Tin phosphides are attractive anode materials for ultrafast lithium-ion batteries(LIBs)because of their ultrahigh Li-ion diffusion capability and large theoretical-specific capacity.However,difficulties in synthesis and large size enabling electrochemical irreversibility impede their applications.Herein,an in situ catalytic phosphorization strategy is developed to synthesize SnP/CoP hetero-nanocrystals within reduced graphene oxide(rGO)-coated carbon frameworks,in which the SnP relative formation energy is significantly decreased according to density functional theory(DFT)calculations.The optimized hybrids exhibit ultrafast charge/discharge capability(260 mA·h·g-1 at 50 Ag-1)without capacity fading(645 mA·h g-1 at 2 A·g-1)through 1500 cycles.The lithiation/delithiation mechanism is disclosed,showing that the 4.0 nm sized SnP/CoP nanocrystals possess a very high reversibility and that the previously formed metallic Co of CoP at a relatively high potential accelerates the subsequent reaction kinetics of SnP,hence endowing them with ultrafast charge/discharge capability,which is further verified by the relative dynamic current density distributions according to the finite element analysis.

Chen Hu;Yanjie Hu;Aiping Chen;Xuezhi Duan;Hao Jiang;Chunzhong Li

Key Laboratory for Ultrafine Materials of Ministry of Education,Frontiers Science Center for Materiobiology and Dynamic Chemistry,School of Materials Science and Engineering,East China University of Science and Technology,Shanghai 200237,China;Shanghai Engineering Research Center of Hierarchical Nanomaterials,School of Chemical Engineering,East China University of Science and Technology,Shanghai 200237,China

工程（英文）

[1]Chen Hu;Yanjie Hu;Aiping Chen;Xuezhi Duan;Hao Jiang;Chunzhong Li-.Atomic Interface Catalytically Synthesizing SnP/CoP Hetero-Nanocrystals within Dual-Carbon Hybrids for Ultrafast Lithium-Ion Batteries)[J].工程（英文）,2022(11):154-160

Catalytically,SnP

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