Flexible and free-standing ternary Cd₂GeO₄ nanowire/graphene oxide/CNT nanocomposite film with improved lithium-ion battery performance

To realize flexible lithium-ion batteries (LIBs), the design of flexible electrode/current collector materials with high mechanical flexibility, superior conductivity and excellent electrochemical performance and electrical stability are highly desirable. In this work, we developed a new ternary Cd₂GeO₄ nanowire/graphene oxide/carbon nanotube nanocomposite (Cd₂GeO₄ NW/GO/CNT) film electrode. Benefiting from the efficient combination of GO and Cd₂GeO₄ NWs, our Cd₂GeO₄ NW/GO/CNT composite film exhibits a capacity of 784 mA h g^-1 after 30 cycles at 200 mA g^-1, which is 2.7 times higher than that of Cd₂GeO₄ NW/CNT film (290 mA h g^-1). At a higher rate of 400 mA g^-1 and 1 A g^-1, the Cd₂GeO₄ NW/GO/CNT film delivers a stable capacity of 617 and 397 mA h g^-1, respectively. Even at 2.5 A g^-1, it still exhibits a high rate capacity of 180 mA h g^-1. The flexible Cd₂GeO₄ NW/GO/CNT film clearly demonstrates good cycling stability and rate performance for anode materials in LIBs. This route may be extended to design other flexible free-standing metal germanate nanocomposite anode materials.