MoS2 anchored free-standing three dimensional vertical graphene foam based binder-free electrodes for enhanced lithium-ion storage

The vertical graphene with hierarchical three-dimensional network architecture is a promising substrate for high energy and power density Li-ion battery due to its large surface area, inherent three-dimensional network and excellent ion transport property. Three dimensional vertical graphene (3DVG) is synthesized via plasma enhanced chemical vapor deposition (PECVD) using cost-effective and environment-friendly natural oil of M. alternifolia as precursor. The MoS2 nanosheets are then anchored on free-standing 3DVG by hydrothermal method to make the binder free MoS2@3DVG anode of a Li-ion battery. The MoS2@3DVG electrodes deliver an enhanced capacity of 670 mAh g−1 with the capacity retention of 99% after 30 cycles at 100 mA g−1, much better than that of the reference sample of MoS2@3DG (550 mAh g−1 at 100 mA g−1) which uses 3D planar graphene. Superior performance of the vertical graphene based electrode is attributed to the unique hierarchical structure and densely packed reactive edges of the as-synthesized 3DVG. The versatility of plasma-assisted natural precursor based vertical graphene as functional nano-structured substrate for MoS2, as active material, for advanced energy storage devices is demonstrated.