Cuprous Self-Doping Regulated Mesoporous CuS Nanotube Cathode Materials for Rechargeable Magnesium Batteries

Abstract

Copper sulfides are broadly explored as the possible cathode materials for rechargeable magnesium batteries on account of their high theoretical capacity of 560 mAh g–1. However, the CuS cathodes usually suffer from serious capacity decay caused by structure collapse during the repeated magnesiation/demagnesiation process. Herein, we present a cuprous self-doping strategy to synthesize mesoporous CuS nanotubes with robust structural stability for rechargeable magnesium batteries and regulate their electrochemical magnesium storage behavior. Electrochemical results show that the mesoporous CuS nanotubes can exhibit high specific capacity, remarkable cycling performance, and good rate capability. The observed discharge capacity of the mesoporous CuS nanotubes could reach about 281.2 mAh g–1 at 20 mA g–1 and 168.9 mAh g–1 at 500 mA g–1. Furthermore, a remarkable ultralong-term cyclic stability with a reversible capacity of 72.5 mAh g–1 at 1 A g–1 is obtained after 550 cycles. These results demonstrate that the mesoporous nanotube structure and the simple cuprous self-doping effect could promote the practical application of copper sulfide cathode materials for rechargeable magnesium batteries.

Designing Nanostructured Metal Chalcogenides as Cathode Materials for Rechargeable Magnesium Batteries

“…[38,39,103] The positive impact of nanosizing on their performance as cathodes for RMBs have also been demonstrated in recent studies. In the group of conversion cathodes, nanostructured CuS cathodes (e.g., nanosheets, [34] nanoflakeassembled nanocages, [55] nanotubes [56] ) are the most promising with their high theoretical capacity, cost efficiency, and capability of cycling at room temperature. For these materials, nanostructuring has been beneficial in mitigating the drastic morphological and volume changes during conversion reactions, and the capability of cycling at high current density as shown in Figure 9.…”

“…[53] In addition, the conversion cathode exhibits large voltage hysteresis observed between discharge and charge, which results in low energy efficiency. [53,54] The metal chalcogenides that have been experimentally attempted as conversion cathode for Mg batteries are CuS, [14,17,18,[23][24][25][26]34,[55][56][57][58] Ag 2 S and Ag 2 Se, [15,19,59] NiCo 2 Se 4 , [28] Cu 2−x Se, [13] CuSe, [60] Ni 0.85 Se, [61] CuS 1−x Se x , [16] CoS, [62] FeS 2, [63] Sb 2 Se 3 , [20] Bi 2 Se 3 , [20] CoSe 2 , [21] and Ni 0.75 Fe 0.25 Se 2.…”

Encapsulating Metal-Organic-Framework Derived Nanocages into a Microcapsule for Shuttle Effect-Suppressive Lithium-Sulfur Batteries

“…Stable performance indicates that microcapsules can be used in different conditions, which are significant for practical applications. Figure 9a displays CV curves of Co3O4/S-infilled microcapsules at 0.6 to 1 mV s −1 ; Figure 9b displays a logarithmic relationship according to i = av b , where i and v stand for the peak current and rate, respectively [49]. The b value of 0.5 represents a diffusive-controlled process, and b = 1 indicates a capacitive behavior.…”

Synthesis and Applications of Nanostructured Hollow Transition Metal Chalcogenides

“…MIBs [192] Fe 7 S 8 /C@d-MoS 2 Hollow nanocages 505 mAh g −1 at 0.5 A g −1 , 318 mAh g −1 at 5 A g −1 286 mAh g −1 at 4 A g −1 , 500 cycles PIBs [127] SnS 2 @C Hollow nanobox 508 mAh g −1 at 0.1 A g −1 , 222 mAh g −1 at 2 A g −1 347 mAh g −1 at 1 A g −1 , 300 cycles 72% capacity retention PIBs [134] N-CoS 2 Yolk-shell nanospheres 744 mAh gZn −1 at 5 mA cm −2 165 h at 10 mA cm −2 ZABs [193] NiCo 2 S 4 Hollow spheres 1387.4 F g −1 at 1 A g −1 , 755 F g −1 at 10 A g −1 1387.5 F g −1 at 1 A g −1 , 4500 cycles 92.2% capacity retention SCs [194] For example, a semiconductor photocatalyst condenses electrons on the catalyst surface, thereby improving the photocatalytic CO 2 reduction ability. [69] Therefore, the preparation of some new-type, good-effect, and environment friendly photocatalysts has aroused great interest from many researchers.…”

“…In terms of electrochemical energy storage system, in addition to LIBs [190] and SIBs, [191] rechargeable batteries also include magnesium ion batteries (MIBs), [192] potassium ion batteries (PIBs), [127,134] and Zn-air batteries (ZABs), [193] etc. Among them, supercapacitors (SCs) and batteries are used as energy storage components and are part of the energy storage system.…”