Affiliation:
1. International Joint Research Laboratory of New Energy Materials and Devices of Henan Province, School of Physics and Electronics, Henan University , Kaifeng 475004, People's Republic of China
Abstract
Sodium-ion batteries (SIBs) have been widely researched due to their abundant resource and inherent safety. However, the major challenge for further commercialization of SIBs is the absence of low-priced anode electrodes with high reversible capacity and durability. Herein, a hierarchical heterogeneous structure of FeS2/SnS2@C nanocubes with rich two-dimensional mosaic-like heterointerface and N/S co-doped carbon wrapping is constructed and synthesized, to achieve ultrahigh reversible capacity and long cycling stability as anode of SIBs. Combining x-ray photoelectron spectroscopy, ion diffusion kinetic analysis, and in situ x-ray diffraction, the exquisite hierarchical heterogeneous structure of FeS2/SnS2@C could promote charge/electrons transfer and accelerate ion diffusion kinetics. As expected, the FeS2/SnS2@C anode shows superior reversible capacity (867.5 mA h g−1 at 0.1 A g−1), good rate performance (718.9 mA h g−1 at 5.0 A g−1), and long cycle stability (738.0 mA h g−1 after 1200 cycles at 5.0 A g−1) with Na metal as counter electrode. This work proves that the effectiveness of heterojunction interfaces for promoting Na+ diffusion is highlighted by such capabilities.
Funder
National Natural Science Foundation of China
China Postdoctoral Science Foundation
Foundation of Henan Educational Committee