Assembly of SnSe Nanoparticles Confined in Graphene for Enhanced Sodium‐Ion Storage Performance

Abstract

Sodium-ion batteries (SIBs) have attracted much interest as a low-cost and environmentally benign energy storage system, but more attention is justifiably required to address the major technical issues relating to the anode materials to deliver high reversible capacity, superior rate capability, and stable cyclability. A SnSe/reduced graphene oxide (RGO) nanocomposite has been prepared by a facile ball-milling method, and its structural, morphological, and electrochemical properties have been characterized and compared with those of the bare SnSe material. Although the redox behavior of SnSe remains nearly unchanged upon the incorporation of RGO, its electrochemical performance is significantly enhanced, as reflected by a high specific capacity of 590 mA h g(-1) at 0.050 A g(-1) , a rate capability of 260 mA h g(-1) at 10 A g(-1) , and long-term stability over 120 cycles. This improvement may be attributed to the high electronic conductivity of RGO, which also serves as a matrix to buffer changes in volume and maintain the mechanical integrity of the electrode during (de)sodiation processes. In view of its excellent Na(+) storage performance, this SnSe/RGO nanocomposite has potential as an anode material for SIBs.

Readiness Level of Sodium‐Ion Battery Technology: A Materials Review

“…Addition of a third element to a binary system further complicates phases stability and equilibria, marking the appearance of amorphous phases or modified lattice parameters due to substitutional solid solubility of Sn into Ge, for example. [59] Overlapping potential profiles and CV scans have been obtained in this case, symptom of highly reversible processes. The highest stability is achieved by Sn50Ge25Sb25 composition, which guarantees 662 mAh g −1 after 50 cycles.…”

“…[36] On the anode side, instead, more than one single chemistry became appealing and worth to be investigated. Their most prominent drawback, namely the dramatic volume expansion during sodium alloying and consecutive mechanical disruption, has been tackled by proposing hybrid structures with carbon matrices [56][57][58][59] able to buffer volume changes. The insufficient interlayer spacing (≈0.34 nm) of standard commercially employed graphite for sodium intercalation, which has been demonstrated to require at least a 0.37 nm gap of a chemically expanded graphite [41] revealed indeed as the most important limitation.…”

Alloy‐Based Anode Materials toward Advanced Sodium‐Ion Batteries

“…[34] rGO was also employed to improve the electrical conductivity and structure stability of the electrodes toward enhanced sodium storage performance. [70] [71] As a result, the nanocomposite demonstrated a high initial capacity of 798 mA h g −1 and good cycling stability of 515 mA h g −1 at 0.1 A g −1 over 100 cycles (Figure 4f), which illustrated greatly improved rate and cycling performance as compared to the bare SnSe 2 .…”

The State and Challenges of Anode Materials Based on Conversion Reactions for Sodium Storage

“…Binary metal selenides (M = Sn, Sb) exhibiting the alloy‐type mechanism were prepared, and their electrochemical performance was evaluated as anodes in SIBs . The reversible capacities of the reported SnSe, SnSe 2 , and Sb 2 Se 3 compounds were generally lower than the theoretical capacity.…”

“…The reversible capacities of the reported SnSe, SnSe 2 , and Sb 2 Se 3 compounds were generally lower than the theoretical capacity. In comparison with bulk selenides, nanostructured selenides and their composites with conductive materials (e.g., nanosheets, nanoparticles, nanoplates, and nanowires) showed better rate capability and cycling stability as anodes in SIBs …”