Template‐Free Synthesis of Hierarchical Composite Nanotubes with Superior Lithium and Sodium Storage Performance

Abstract

2D transition metal disulfides are one of the most preferred materials for lithium‐/sodium‐ion batteries (LIBs). However, complex processes and structural instability during cycling are challenges faced. Herein, the hierarchical composite nanotubes CeO2@C@MoS2 (MS/CNTs) are prepared by electrostatic spinning, followed by a simple carbon coating method. The as‐prepared composite nanotubes with self‐assembled layer structures are characterized by a more stable structure compared with traditional nanofibers due to the existence of a dense skeleton. As a result of the stable framework structure, MS/CNTs exhibit excellent electrochemical performance in LIBs (1002 mA hg−1 at 0.1 A g−1 and 690 mA hg−1 at 1 A g−1 after 500 cycles) and super‐long cyclic stability and electrochemical performance (550 mA hg−1 at 2 A g−1 after 2400 cycles). MS/CNTs also show excellent storage performance in sodium batteries (440 mA hg−1 at 0.5 A g−1, 400 mA hg−1 at 1 A g−1). The stability of MoS2 nanotubes is effectively improved by chemical and physical methods, mainly due to the support of the CeO2@C, metal–organic framework (MOF) tube skeleton, which avoids the shedding of nanotubes after cycling, maintaining a unique structural topography even after 500 cycles.

Research progress on carbon materials as negative electrodes in sodium‐ and potassium‐ion batteries

“…A favorable reversible capacity of 132 mAh g −1 after 5000 cycles at 4000 mA g −1 [168] MS/CNTs 440 mAh g −1 at 0.5 A g −1 , 400 mAh g −1 at 1 A g −1 [234] NC@CoS 2 @CNTs Reversible specific capacities of 669 and 334 mAh g −1 at the current densities of 200 mA g −1 and 5000 mA g −1 , respectively, and unprecedented cycling stability of approximately 0.014% capacity decay per cycle over 1000 cycles at 3000 mA g −1 SnS@CNT Capacities of 666 and 615 mAh g −1 after 100 (100% retention) and 500 cycles (92% retention) at a current density of 1 A g −1 [239] in the carbon negative electrode. Su et al 215 developed a continuous and flexible porous carbon nanofiber membrane as a negative electrode material for SIBs by electrospinning a mixture of polyacrylonitrile and ultrafine zeolite-imidazolate skeleton (ZIF-8) nanoparticles and then carbonizing it at 1200°C (Figure 14B).…”