of GeO2 in a carbon network structure composed of graphene (rGO) and carbon nanotubes (CNTs). As evaluated as anode material of Lithium-ion batteries, Ge/rGO/CNTs nanocomposites exhibit excellent lithium storage performance. The initial specific capacity is high to 1549.7 mAh/g at 0.2 A/g, and the reversible capacity still retains 972.4 mAh/g after 100 cycles. The improved lithium storage performance is attributed to that Ge nanoparticles can effectively slow down the volume expansion during charge and discharge processes, and three-dimensional carbon networks can improve electrical conductivity and accelerate lithium-ion transfer of anode materials. An interesting phenomenon is found that F127 can disperse GeO2 polycrystalline microparticles into nanoparticles, which facilitates to prepare Ge/rGO/CNTs nanocomposites with uniform dispersion. Evaluated as anode material of LIBs, Ge/rGO/CNTs nanocomposites has higher specific capacity and more stable cycling performance. [Display omitted]