Reduced graphene oxide-wrapped pyrite as anode materials for Li-ion batteries with enhanced long-term performance under harsh operational environments

•A facile route to rGO wrapped cauliflower-like FeS2 microspheres has been provided.•FeS2@rGO electrodes possessed outstanding performance under harsh environments.•These attributes make FeS2@rGO particles promising candidate as anode materials.

Cauliflower-like FeS2 microspheres tightly wrapped by reduced graphene oxide (rGO-wrapped FeS2) have been synthesized by a facile and eco-friendly solution route. Self-assembled mesostructured FeS2 microspheres wrapped by rGO delivered excellent cycle performances, i.e. a remarkable reversible capacity of 1720 mAh g−1 at a current density of 0.2 A g−1 after 700 cycles at ambient temperature and an outstanding reversible capacity of 340 mAh g−1 at a current density of 5.0 A g−1 after 800 cycles as operated at an extreme temperature of 85 °C. All of these characteristics of rGO-wrapped FeS2 could be ascribed to artificially designed microstructure and gradual change of electrochemical reaction upon Li-cycling, making them promising anode materials for power batteries with ultra-long lifetimes and large energy density under harsh operational windows.

Graphical abstractCauliflower-like FeS2 microspheres tightly wrapped by reduced graphene oxide (FeS2@rGO) have been synthesized by a facile and eco-friendly solution reaction route. Self-assembled mesostructured FeS2 microspheres @rGO delivered excellent cycle stability, i.e. a remarkable reversible capacity of 1720 mAh g−1 at a current density of 0.2 A g−1 after 700 cycles at ambient temperature and an outstanding reversible capacity of 340 mAh g−1 at a current density of 5.0 A g−1 after 800 cycles as operated at an extreme temperature of 85 °C. All of these characteristics make FeS2 microspheres@rGO promising anode materials for LIBs with ultra-long lifetimes and large energy density.Download high-res image (88KB)Download full-size image