Gas-liquid interfacial assembly and electrochemical properties of 3D highly dispersed α-Fe2O3@graphene aerogel composites with a hierarchical structure for applications in anodes of lithium ion batteries

摘要

Three-dimensional (3D) a-Fe2O3@graphene aerogel (a-Fe2O3@GA) composites with an a-Fe2O3 content as high as 54 wt% were prepared via a gas-liquid interfacial assembly method. It was found that the a-Fe2O3 nanoparticles were well dispersed and embedded into the 3D porous structure of graphene aerogel (GA). Compared with that (SBET = 82 m2 g−1) of pristine a-Fe2O3, the resulting composites exhibited much higher specific surface area (SBET = 261 m2 g−1). The composites used as anode materials for lithium ion batteries maintained a high reversible capacity of 745 mAh g−1 at a current density of 100 mA g−1 or more than 240 mAh g−1 at a current density of 2000 mA g−1 after 100 cycles, and exhibited superior stable electrochemical cycling performance and excellent rate capability. The superior electrochemical performances were attributed to the synergistic effects of the unique 3D porous structure of the composites with high contents of well dispersed a-Fe2O3.