Hierarchical Hollow‐Nanocube Ni−Co Skeleton@MoO₃/MoS₂ Hybrids for Improved‐Performance Lithium‐Ion Batteries

Abstract

Improving the performance of anode materials for lithium-ion batteries (LIBs) is ah otly debated topic. Herein, hollow NiÀCo skeleton@MoS 2 /MoO 3 nanocubes (NCM-NCs), with an average size of about1 93 nm, have been synthesized through af acile hydrothermal reaction. Specifically, MoO 3 /MoS 2 composites are grown on NiÀCo skeletons derived from nickel-cobaltP russian blue analogue nanocubes (NiÀCo PBAs). The NiÀCo PBAs were synthesized through a precipitation method and utilized as self-templates that provided al arger specific surface area for the adhesion of MoO 3 /MoS 2 composites. According to Raman spectroscopy results,a s-obtained defect-richM oS 2 is confirmed to be a metallic 1T-phase MoS 2 .F urthermore, the average particle size of NiÀCo PBAs ( % 43 nm) is only about one-tenth of the previously reported particles ize ( % 400 nm). If assessed as anodes of LIBs, the hollow NCM-NC hybrids deliver an excellent rate performance and superiorc ycling performance (with an initial discharge capacity of 1526.3 mAh g À1 and up to 1720.6 mAh g À1 after 317 cycles under ac urrent density of 0.2 Ag À1 ). Meanwhile, ultralong cycling life is retained, even at high current densities (776.6 mAh g À1 at 2Ag À1 after 700 cycles and 584.8 mAh g À1 at 5Ag À1 after 800 cycles). Moreover,a tarate of 1Ag À1 ,t he average specific capacity is maintained at 661 mAh g À1 .T hus,t he hierarchical hollow NCM-NC hybridsw ith excellent electrochemical performance are ap romising anodem aterial for LIBs.[a] J.Supporting information and the ORCID identification number(s) for the author(s) of this article can be found under: https://doi.

Encapsulation of 2D MoS2 nanosheets into 1D carbon nanobelts as anodes with enhanced lithium/sodium storage properties

“…The decrease in R ct can be attributed to the process of activation after cycling. Furthermore, based on eqn (5) and (6), the diffusion coefficient of Li + ( D Li+ ) can be obtained: 66,69,70 D = R 2 T 2 /2 n 4 F 4 σ w 2 A 2 C 2 Z ′ = R + σ w ω -1/2 where R and T represent the gas constant and temperature, respectively. A , C , n , F and σ w are ascribed to the area of the electrode, the concentration of Li + , the number of electrons, Faraday constant, and Warburg coefficient, respectively.…”

Core–Sheath Structured MoO3@MoS2 Composite for High-Performance Lithium-Ion Battery Anodes

“…The main peaks located at 230.48, 232.85, 233.29, and 235.94 eV can be assigned to Mo 4+ 3d 5/2 , Mo 6+ 3d 5/2 , Mo 4+ 3d 3/2 , and Mo 6+ 3d 3/2 , respectively, with both Δ E values of Mo 4+ and Mo 6+ 3d spin–orbit splitting peaks ≈3 eV. , This result confirms the existence of both MoO 3 and MoS 2 in the composite. Besides, the S 2p has two peaks (Figure d) with BE values of 161.84 and 163.19 eV, which are attributed to S 2p 3/2 and S 2p 1/2 of S 2– . , Furthermore, the peak with a BE at 530.78 eV (Figure e) corresponds to lattice oxygen in crystalline MoO 3 , while another fitted peak located at 531.76 eV might be related to the O–H bond of surface adsorbed H 2 O. , …”

Synergistic Interface and Mesopore Engineering with More and Quicker Ion Storage for Enhanced Performance of Lithium‐Ion Battery

“…The decrease in specific capacity can be assigned to the formation of the SEI film, the decomposition of electrolyte, and the incomplete conversion of the electrochemical reactions. [36][37][38][39][40] More importantly, the ZnO/Co 3 O 4 electrode shows an excellent discharge capacity of 1,133.2 mAh g À 1 and a higher capacity retention rate of 90.5 % in the second cycle. Compared with ZnO@C and Co 3 O 4 @C electrodes, the ZnO/ Co 3 O 4 @C electrode has a long cycling life, high reversible specific capacity, and low capacity loss (see Figure S8).…”