Facile synthesis of pristine FeS2 microflowers and hybrid rGO-FeS2 microsphere electrode materials for high performance symmetric capacitors

•FeS2 flower-like microspheres and rGO-FeS2 composites material was successfully synthesized by facile hydrothermal route.•The rGO-FeS2 composite electrode exhibit excellent electrochemical performances.•Improved penetration of Na2SO4 electrolyte ions into the rGO-FeS2 composite electrode was observed.•rGO-FeS2 composite electrode shows an capacity retention of 90% over 10,000 cycles at 0.3mAcm−2.