High-performance cathode promoted by reduced graphene oxide nanofibers with well-defined interconnected meso-/micro pores for rechargeable Li-Se batteries

Abstract

Highly conductive nanostructures comprising one-dimensional (1D) reduced graphene oxide (rGO) nanofibers(NFs) and bimodal pores i.e., meso-/micropores, as efficient cathode hosts (Bi-P-rGO) for Li–Se batterieswere prepared. The highly conductive rGO matrix acts as a self-supporting skeleton to enhance thestructural integrity of the nanostructure besides providing numerous conducting pathways for rapidcharge transfer. Moreover, highly interconnected chain-like mesopores guarantee efficient electrolytepercolation, whereas the micropores offer highly active material impregnation. Correspondingly, Bi-PrGO@Se as a high-performance cathode was visualized, which demonstrated an overall enhanced electrochemicalperformance such as excellent rate capability (up to 20.0C) and overwhelming long-termcycling stability (73% capacity retention at the end of 800cycles with an average capacity decay rate ofjust 0.03% per cycle at 0.5C rate). The exceptional electrochemical performance of the Bi-P-rGO@Se cathodecan be attributed to its highly porous structure, which promises efficient electrolyte infiltration anddiffusion of charged species, high active material utilization within micropores, availability of conductivepathways for fast charge transfer, and high structural integrity. Therefore, we anticipate that the structuraland electrochemical results presented in this work will provide significant insights into the synthesisof high-performance porous and conductive nanostructures for a wide range of applications.