| Summary: | Phosphorization of metal oxides/hydoxides to promote electronic conductivity as a promising strategy has attracted enormous attention for improving the electrochemical properties of anode material in lithium ion batteries. For this article, selective phosphorization from NiCo<sub>2</sub>O<sub>4</sub> to NiO/Ni<sub>2</sub>Co<sub>4</sub>P<sub>3</sub> microspheres was realized as an efficient route to enhance the electrochemical lithium storage properties of bimetal Ni-Co based anode materials. The results show that varying phosphorizaed reagent amount can significantly affect the transformation of crystalline structure from NiCo<sub>2</sub>O<sub>4</sub> to intermediate NiO, hybrid NiO/Ni<sub>2</sub>Co<sub>4</sub>P<sub>3</sub>, and, finally, to Ni<sub>2</sub>Co<sub>4</sub>P<sub>3</sub>, during which alterated sphere morphology, shifted surface valance, and enhanced lithium-ion storage behavior are detected. The optimized phosphorization with 1:3 reagent mass ratio can maintain the spherical architecture, hold hybrid crystal structure, and improve the reversibly electrochemical lithium-ion storage properties. A specific capacity of 415 mAh g<sup>−1</sup> is achieved at 100 mA g<sup>−1</sup> specific current and maintains at 106 mAh g<sup>−1</sup> when the specific current increases to 5000 mA g<sup>−1</sup>. Even after 200 cycles at 500 mA g<sup>−1</sup>, the optimized electrode still delivers 224 mAh g<sup>−1</sup> of specific capacity, exhibiting desirable cycling stability. We believe that understanding of such selective phosphorization can further evoke a particular research enthusiasm for anode materials in lithium ion battery with high performances.
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