Nano-sized FeSe2 decorated rGO as a potential anode material with enhanced lithium-ion storage

FeSe 2 @reduced graphene oxide (rGO) composite was prepared by a facile one-step hydrothermal technique with FeSe 2 nanoparticles uniformly achored on rGO nanosheets . The nano-sized FeSe 2 particles effectively reduce the transfer length of Li ion and increase the sufficient contact area between the electrolyte and active material. Moreover, rGO can not only improve the electrical conductivity , but also prevent the agglomeration of nano-sized FeSe 2 , as well as accommodate the volume expansion and strain generated from the charge/discharge process. As an anode material applied in Li-ion storage, FeSe 2 /rGO composite delivers superior specific capacity of 1167.6 mAh/g, good cycling stability (908.2 mAh g −1 after 120 cycles at the current density of 500 mA g −1 ) and high-power characteristics (728.0 mAh g −1 at 1000 mA g −1 ), due to coexistent Li-ion storage mechanisms of surface capacitive behavior and diffusion-controlled process.