Co3S4 Nanosheets on Carbon Cloth as Free-Standing Anode with Improved Pseudocapacitive Storage for High-Performance Li-Ion Batteries

Abstract

Rationally engineered anode materials with high specific capacities and rate capability are essential for lithium-ion batteries (LIBs). In this paper, a free-standing anode composed of Co3S4 nanosheets arrays and carbon cloth (abbreviated Co3S4@CC) was fabricated for high performance LIBs. The three-dimensional (3D) porous carbon cloth could not only improve the conductivity but also boost Li[Formula: see text] transfer and increase contact area for reactions. Besides, the porous thin Co3S4 nanosheets possessing strong interaction with carbon cloth by formation of C–S bond and high surface area could facilitate the mitigation of volume expansion and reduction of Li[Formula: see text] diffusion distance, coupling with efficient contact with electrolytes during cycling process. As expected, the freestanding Co3S4@CC anode presents pseudocapacitance-dominated storage behavior with a very high specific capacity of 847[Formula: see text]mAh g[Formula: see text] at 250[Formula: see text]mA g[Formula: see text] after 100 cycles and good rate capability for LIBs. This work provides an approach for designing metal sulfides with high capacities and rate capability for LIBs, especially flexible LIBs.