Atomic Interface Catalytically Synthesizing SnP/CoP Hetero-Nanocrystals within Dual-Carbon Hybrids for Ultrafast Lithium-Ion Batteries. (November 2022)

• Record Type: Journal Article
• Authors: Hu, Chen; Hu, Yanjie; Chen, Aiping; Duan, Xuezhi; Jiang, Hao; Li, Chunzhong
• Is Part Of: Engineering. Volume 18(2022)
• Page Start: 154
• Page End: 160
• Publication Date: 2022-11
• Subjects: Catalytic phosphorization -- SnP -- Hetero-nanocrystals -- Fast charging -- Li-ion batteries; Engineering -- Periodicals; Engineering -- China -- Periodicals; 620.005
• DOI: 10.1016/j.eng.2021.11.026
• Languages: English
• ISSNs: 2095-8099

Abstract

Graphical abstract: Abstract: 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 A·g − 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.