Building Fast Diffusion Channel by Constructing Metal Sulfide/Metal Selenide Heterostructures for High-Performance Sodium Ion Batteries Anode.

Wang, Tianshuai; Legut, Dominik; Fan, Yanchen; Qin, Jian; Li, Xifei; Zhang, Qianfan · Nano Lett · 2020

basic_science · Level V

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Abstract

Heterostructure engineering is one of the most promising modification strategies toward improving sluggish kinetics for the anode of sodium ion batteries (SIBs). Herein, we report a systemic investigation on the different types of heterostructure interfaces' effects of discharging products (Na<sub>2</sub>O, Na<sub>2</sub>S, Na<sub>2</sub>Se) on the rate performance. First-principle calculations reveal that the Na<sub>2</sub>S/Na<sub>2</sub>Se interface possesses the lowest diffusion energy barrier (0.39 eV) of Na among three kinds of interface structures (Na<sub>2</sub>O/Na<sub>2</sub>S, Na<sub>2</sub>O/Na<sub>2</sub>Se, and Na<sub>2</sub>S/Na<sub>2</sub>Se) due to its smallest recorded interface deformation, similar electronegativity, and lattice constant. The experimental evidence confirms that the metal sulfide/metal selenide (SnS/SnSe<sub>2</sub>) hierarchical anode exhibits outstanding rate performance, where the normalized capacity at 10 A g<sup>-1</sup> compared to 0.1 A g<sup>-1</sup> is 45.6%. The proposed design strategy in this work is helpful to design high rate performance anodes for advanced battery systems.