Facile synthesis of Ni-11(HPO3)(8)(OH)(6)/rGO nanorods with enhanced electrochemical performance for aluminum-ion batteries

摘要

The electrochemical behaviors of the ultrashort nickel phosphite nanorods supported on reduced graphene oxide (Ni-11(HPO3)(8)(OH)(6)/rGO nanorods), as a candidate for cathodic applications in aluminum-ion batteries, are firstly investigated. Ni-11(HPO3)(8)(OH)(6)/rGO nanorods are synthesized by a facile solvothermal process. Ni-11(HPO3)(8)(OH)(6) and Ni-11(HPO3)(8)(OH)(6)/rGO cathodes both possess very high initial discharge capacities of 132.4 and 182.0 mA h g(-1) at a current density of 200 mA g(-1), respectively. In addition, the long-term cycling stability of the Ni-11(HPO3)(8)(OH)(6)/rGO cathode is further evaluated, exhibiting a discharge capacity of 49.2 mA h g(-1) even over 1500 cycles. More importantly, the redox reaction mechanism of the Ni-11(HPO3)(8)(OH)(6) cathode for aluminum-ion batteries revealed that Ni-11(HPO3)(8)(OH)(6) is partially substituted with Al3+ to form AlmNin(HPO3)(8)(OH)(6) and metallic Ni in the nanorod-like Ni-11(HPO3)(8)(OH)(6) cathodes during the discharge process. These findings are of great significance for the further development of novel materials for aluminum-ion batteries.