Ultra-Thin ReS Nanosheets Grown on Carbon Black for Advanced Lithium-Ion Battery Anodes.

ReS nanosheets are grown on the surface of carbon black (CB) via an efficient hydrothermal method. We confirmed the ultra-thin ReS nanosheets with ≈1-4 layers on the surface of the CB (ReS@CB) by using analytical techniques of field emission scanning electron microscopy (FESEM) and high-resolution transmission electron microscopy (HRTEM). The ReS@CB nanocomposite showed high specific capacities of 760, 667, 600, 525, and 473 mAh/g at the current densities of 0.1 (0.23 C), 0.2 (0.46 C), 0.3 (0.7 C), 0.5 (1.15 C) and 1.0 A/g (2.3 C), respectively, in conjunction with its excellent cycling performance (432 mAh/g at 2.3 C; 91.4% capacity retention) after 100 cycles. Such LIB performance is greatly higher than pure CB and ReS powder samples. These results could be due to the following reasons: (1) the low-cost CB serves as a supporter enabling the formation of ≈1-4 layered nanosheets of ReS, thus avoiding its agglomeration; (2) the CB enhances the electrical conductivity of the ReS@CB nanocomposite; (3) the ultra-thin (1-4 layers) ReS nanosheets with imperfect structure can function as increasing the number of active sites for reaction of Li ions with electrolytes. The outstanding performance and unique structural characteristics of the ReS@CB anodes make them promising candidates for the ever-increasing development of advanced LIBs.