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

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 (Na2O, Na2S, Na2Se) on the rate performance. First-principle calculations reveal that the Na2S/Na2Se interface possesses the lowest diffusion energy barrier (0.39 eV) of Na among three kinds of interface structures (Na2O/Na2S, Na2O/Na2Se, and Na2S/Na2Se) due to its smallest recorded interface deformation, similar electronegativity, and lattice constant. The experimental evidence confirms that the metal sulfide/metal selenide (SnS/SnSe2) hierarchical anode exhibits outstanding rate performance, where the normalized capacity at 10 A g–1 compared to 0.1 A g–1 is 45.6%. The proposed design strategy in this work is helpful to design high rate performance anodes for advanced battery systems.

Yolk‐Shell‐Structured Nanospheres with Goat Pupil‐Like S‐Doped SnSe Yolk and Hollow Carbon‐Shell Configuration as Anode Material for Sodium‐Ion Storage

“…The high‐resolution Sn 3d spectrum in Figure 2b is fitted by two obvious peaks located at 485.9 eV (Sn 3d 5/2 ) and 494.3 eV (Sn 3d 3/2 ), which correspond to Sn 2+ in the SnSe bonding states. [ 17,22 ] The small peaks at 484.4 and 492.9 eV at lower binding energies can be assigned to Sn 2+ in the SnS bonding states. [ 17,23 ] The Se 3d spectrum in Figure 2c exhibits two obvious peaks at 53.5 eV (Se 3d 5/2 ) and 54.7 eV (Se 3d 3/2 ), which indicates the presence of SnSe bonding states.…”

“…[ 17,22 ] The small peaks at 484.4 and 492.9 eV at lower binding energies can be assigned to Sn 2+ in the SnS bonding states. [ 17,23 ] The Se 3d spectrum in Figure 2c exhibits two obvious peaks at 53.5 eV (Se 3d 5/2 ) and 54.7 eV (Se 3d 3/2 ), which indicates the presence of SnSe bonding states. [ 24 ] In addition, the broad peak at 58.1 eV corresponds to the SeO bond, which is related to the tin selenite phase formed by the surface oxidization of tin selenide.…”

“…[ 14–16 ] In particular, sulfur‐doped metal selenide can be transformed into a heterostructure consisting of metal sulfide/metal selenide after an electrochemical reaction. [ 17–19 ] This can enhance the electrochemical properties because of the built‐in electrical fields and the alleviation of crystal growth over repeated cycles. Furthermore, doping carbon materials with sulfur is an effective strategy for improving the conductivity of carbon.…”

Recent Advances in Heterostructured Anode Materials with Multiple Anions for Advanced Alkali‐Ion Batteries

“…[64,[86][87][88][89][90] Furthermore, it has been reported that the presence of different materials during galvanostatic charge and discharge processes helps alleviate the volume change of the electrode materials because the compounds undergo electrochemical processes at different potentials; materials that are inactive at a certain potential help release the strain received by the other material, and consequently, the cycle life of the electrodes can be prolonged. [55,61,83] To understand the effects of heterointerfaces on enhancing the electrochemical properties, a combination of theoretical calculations and experimental methods is widely used, which is discussed in the section below.…”

“…For example, SnS/SnSe 2 heterostructured electrode reported by Wang et al goes through multi-step electrochemical reactions during discharge and charge process. [55] During discharge, SnSe 2 firstly goes through conversion process to yield metallic Sn as well as Li 2 Se, and SnS is decomposed at lower potential. Since nanosized Sn regions are in contact with SnS phase, flow of electrons occurs from metallic Sn to SnS, which also facilitates the electrochemical kinetics.…”