Bottom‐Up Synthesis of MoS<sub>2</sub>/CNTs Hollow Polyhedron with 1T/2H Hybrid Phase for Superior Potassium‐Ion Storage
Kuan Wu, Xu Cao, Minyue Li, Bo Lei, Jing Zhan, Minghong Wu
Abstract
Abstract Enslaved to the large‐size K‐ions, the construction of suitable anode materials with superior and stable potassium‐ion storage properties is a major challenge. 1T phase MoS 2 possesses higher conductivity, bigger interlayer distance, and more electrochemically active sites than the 2H phase, which offers intriguing benefits for energy‐related applications. In this work, the 1T/2H‐phase hybrid MoS 2 nanosheets are successfully anchored in the N‐doped carbon nanotube hollow polyhedron (1T/2H‐MoS 2 /NCNHP) by a bottom‐up solvothermal method. For the synthesized 1T/2H‐MoS 2 /NCNHP, the fewer‐layer 1T/2H‐MoS 2 nanosheets are embedded in an N‐doped carbon nanotube hollow polyhedron, with an enlarged interlayer spacing of 0.96 nm. When evaluated as anode material for potassium‐ion batteries, the 1T/2H‐MoS 2 /NCNHP hybrid presents outstanding potassium storage performance. It delivers a high‐specific capacity of 519.2 mAh g −1 at 50 mA g −1 and maintains 281.2 mAh g −1 at 1 A g −1 over 500 cycles. The good potassium‐ion electrochemical performance is attributed to the rational structural design and the synergistic effect of the components. Moreover, the 1T‐MoS 2 nanosheet has excellent electrical conductivity and its enlarged interlayer spacing reduces the barrier for the embedding and stripping of K ions. Finally, the practical application of the 1T/2H‐MoS 2 /NCNHP electrode material is also evaluated by assembled K‐ion full cells.