Highly Efficient Sodium‐Ion Storage Enabled by an rGO‐Wrapped FeSe₂ Composite

Abstract

Exploitation of superior anode materials is a key step to realize the pursuit of high‐performance sodium‐ion batteries. In this work, a reduced graphene oxide‐wrapped FeSe2 (FeSe2@rGO) composite derived from a metal–organic framework (MOF) was synthesized to act as the anode material of sodium‐ion batteries. The MOF‐derived carbon framework with high specific surface area could relieve the large volumetric change during cycling and ensure the structural stability of electrode materials. Besides, the rGO conductive network allowed to promote the electron transfer and accelerate reaction kinetics as well as to provide a protection role for the internal FeSe2. As a result, the FeSe2@rGO composite exhibited a high capacity of 350 mAh g−1 after 600 cycles at 5 A g−1. Moreover, in situ XRD was conducted to explore the reaction mechanism of the FeSe2@rGO composite upon sodiation/de‐sodiation. Importantly, the presented method for the synthesis of MOF‐derived materials wrapped by rGO could not only be used for FeSe2@rGO‐based sodium‐ion batteries but also for the different transition metal‐based composite materials for electrochemical devices, such as water splitting and sensors.

Yolk‐Shell Spindle‐Shaped FeSe2@N‐Doped Carbon Decorated on rGO with High‐Rate Capability and Cycling Stability in a Wide Temperature Range for Sodium Ion Batteries**

“…ChemElectroChem material, but also avoids agglomeration caused by particle fragmentation and maintains the integrity of the overall 3D structure of the material. As expected, [15,[52][53] the synergistic effect of rGO and hollow structure should be responsible for the excellent electrochemical property of the YS-FeSe 2 @NC@rGO.…”

Heterostructured SnSe2-CoSe2 microspheres embedded in reduced graphene oxides as an anode material with high sodium storage

“…Furthermore, as the high-resolution SEM image shown in Fig. 3c, the microspheres are tightly enclosed by the rGO film, which is in favor of the electron transport, preventing the pulverization the SnSe 2 -CoSe 2 microspheres and buffering the volume change during sodiation/desodiation, thereby stabilizing the structural integrity [44]. Figure 3 d presents the TEM images of the rGO/SnSe 2 -CoSe 2 .…”

RGO-Coated MOF-Derived In₂Se₃ as a High-Performance Anode for Sodium-Ion Batteries

“…However, In2Se3@C only exhibits a reversible capacity of 382 mAh•g −1 at the same current density. The obvious difference between the capacity of these two samples is caused by the synergistic effect between the rGO network and active material, which can expose more active sites and accelerate the reaction kinetics 50 . With the increase in current density, the capacity difference between the two samples is not so distinct and was almost the same at 5 A•g −1 .…”