MoS2 nanoflowers implanted in nitrogen-doped carbon fibers with Fe2O3 nanoparticles decorated for enhanced lithium storage performance

Abstract

MoS2 has attracted extensive attention due to its unique two-dimensional layered structure and high theoretical capacity. Unfortunately, the large volume variation and sluggish lithiation kinetics during charging/discharging result in low-rate capability and poor cyclic stability. To solve those issues, MoS2/Fe2O3 @ carbon fiber (CNF) composite was designed delicately by implanting MoS2 nanoflowers in nitrogen-doped carbon fibers with Fe2O3 nanoparticles decorated. The carbon nano-fibers served as a holder to accommodate the volume expansion of MoS2 and provide a high-speed channel for electron transport, while Fe2O3 nanoparticles are apt to form heterojunction with MoS2, producing an internal electric field to enhance the ionic dynamic. As a result, the optimized sample, denoted as MoS2/Fe2O3 @CNF-3, exhibits high first discharge capacity of ∼1370 mAh g−1 at 50 mA g−1 and excellent cycle performance (559.74 mAh g−1 after 500 cycles at 1 A g−1, with capacity retention rate of 71.6%). In summary, the design techniques of heterojunction building and carbon encapsulation can be applied to different energy storage materials and have significant potential for enhancing lithium-ion battery performance electrochemically.