Core-Shell CuS@MoS₂ Cathodes for High-Performance Hybrid Mg-Li Ion Batteries

Abstract

With high theoretical specific capacity and favorable electrochemical properties, CuS is considered to be the ideal cathode material for hybrid Mg-Li ion batteries. However, the traditional CuS cathodes exhibit inferior rate performance and poor cycle stability, which limits the development and application of CuS. In this work, CuS@MoS2 with core–shell structure was prepared by two-step hydrothermal synthesis. When utilized for hybrid Mg-Li batteries, CuS@MoS2 displayes high special capacity and stable cycling performance. At current density of 50, 100 and 300 mAg−1, the first discharge capacity is 337.40, 276.28 and 254.58 mAhg−1 which are all higher than those of single CuS and MoS2. More importantly, the discharge capacity of core–shell CuS@MoS2 can remain 104.70 mAhg−1 at 100 mAg−1 after 50 cycles. These performance improvements are contributed to rich reaction sites and high conductivity of mixed metal sulfides. Furthermore, core–shell structure could relieve the volumetric change and remain structure stability for active materials. In conclusion, core–shell CuS@MoS2 could offer a new strategy for the design of high-performance cathode.

Constructing a Functionalized Electrocatalyst of a Transition Metal Chalcogenide on Accordion-Like MXene to Boost the Hydrogen Evolution Reaction

“…The (111) plane of MXene, 35 (002) plane of MoS 2 , and (102) plane of CuS are responsible for the 0.24, 0.305, and 0.64 nm lattice fringes, respectively. 36 These TEM images further confirm the successful preparation of MoS 2 /CuS/MXene. In Figure 2c−h, S, Cu, Mo, C, and Ti are dispersed throughout the electrocatalyst.…”

“…The high-resolution transmission electron microscopy (HRTEM) image of MoS 2 /CuS/MXene is shown in Figure b. The (111) plane of MXene, (002) plane of MoS 2 , and (102) plane of CuS are responsible for the 0.24, 0.305, and 0.64 nm lattice fringes, respectively . These TEM images further confirm the successful preparation of MoS 2 /CuS/MXene.…”

“…228.5 and 231.7 eV peaks can be indexed to the Mo 3d 5/2 and Mo 3d 3/2 of Mo 4+ , which confirms the existence of MoS 2 . , In the spectrum of Cu 2p (Figure d), 932.3 and 952.3 eV peaks are indexed to the 2p 3/2 and 2p 1/2 of Cu 2+ , respectively. The other two peaks (934.4 and 955 eV) correspond to the monovalent copper, which may be related to the reducibility of thiourea . The S 2– orbitals (2p 3/2 and 2p 1/2 ) can be found at 161.4 and 162.7 eV, respectively (Figure e) .…”

“…The other two peaks (934.4 and 955 eV) correspond to the monovalent copper, which may be related to the reducibility of thiourea. 36 The S 2− orbitals (2p 3/2 and 2p 1/2 ) can be found at 161.4 and 162.7 eV, respectively (Figure 4e). 43 In the C 1s spectrum (Figure 4f), C−C, C−O, and C�O can be represented by the peaks at 284.2, 285.6, and 288.1 eV, respectively.…”

A high-performance magnesium/lithium hybrid-ion battery using a hollow multi-layered NiS/Co3S4/carbon cathode and an all-phenyl-complex-based electrolyte

“…5,6 However, because of the strong polarization of bivalent Mg 2+ , the diffusion rate of Mg 2+ in cathode materials is sluggish. 7,8 It would be effective to develop Mg/Li hybrid-ion batteries (MLHBs) by utilizing a dendrite-free Mg anode and fast Li + transfer kinetics. 9,10…”