Conversion Reaction of Copper Sulfide Based Nanohybrids for Sodium-Ion Batteries

Abstract

Intercalation-based anode materials for Na-ion batteries show relatively unfavorable electrochemical performances compared with those of Li-ion batteries because of the larger and heavier Na ion, as well as its higher electrode potential. In contrast, conversion-reaction-based anode materials have great potential for use in Na-ion batteries. In this study, copper sulfide nanodisks (CuS-NDs) were fabricated by a simple low-temperature reaction and applied as the anode materials for Na-ion batteries with acid-treated single-walled carbon nanotubes (a-SWCNTs), which act as a paperlike nanohybrid. The nanohybrids had a high reversible capacity of ca. 610 mA h g–1 and high rate capabilities at current rates from 0.1 to 3 A g–1 during the conversion reaction that reversibly forms Na2S and Cu metal. In addition, their electrochemical performances were stable and were maintained over 500 repetitive cycles; this stability arises from the unique nanohybrid structure, in which CuS-NDs are bound together by the a-SWCNT network.

Bullet‐like Cu9S5 Hollow Particles Coated with Nitrogen‐Doped Carbon for Sodium‐Ion Batteries

“…For comparison, the capacity of the Cu 9 S 5 electrode drops rapidly with cycling (Figure d,e). The cycling performance of the bullet‐like Cu 9 S 5 @NC hollow particles is also superior to that of other reported Cu x S‐based electrodes . The carbon coating layer helps to maintain the bullet structure of Cu 9 S 5 as verified by FESEM observation after long‐term cycling (Figure S18).…”

“…In the subsequent anodic scan, two peaks at about 1.58 and 2.14 V emerge, corresponding to the deintercalation of Na + ions from the Na α Cu β S γ structure . During the second cycle, the CV curve exhibits two new reduction peaks at about 1.95 and 1.55 V, which may be associated with phase transformation . The CV curves of the 2nd to 5th cycles are well overlapped, which suggests the excellent electrochemical reversibility of the electrode.…”

“…In contrast, the specific capacity of the Cu 9 S 5 electrode fades rapidly with the increase of current density. The rate capability of the Cu 9 S 5 @NC electrodes is also superior to that of the bulk Cu 9 S 5 particles (Figures S15 and S16) and most of the Cu x S‐based electrodes …”

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

“…[136] Similarly, urchin-like CoSe 2 single crystals, [137] NiSe 2 nanooctahedra, [138] and CuS 2 nanodisks [139] have also been reported. Nanostructurization and morphology engineering is one of the most relevant.…”

Pyrolytic Carbon Nanosheets for Ultrafast and Ultrastable Sodium‐Ion Storage

“…In contrast, Na‐ion batteries (NIBs) are considered among the most promising next‐generation energy storage devices because of the ubiquitous and large Na resources and chemistry similar to conventional Li‐ion batteries . NIB technologies have rapidly progressed with electrodes as the core; carbon‐based materials (CMs), metal oxide/sulfide/phosphide, and alloying compounds have been reported as potential anode materials for sodium ion storage . Among these, CMs have several advantageous features, such as sustainable and cheap precursor materials and simple fabrication processes as well as tunable materials and/or an electrochemical performance .…”