Ultralow nitrogen-doped carbon coupled carbon-doped Co3O4 microrods with tunable electron configurations for advanced Li-storage properties

Doping is a very effective way to optimize the electrochemical performance of electrodes by tuning the electron configurations on an atomic scale. Here, to obtain excellent Co3O4 electrodes for lithium ion storage, a meaningful defect-engineering of carbon-doping Co3O4 microrods strongly coupling with nitrogen-doped carbon (C-Co3O4@N-C) is designed and validated. Compared with unmodified Co3O4 microrods, the defect-rich C-Co3O4@N-C microrod electrode features a remarkably high initial Coulombic efficiency of 84.5% and specific capacity of 1130 mAh g(-1) at 0.2 A g(-1), excellent cycling stability (1265 and 1036 mAh g 1 capacity retention after 110 and 500 cycles at 0.2 A g(-1) and 1 A g(-1), respectively) and superior rate capacity (452 mAh g(-1) capacity retention after 3000 cycles at 5 A g(-1)). These results demonstrate that introducing rich defects by carbon dopants and nitrogen-doping carbon can effectively modulate the electron structure and accelerate the carrier transport of materials. This valid stratagem greatly elevates lithium-ion battery performance and can be further extended to other transition metal oxides and fields. (C) 2019 Elsevier Ltd. All rights reserved.