Coated/Sandwiched rGO/CoSx Composites Derived from Metal–Organic Frameworks/GO as Advanced Anode Materials for Lithium‐Ion Batteries1. Issue 4 (8th January 2016) - Yin, Dongming
Abstract: Rational composite materials made from transition metal sulfides and reduced graphene oxide (rGO) are highly desirable for designing high‐performance lithium‐ion batteries (LIBs). Here, rGO‐coated or sandwiched CoS x composites are fabricated through facile thermal sulfurization of metal–organic framework/GO precursors. By scrupulously changing the proportion of Co 2+ and organic ligands and the solvent of the reaction system, we can tune the forms of GO as either a coating or a supporting layer. Upon testing as anode materials for LIBs, the as‐prepared CoS x ‐rGO‐CoS x and rGO@CoS x composites demonstrate brilliant electrochemical performances such as high initial specific capacities of 1248 and 1320 mA h g −1, respectively, at a current density of 100 mA g −1, and stable cycling abilities of 670 and 613 mA h g −1, respectively, after 100 charge/discharge cycles, as well as superior rate capabilities. The excellent electrical conductivity and porous structure of the CoS x /rGO composites can promote Li + transfer and mitigate internal stress during the charge/discharge process, thus significantly improving the electrochemical performance of electrode materials. Abstract : High‐performance anode materials : Composites made of reduced graphene oxide (rGO) coated or sandwiched CoS x are constructed through facile thermal sulfurization of a metal–organic framework/GO precursor, and used as high‐performance anode materials for lithium‐ion batteries (see scheme).