One-pot Hydrothermal Synthesis of RGO/FeS Composite on Fe Foil for High Performance Supercapacitors

A porous RGO/FeS composite was in-situ grown on Fe foil surface. This RGO/FeS was directly used as supercapacitor electrode, which exhibited excellent electrochemical performance: 900 mF cm−2 (300Fg−1) and 97.5% maximum capacity retention after 2000 cycles. [Display omitted] •RGO/FeS in-situ grown on Fe foil via facile one-pot hydrothermal method.•Fe foil served as the iron source of FeS, reductant of GO and current collector.•A porous structure with the interconnection of FeS nanosheets.•A bind-free supercapacitor electrode with excellent performance. RGO/FeS composites on Fe foil were successfully prepared via a facile one-pot hydrothermal method, in which Fe foil acted as Fe source of FeS, reductant of GO and subsequent current collector. As-prepared RGO/FeS was directly served as the electrode of supercapacitor which exhibited a high specific capacitance of 900 mF cm−2 (300Fg−1) and a superior cyclability of 97.5% maximum capacity retention after 2000 cycles. Furthermore, an asymmetric supercapacitor (ASC) was assembled using Ni(OH)2 as the positive electrode and RGO/FeS as the negative electrode. This ASC delivered a high power density of 20930.4Wkg−1 with an energy density of 11.63 Wh kg−1, or a high energy density of 27.91 Wh kg−1 at the power density of 2093.18Wkg−1, indicating RGO/FeS is a promising negative electrode of supercapacitor.