Spatially Confined Synthesis of SnSe Spheres Encapsulated in N, Se Dual-Doped Carbon Networks toward Fast and Durable Sodium Storage

Abstract

On account of the high theoretical capacity and preferable electrochemical reversibility, tin selenides have emerged as potential anode materials in the field of sodium ion batteries (SIBs). Unfortunately, the large volume changes, low electrical conductivity, and shuttling effect of polyselenides have impeded their real application. In this work, we present a spatially confined reaction approach for controllable fabrication of SnSe spheres, which are embedded in polydopamine (PDA)-derived N, Se dual-doped carbon networks (SnSe@NSC) through a one-step carbonization and selenization method. The NSC shell can not only buffer the volume changes during the cycling but also ensure strong coupling interaction between the SnSe core and carbon shell through Sn–C bonds, leading to excellent conductivity and structural integrity of the composite. Meanwhile, DFT theory calculations confirm that N, Se codoping in the carbon shell can endow the composite with enhanced adsorption energy and accelerated transfer ability of Na+. Consequently, the SnSe@NSC anode exhibits a high discharge capacity of 302.6 mA h g–1 over 500 cycles at 1 A g–1 and a competitive rate capability of 285.3 mA h g–1 at 10 A g–1. Additionally, a sodium ion full battery is assembled by coupling the SnSe@NSC anode with the cathode of Na3V2(PO4)3 and verified with good cycling durability (190 mA h g–1 at 1 A g–1 over 500 cycles) and high energy density (204.3 W h kg–1). Our scalable and facile design of heterostructured SnSe@NSC provides a new avenue to develop novel advanced anode materials for SIBs.

Self-assembled nanoflower-like FeSe2/MoSe2 heterojunction anode with enhanced kinetics for superior-performance Na-ion half/full batteries

“…3f ), the rate performance of the FMSe electrode is outstanding. [38][39][40][41][42][43][44][45][46][47] Furthermore, the long-term cycling performance of the FMSe electrode is shown in Fig. 3g, the long-term cycling stability of FMSe is further evaluated at a high current density of 5.0 A g −1 , and the capacity is maintained at 352.2 mA h g −1 even after 4200 loops.…”

Prussian Blue Analogue-Derived Fe-Doped CoS2 Nanoparticles Confined in Bayberry-like N-Doped Carbon Spheres as Anodes for Sodium-Ion Batteries

“…As shown in Figure 5 c, the CV profiles of the Fe-CoS 2 /NC-3 electrode maintained similar shapes at all scan rates, reflecting the low polarization of the electrode. As we know, the capacitive and diffusion behaviors of the electrode can be evaluated from the relationship between the peak current ( i ) and scan rate ( v ) according to the following equation [ 72 ]: …”

Surface-driven fast sodium storage enabled by Se-doped honeycomb-like macroporous carbon

“…20,21 In addition, Se-doping has been proven to be able to change the state of electron distribution and subsequently improve the electrical conductivity of target materials. [22][23][24][25] Moreover, the atomic size of Se is very large (40.2 nm in diameter), so the introduction of the Se element can effectively expand the interlayer distance of carbon to improve the diffusion kinetics of Na + . 24,26 Despite these unique application advantages, Se-doped carbons as anodes for SIBs are rarely reported.…”