LAUSR

Abstract Cr 2 O 3 is of high theoretical capacity for lithium-ion (Li + ) storage. However, its cyclic stability is very poor due to the large volume change during lithiation/delithiation. In addition, the low conductivity of Cr 2 O 3 blocked the fast transfer of electrons, resulting in an inferior rate capacity. In this study, we design yolk-shell Cr 2 O 3 composites using carbon/Cr 2 O 3 as core and graphene as shell to improve the conductivity of electrode materials and provide spaces for the volume change of Cr 2 O 3 . Therefore, this composites (Cr 2 O 3 @C@G) exhibit a higher specific capacity and stable cyclic performance achieved the remarkable reversible capacity of 648 mA hg −1 after 120 cycles at 0.1 A g −1 , even a capacity of 347 mA hg −1 is obtained after 600 cycles at 1 A g −1 . Due to the space between carbon sphere and graphene, they not only effectively alleviate the volume expansion of Cr 2 O 3 , but also enhance the electrochemical properties of the composites. Eventually the electronic conductivity and Li + diffusion rate more pleasantly during cycling due to the excellent structural characteristics.